Project Report
Presented to
Prof. Ausif Mahmood
Implementation of complex
inter-networking
By
Mohammad
Kashif Saleem
SID
0428128
Enhanced Interior
Gateway Routing Protocol
In this project complex network for a
small enterprise is designed and implemented using six 2500 series Cisco
routers. Two Autonomous Systems AS65000 and AS65500 are created and Border
Gateway protocol BGP is configured with various attributes for their
communication. For AS65000 Open Shortest Path First, OSPF is configured as
interior gateway Protocol. For AS65500 Routing Information Protocol V2, RIP2
and Enhanced IGRP are configured as IGPs. Route redistribution is implemented
across Autonomous Systems and scalability issues are dealt acutely.
Large internetworks spanning multiple
workgroups, sub networks, and host computers create special problems for system
administrators. Like managers of local networks, they must deal with products
from multiple vendors, get different network operating systems to communicate,
and justify the costs of new services and applications.
But they also face the task of selecting, managing, and maintaining
bridges, routers, and gateways - the internetworking devices that permit widely
separated clusters of networks to communicate. These products offer important
capabilities to help network managers solve particular problems, but each poses
special implementation challenges, too.
This is especially true of routers and their associated routing
protocols. Routers, connect logically separate networks operating under the
same transport protocol, such as the Transmission Control
Protocol/Internet Protocol (TCP/IP)
Routers, which operate at the network (or third) layer of the Open
Systems Interconnection (OSI) reference model, are
protocol-dependent devices. That is, they must support each routing protocol on
that LAN.
Routing protocols can be broadly categorized as:
a) Interior
Gateway Protocols
b)
Exterior Gateway Protocols
Interior
Gateway Protocols
An IGP (Interior Gateway Protocol) is a protocol
for exchanging routing information between gateways (hosts with routers) within
an autonomous network (for example, a system of corporate local area networks).
The routing information can then be used by the Internet Protocol or other
network protocols to specify how to route transmissions.
Three IGPs used in this project are:
a) Open
Shortest Path First. (OSPF)
b) Routing
Information Protocol-Version 2. (RIP2)
c)
Enhanced Interior Gateway Routing Protocol.
(EIGRP)
Exterior
Gateway Protocol
Exterior Gateway Protocol (EGP) is a protocol or exchanging
routing information between two neighbor gateway hosts (each with its own
router) in a network of autonomous systems. EGP is commonly used between hosts
on the Internet to exchange routing table information. The routing table
contains a list of known routers, the addresses they can reach, and a cost
metric associated with the path to each router so that the best available route
is chosen. Each router polls its neighbor at intervals between 120 to 480
seconds and the neighbor responds by sending its complete routing table. EGP-2
is the latest version of EGP.
A more recent exterior gateway protocol, the Border Gateway
Protocol (BGP), provides additional capabilities.
Open Shortest Path First
Routing Hierarchy
Unlike RIP, OSPF can operate
within a hierarchy. The largest entity within the hierarchy is the autonomous
system (AS), which is a collection of networks under a common administration
that share a common routing strategy. OSPF is an intra-AS (interior gateway)
routing protocol, although it is capable of receiving routes from and sending
routes to other ASs.
An AS can be divided into a number
of areas, which are groups of contiguous networks and attached hosts. Routers
with multiple interfaces can participate in multiple areas. These routers,
which are called Area Border Routers, maintain separate topological databases
for each area.
A topological database is
essentially an overall picture of networks in relationship to routers. The
topological database contains the collection of LSAs received from all routers
in the same area. Because routers within the same area share the same
information, they have identical topological databases.
The term domain sometimes
is used to describe a portion of the network in which all routers have identical
topological databases. Domain is frequently used interchangeably with AS.
An area's topology is invisible to
entities outside the area. By keeping area topologies separate, OSPF passes
less routing traffic than it would if the AS were not partitioned.
Area partitioning creates two
different types of OSPF routing, depending on whether the source and the
destination are in the same or different areas. Intra-area routing occurs when
the source and destination are in the same area; inter area routing occurs when
they are in different areas.
An OSPF backbone is responsible
for distributing routing information between areas. It consists of all Area
Border Routers, networks not wholly contained in any area, and their attached
routers.
The backbone itself is an OSPF
area, so all backbone routers use the same procedures and algorithms to
maintain routing information within the backbone that any area router would.
The backbone topology is invisible to all intra-area routers, as are individual
area topologies to the backbone.
Areas can be defined in such a way
that the backbone is not contiguous. In this case, backbone connectivity must
be restored through virtual links. Virtual links are configured between any
backbone routers that share a link to a nonbackbone area and function as if
they were direct links.
AS border routers running OSPF
learn about exterior routes through exterior gateway protocols (EGPs), such as
Exterior Gateway Protocol (EGP) or Border Gateway Protocol (BGP), or through
configuration information
SPF Algorithm
The Shortest Path First (SPF)
routing algorithm is the basis for OSPF operations. When an SPF router is
powered up, it initializes its routing-protocol data structures and then waits
for indications from lower-layer protocols that its interfaces are functional.
After a router is assured that its
interfaces are functioning, it uses the OSPF Hello protocol to acquire
neighbors, which are routers with interfaces to a common network. The router
sends hello packets to its neighbors and receives their hello packets. In
addition to helping acquire neighbors, hello packets also act as keepalives to
let routers know that other routers are still functional.
On multi-access networks (networks
supporting more than two routers), the Hello protocol elects a designated
router and a backup designated router. Among other things, the designated
router is responsible for generating LSAs for the entire multi-access network.
Designated routers allow a reduction in network traffic and in the size of the
topological database.
When the link-state databases of
two neighboring routers are synchronized, the routers are said to be adjacent.
On multi-access networks, the designated router determines which routers should
become adjacent. Topological databases are synchronized between pairs of
adjacent routers. Adjacencies control the distribution of routing-protocol
packets, which are sent and received only on adjacencies.
Each router periodically sends an
LSA to provide information on a router's adjacencies or to inform others when a
router's state changes. By comparing established adjacencies to link states,
failed routers can be detected quickly, and the network's topology can be
altered appropriately. From the topological database generated from LSAs, each
router calculates a shortest-path tree, with itself as root. The shortest-path
tree, in turn, yields a routing table.
Packet Format
All OSPF packets begin with a 24-byte header, as illustrated
in Figure
OSPF Packets Consist of Nine Fields
The following descriptions
summarize the header fields illustrated in Figure.
Version number—Identifies
the OSPF version used.
- Type—Identifies
the OSPF packet type as one of the following:
o
Hello—Establishes and maintains
neighbor relationships.
- Database
description—Describes the contents of the topological
database. These messages are exchanged when an adjacency is initialized.
- Link-state
request—Requests pieces of the topological database
from neighbor routers. These messages are exchanged after a router
discovers (by examining database-description packets) that parts of its
topological database are outdated.
- Link-state
update—Responds to a link-state request packet. These
messages also are used for the regular dispersal of LSAs. Several LSAs
can be included within a single link-state update packet.
- Link-state
acknowledgment—Acknowledges link-state update packets.
- Packet
length—Specifies the packet length, including the OSPF
header, in bytes.
- Router
ID—Identifies the source of the packet.
- Area
ID—Identifies the area to which the packet belongs. All
OSPF packets are associated with a single area.
- Checksum—Checks
the entire packet contents for any damage suffered in transit.
- Authentication
type—Contains the authentication type. All OSPF protocol
exchanges are authenticated. The authentication type is configurable on
per-area basis.
- Authentication—Contains
authentication information.
- Data—Contains
encapsulated upper-layer information.
OSPF Cost
The cost (also called metric) of
an interface in OSPF is an indication of the overhead required to send packets
across a certain interface. The cost of an interface is inversely proportional
to the bandwidth of that interface. A higher bandwidth indicates a lower cost.
There is more overhead (higher cost) and time delays involved in crossing a 56k
serial line than crossing a 10M Ethernet line. The formula used to calculate
the cost is:
Cost= 10000
0000/bandwith in bps
For example, it will cost 10 EXP8/10 EXP7 = 10 to cross a
10M Ethernet line and will cost
10 EXP8/1544000 =
64 to cross a T1 line.
By default, the cost of an
interface is calculated based on the bandwidth; you can force the cost of an
interface by using the ip ospf cost <value> interface
sub-command.
Areas and Border Routers
As previously mentioned, OSPF uses
flooding to exchange link-state updates between routers. Any change in routing
information is flooded to all routers in the network. Areas are introduced to
put a boundary on the explosion of link-state updates. Flooding and calculation
of the Dijkstra algorithm on a router is limited to changes within an area. All
routers within an area have the exact link-state database. Routers that belong
to multiple areas, and connect these areas to the backbone area are called area
border routers (ABR). ABRs must therefore maintain information describing the
backbone areas and other attached areas.
An
area is interface specific. A router that has all of its interfaces within the
same area is called an internal router (IR). A router that has interfaces in
multiple areas is called an area border router (ABR). Routers that act as
gateways (redistribution) between OSPF and other routing protocols (IGRP,
EIGRP, IS-IS, RIP, BGP, Static) or other instances of the OSPF routing process
are called autonomous system border routers (ASBR). Any router can be an ABR or
an ASBR.
The Backbone and Area 0
OSPF has special restrictions when
multiple areas are involved. If more than one area is configured, one of these
areas has be to be area 0. This is called the backbone. When designing networks
it is good practice to start with area 0 and then expand into other areas later
on.
The backbone has to be at the
center of all other areas, i.e. all areas have to be physically connected to
the backbone. The reasoning behind this is that OSPF expects all areas to
inject routing information into the backbone and in turn the backbone will
disseminate that information into other areas.
Neighbors
Routers that share a common
segment become neighbors on that segment. Neighbors are elected via the Hello
protocol. Hello packets are sent periodically out of each interface using IP
multicast (Appendix B). Routers become neighbors as soon as they see themselves
listed in the neighbor's Hello packet. This way, a two-way communication is
guaranteed. Neighbor negotiation applies to the primary address only.
Secondary addresses can be configured on an interface with a restriction that
they have to belong to the same area as the primary address.
Two routers will not become
neighbors unless they agree on the following:
- Area-id: Two
routers having a common segment; their interfaces have to belong to the
same area on that segment. Of course, the interfaces should belong to the
same subnet and have a similar mask.
- Authentication: OSPF
allows for the configuration of a password for a specific area. Routers
that want to become neighbors have to exchange the same password on a
particular segment.
- Hello and Dead
Intervals: OSPF exchanges Hello packets on each segment.
This is a form of keep alive used by routers in order to acknowledge their
existence on a segment and in order to elect a designated router (DR) on
multi-access segments. The Hello interval specifies the length of time, in
seconds, between the hello packets that a router sends on an OSPF
interface. The dead interval is the number of seconds that a router's
Hello packets have not been seen before its neighbors declare the OSPF
router down. OSPF requires these intervals to be exactly the same between
two neighbors. If any of these intervals are different, these routers will
not become neighbors on a particular segment. The router interface
commands used to set these timers are: ip ospf hello-interval seconds
and ip ospf dead-interval seconds.
- Stub area flag: Two
routers have to also agree on the stub area flag in the Hello packets in
order to become neighbors. Stub areas will be discussed in a later
section. Keep in mind for now that defining stub areas will affect the
neighbor election process.
Adjacencies
Adjacency is the next step after
the neighboring process. Adjacent routers are routers that go beyond the simple
Hello exchange and proceed into the database exchange process. In order to minimize
the amount of information exchange on a particular segment, OSPF elects one
router to be a designated router (DR), and one router to be a backup designated
router (BDR), on each multi-access segment. The BDR is elected as a backup
mechanism in case the DR goes down. The idea behind this is that routers have a
central point of contact for information exchange. Instead of each router
exchanging updates with every other router on the segment, every router
exchanges information with the DR and BDR. The DR and BDR relay the information
to everybody else. In mathematical terms, this cuts the information exchange
from O(n*n) to O(n) where n is the number of routers on a multi-access segment.
DR Election
DR and BDR election is done via
the Hello protocol. Hello packets are exchanged via IP multicast packets
(Appendix B) on each segment. The router with the highest OSPF priority on a
segment will become the DR for that segment. The same process is repeated for
the BDR. In case of a tie, the router with the highest RID will win. The
default for the interface OSPF priority is one. Remember that the DR and BDR
concepts are per multi-access segment. Setting the ospf priority on an
interface is done using the ip ospf priority <value>
interface command. A priority value of zero indicates an interface that is not
to be elected as DR or BDR. The state of the interface with priority zero will
be DROTHER.
Adjacencies on Point-to-Point Interfaces
OSPF will always form an adjacency
with the neighbor on the other side of a point-to-point interface such as
point-to-point serial lines. There is no concept of DR or BDR. The state of the
serial interfaces is point to point.
Adjacencies on Non-Broadcast Multi-Access (NBMA) Networks
Special care should be taken when
configuring OSPF over multi-access non-broadcast medias such as Frame Relay,
X.25, and ATM. The protocol considers these media like any other broadcast
media such as Ethernet. NBMA clouds are usually built in a hub and spoke
topology. PVCs or SVCs are laid out in a partial mesh and the physical topology
does not provide the multi access that OSPF believes is out there. The
selection of the DR becomes an issue because the DR and BDR need to have full
physical connectivity with all routers that exist on the cloud. Also, because
of the lack of broadcast capabilities, the DR and BDR need to have a static
list of all other routers attached to the cloud. This is achieved using the neighbor
ip-address [priority number] [poll-interval seconds]
command, where the "ip-address" and "priority" are the IP
address and the OSPF priority given to the neighbor. A neighbor with priority 0
is considered ineligible for DR election. The "poll-interval" is the
amount of time an NBMA interface waits before polling (sending a Hello) to a
presumably dead neighbor. The neighbor command applies to routers with a
potential of being DRs or BDRs (interface priority not equal to 0).
Routing Updates
RIP sends routing-update messages
at regular intervals and when the network topology changes. When a router
receives a routing update that includes changes to an entry, it updates its
routing table to reflect the new route. The metric value for the path is
increased by 1, and the sender is indicated as the next hop. RIP routers
maintain only the best route (the route with the lowest metric value) to a
destination. After updating its routing table, the router immediately begins
transmitting routing updates to inform other network routers of the change.
These updates are sent independently of the regularly scheduled updates that
RIP routers send.
RIP Routing Metric
RIP uses a single routing metric
(hop count) to measure the distance between the source and a destination
network. Each hop in a path from source to destination is assigned a hop count
value, which is typically 1. When a router receives a routing update that
contains a new or changed destination network entry, the router adds 1 to the
metric value indicated in the update and enters the network in the routing
table. The IP address of the sender is used as the next hop.
RIP Stability Features
RIP prevents routing loops from
continuing indefinitely by implementing a limit on the number of hops allowed
in a path from the source to a destination. The maximum number of hops in a
path is 15. If a router receives a routing update that contains a new or
changed entry, and if increasing the metric value by 1 causes the metric to be
infinity (that is, 16), the network destination is considered unreachable. The
downside of this stability feature is that it limits the maximum diameter of a
RIP network to less than 16 hops. RIP includes a number of other stability
features that are common to many routing protocols. These features are designed
to provide stability despite potentially rapid changes in a network's topology.
For example, RIP implements the split horizon and hold-down mechanisms to
prevent incorrect routing information from being propagated.
RIP Timers
RIP uses numerous timers to
regulate its performance. These include a routing-update timer, a route-timeout
timer, and a route-flush timer. The routing-update timer clocks the interval
between periodic routing updates. Generally, it is set to 30 seconds, with a
small random amount of time added whenever the timer is reset. This is done to
help prevent congestion, which could result from all routers simultaneously
attempting to update their neighbors. Each routing table entry has a
route-timeout timer associated with it. When the route-timeout timer expires,
the route is marked invalid but is retained in the table until the route-flush
timer expires.
RIP 2 Packet Format
The RIP 2 specification (described in RFC 1723) allows more
information to be included in RIP packets and provides a simple authentication
mechanism that is not supported by RIP. Figure shows the IP RIP 2 packet
format.
Figure: An IP RIP 2 Packet Consists of Fields Similar
to Those of an IP RIP Packet
The following descriptions summarize the IP RIP 2 packet
format fields illustrated in Figure
Command—Indicates whether the packet is a request or a response. The request asks that a router send all or a part of its routing table. The response can be an unsolicited regular routing update or a reply to a request. Responses contain routing table entries. Multiple RIP packets are used to convey information from large routing tables.
- Version—Specifies the RIP version used. In a RIP packet
implementing any of the RIP 2 fields or using authentication, this value is
set to 2.
- Unused—Has a value set to zero.
- Address-family identifier (AFI)—Specifies the address family used. RIPv2's AFI field
functions identically to RFC 1058 RIP's AFI field, with one exception: If the
AFI for the first entry in the message is 0xFFFF, the remainder of the entry
contains authentication information. Currently, the only authentication type
is simple password.
- Route tag—Provides a method for distinguishing between internal
routes (learned by RIP) and external routes (learned from other
protocols).
- IP address—Specifies the IP address for the entry.
- Subnet mask—Contains the subnet mask for the entry. If this field is
zero, no subnet mask has been specified for the entry.
- Next hop—Indicates the IP address of the next hop to which
packets for the entry should be forwarded.
- Metric—Indicates how many internetwork hops (routers) have been
traversed in the trip to the destination. This value is between 1 and 15 for a
valid route, or 16 for an unreachable route.
Enhanced Interior Gateway Routing Protocol
The Enhanced Interior Gateway Routing Protocol (EIGRP)
represents an evolution from its predecessor IGRP. This evolution resulted from
changes in networking and the demands of diverse, large-scale internetworks.
Enhanced IGRP integrates the capabilities of link-state protocols into distance
vector protocols. Additionally, EIGRP contains several important protocols that
greatly increase its operational efficiency relative to other routing protocols.
One of these protocols is the Diffusing update
algorithm (DUAL). DUAL enables EIGRP routers
to determine whether a path advertised by a neighbor is looped or loop-free, and
allows a router running EIGRP to find alternate paths without waiting on updates
from other routers.
Enhanced IGRP provides compatibility and seamless
interoperation with IGRP routers. An automatic-redistribution mechanism allows
IGRP routes to be imported into Enhanced IGRP, and vice versa, so it is possible
to add Enhanced IGRP gradually into an existing IGRP network. Because the
metrics for both protocols are directly translatable, they are as easily
comparable as if they were routes that originated in their own autonomous
systems (ASs). In addition, Enhanced IGRP treats IGRP routes as external routes
and provides a way for the network administrator to customize them.
This chapter provides an overview of the basic operations
and protocol characteristics of Enhanced IGRP.
Enhanced IGRP Capabilities and Attributes
Key capabilities that distinguish Enhanced IGRP from other
routing protocols include fast convergence, support for variable-length subnet
mask, support for partial updates, and support for multiple network layer
protocols.
A router running Enhanced IGRP stores all its neighbors'
routing tables so that it can quickly adapt to alternate routes. If no
appropriate route exists, Enhanced IGRP queries its neighbors to discover an
alternate route. These queries propagate until an alternate route is found.
Its support for variable-length subnet masks permits routes
to be automatically summarized on a network number boundary. In addition,
Enhanced IGRP can be configured to summarize on any bit boundary at any
interface.
Enhanced IGRP does not make periodic updates. Instead, it
sends partial updates only when the metric for a route changes. Propagation of
partial updates is automatically bounded so that only those routers that need
the information are updated. As a result of these two capabilities, Enhanced
IGRP consumes significantly less bandwidth than IGRP.
Enhanced IGRP includes support for AppleTalk, IP, and
Novell NetWare. The AppleTalk implementation redistributes routes learned from
the Routing Table Maintenance Protocol (RTMP). The IP implementation
redistributes routes learned from OSPF, Routing Information Protocol (RIP),
Intermediate System-to-Intermediate System (IS-IS), Exterior Gateway Protocol
(EGP), or Border Gateway Protocol (BGP). The Novell implementation redistributes
routes learned from Novell RIP or Service Advertisement Protocol (SAP).
Underlying Processes and Technologies
To provide superior routing performance, Enhanced IGRP
employs four key technologies that combine to differentiate it from other
routing technologies: neighbor discovery/recovery, reliable transport protocol
(RTP), DUAL finite-state machine, and protocol-dependent modules.
The neighbor
discovery/recovery mechanism enables routers to dynamically learn about
other routers on their directly attached networks. Routers also must discover
when their neighbors become unreachable or inoperative. This process is achieved
with low overhead by periodically sending small hello packets. As long as a
router receives hello packets from a neighboring router, it assumes that the
neighbor is functioning, and the two can exchange routing information.
Reliable Transport Protocol (RTP) is responsible for
guaranteed, ordered delivery of Enhanced IGRP packets to all neighbors. It
supports intermixed transmission of multicast or unicast packets. For
efficiency, only certain Enhanced IGRP packets are transmitted reliably. On a
multi-access network that has multicast capabilities, such as Ethernet, it is
not necessary to send hello packets reliably to all neighbors individually. For
that reason, Enhanced IGRP sends a single multicast hello packet containing an
indicator that informs the receivers that the packet need not be acknowledged.
Other types of packets, such as updates, indicate in the packet that
acknowledgment is required. RTP contains a provision for sending multicast
packets quickly when unacknowledged packets are pending, which helps ensure that
convergence time remains low in the presence of varying speed links.
The DUAL finite-state machine
embodies the decision process for all route computations by tracking all routes
advertised by all neighbors. DUAL uses distance information to select efficient,
loop-free paths and selects routes for insertion in a routing table based on
feasible successors. A feasible successor is a
neighboring router used for packet forwarding that is a least-cost path to a
destination that is guaranteed not to be part of a routing loop. When a neighbor
changes a metric, or when a topology change occurs, DUAL tests for feasible
successors. If one is found, DUAL uses it to avoid recomputing the route
unnecessarily. When no feasible successors exist but neighbors still advertise
the destination, a recomputation (also known as a diffusing computation) must
occur to determine a new successor. Although recomputation is not
processor-intensive, it does affect convergence time, so it is advantageous to
avoid unnecessary recomputations.
Protocol-dependent modules are responsible for network
layer protocol-specific requirements. The IP-Enhanced IGRP module, for example,
is responsible for sending and receiving Enhanced IGRP packets that are
encapsulated in IP. Likewise, IP-Enhanced IGRP is also responsible for parsing
Enhanced IGRP packets and informing DUAL of the new information that has been
received. IP-Enhanced IGRP asks DUAL to make routing decisions, the results of
which are stored in the IP routing table. IP-Enhanced IGRP is responsible for
redistributing routes learned by other IP routing protocols.
Routing Concepts
Enhanced IGRP relies on four fundamental concepts: neighbor
tables, topology tables, route states, and route tagging. Each of these is
summarized in the discussions that follow.
Neighbor Tables
When a router discovers a new neighbor, it records the
neighbor's address and interface as an entry in the neighbor table. One neighbor table exists for each
protocol-dependent module. When a neighbor sends a hello packet, it advertises a
hold time, which is the amount of time that a router treats a neighbor as
reachable and operational. If a hello packet is not received within the hold
time, the hold time expires and DUAL is informed of the topology change.
The neighbor-table entry also includes information required
by RTP. Sequence numbers are employed to match acknowledgments with data
packets, and the last sequence number received from the neighbor is recorded so
that out-of-order packets can be detected. A transmission list is used to queue
packets for possible retransmission on a per-neighbor basis. Round-trip timers
are kept in the neighbor-table entry to estimate an optimal retransmission
interval.
\
Topology Tables
The topology table contains
all destinations advertised by neighboring routers. The protocol-dependent
modules populate the table, and the table is acted on by the DUAL finite-state
machine. Each entry in the topology table includes the destination address and a
list of neighbors that have advertised the destination. For each neighbor, the
entry records the advertised metric, which the neighbor stores in its routing
table. An important rule that distance vector protocols must follow is that if
the neighbor advertises this destination, it must use the route to forward
packets.
The metric that the router uses to reach the destination is
also associated with the destination. The metric that the router uses in the
routing table, and to advertise to other routers, is the sum of the
best-advertised metric from all neighbors and the link cost to the best
neighbor.
Route States
A topology-table entry for a destination can exist in one
of two states: active or passive. A destination is in the passive state when the router is not performing a
recomputation; it is in the active state when the
router is performing a recomputation. If feasible successors are always
available, a destination never has to go into the active state, thereby avoiding
a recomputation.
A recomputation occurs when a destination has no feasible
successors. The router initiates the recomputation by sending a query packet to
each of its neighboring routers. The neighboring router can send a reply packet,
indicating that it has a feasible successor for the destination, or it can send
a query packet, indicating that it is participating in the recomputation. While
a destination is in the active state, a router cannot change the destination's
routing-table information. After the router has received a reply from each
neighboring router, the topology-table entry for the destination returns to the
passive state, and the router can select a successor.
Route Tagging
Enhanced IGRP supports internal and external routes.
Internal routes originate within
an Enhanced IGRP AS.
Therefore, a directly attached network that is configured to run Enhanced IGRP
is considered an internal route and is propagated with this information
throughout the Enhanced IGRP AS. External routes are learned by another routing
protocol or reside in the routing table as static routes. These routes are
tagged individually with the identity of their origin.
External routes are tagged with the following information:
·
Router ID of the Enhanced IGRP router that redistributed
the route
- AS number of the destination
- Configurable administrator tag
- ID of the external protocol
- Metric from the external protocol
- Bit flags for default routing
Route tagging allows the network administrator to customize
routing and maintain flexible policy controls. Route tagging is particularly
useful in transit ASs, where Enhanced IGRP typically interacts with an
interdomain routing protocol that implements more global policies, resulting in
a very scalable, policy-based routing.
Enhanced IGRP Packet Types
Enhanced IGRP uses the following packet types: hello and
acknowledgment, update, and query and reply.
Hello packets are multicast for neighbor discovery/recovery and
do not require acknowledgment.
An acknowledgment packet is a
hello packet that has no data. Acknowledgment packets contain a nonzero
acknowledgment number and always are
sent by using a
unicast address.
Update packets are used to convey reachability of destinations.
When a new neighbor is discovered, unicast update packets are sent so that the
neighbor can build up its topology table. In other cases, such as a link-cost
change, updates are multicast. Updates always are transmitted reliably.
Query and reply packets are sent when a destination has no
feasible successors. Query packets are always
multicast. Reply packets are sent in response to query packets to instruct the
originator not to recompute the route because feasible successors exist. Reply packets are unicast to the originator of the
query. Both query and reply packets are transmitted reliably.
Introduction
The Border Gateway Protocol
(BGP) is an interautonomous system routing protocol. An autonomous system
is a network or group of networks under a common administration and with common
routing policies. BGP is used to exchange routing information for the Internet
and is the protocol used between Internet service providers (ISP). Customer
networks, such as universities and corporations, usually employ an Interior
Gateway Protocol (IGP) such as RIP or OSPF for the exchange of routing
information within their networks. Customers connect to ISPs, and ISPs use BGP
to exchange customer and ISP routes. When BGP is used between autonomous systems
(AS), the protocol is referred to as External BGP (EBGP). If a service provider
is using BGP to exchange routes within an AS, then the protocol is referred to
as Interior BGP (IBGP).
BGP is a very robust and scalable routing protocol, as
evidenced by the fact that BGP is the routing protocol employed on the Internet.
The Internet BGP routing tables number more than 90,000 routes. To achieve
scalability at this level, BGP uses many route parameters, called attributes, to
define routing policies and maintain a stable routing environment.
In addition to BGP attributes, classless interdomain
routing (CIDR) is used by BGP to reduce the size of the Internet routing tables.
For example, assume that an ISP owns the IP address block 195.10.x.x from the
traditional Class C address space. This block consists of 256 Class C address
blocks, 195.10.0.x through 195.10.255.x. Assume that the ISP assigns a Class C
block to each of its customers. Without CIDR, the ISP would advertise 256 Class
C address blocks to its BGP peers. With CIDR, BGP can supernet the address space
and advertise one block, 195.10.x.x. This block is the same size as a
traditional Class B address block. The class distinctions are rendered obsolete
by CIDR, allowing a significant reduction in the BGP routing tables.
BGP neighbors exchange full routing information when the
TCP connection between neighbors is first established. When changes to the
routing table are detected, the BGP routers send to their neighbors only those
routes that have changed. BGP routers do not send periodic routing updates, and
BGP routing updates advertise only the optimal path to a destination
network.
BGP Attributes
Routes learned via BGP have associated properties that are
used to determine the best route to a destination when multiple paths exist to a
particular destination. These properties are referred to as BGP attributes, and
an understanding of how BGP attributes influence route selection is required for
the design of robust networks. This section describes the attributes that BGP
uses in the route selection process:
·
Weight
- Local preference
- Multi-exit discriminator
- Origin
- AS_path
- Next hop
- Community
Weight Attribute
Weight is a Cisco-defined attribute that is local to a router.
The weight attribute is not advertised to neighboring routers. If the router
learns about more than one route to the same destination, the route with the
highest weight will be preferred.
Local Preference Attribute
The local preference
attribute is used to prefer an exit point from the local autonomous system (AS).
Unlike the weight attribute, the local preference attribute is propagated
throughout the local AS. If there are multiple exit points from the AS, the
local preference attribute is used to select the exit point for a specific
route.
Multi-Exit Discriminator Attribute
The multi-exit discriminator
(MED) or metric attribute is used as a
suggestion to an external AS regarding the preferred route into the AS that is
advertising the metric.
The term suggestion is used
because the external AS that is receiving the MEDs may be using other BGP
attributes for route selection.
Origin Attribute
The origin attribute
indicates how BGP learned about a particular route. The origin attribute can
have one of three possible values:
·
IGP—The route is interior to the originating AS. This value is
set when the network router configuration command is used to inject the route
into BGP.
- EGP—The route is learned via the Exterior Border Gateway Protocol (EBGP).
- Incomplete—The origin of the route is unknown or learned in some other way. An origin of incomplete occurs when a route is redistributed into BGP.
AS_ path Attribute
When a route advertisement passes through an autonomous
system, the AS number is added to an ordered list of AS numbers that the route
advertisement has traversed.
Next-Hop Attribute
The EBGP next-hop attribute
is the IP address that is used to reach the advertising router. For EBGP peers,
the next-hop address is the IP address of the connection between the peers. For
IBGP, the EBGP next-hop address is carried into the local AS.
Community Attribute
The community attribute provides a way of grouping
destinations, called communities, to which routing decisions (such as
acceptance, preference, and redistribution) can be applied. Route maps are used
to set the community attribute. Predefined community attributes are listed here:
·
No-export—Do not advertise this route to EBGP peers.
- No-advertise—Do not advertise this route to any peer.
- Internet—Advertise this route to the Internet community; all
routers in the network belong to it.
BGP Path Selection
BGP could possibly receive multiple advertisements for the
same route from multiple sources. BGP selects only one path as the best path.
When the path is selected, BGP puts the selected path in the IP routing table
and propagates the path to its neighbors. BGP uses the following criteria, in
the order presented, to select a path for a destination:
·
If the path specifies a next hop that is inaccessible, drop
the update.
- Prefer the path with the largest weight.
- If the weights are the same, prefer the path with the
largest local preference.
- If the local preferences are the same, prefer the path
that was originated by BGP running on this router.
- If no route was originated, prefer the route that has the
shortest AS_path. If all paths have the same AS_path length, prefer the path
with the lowest origin type (where IGP is lower than EGP, and EGP is lower
than incomplete).
- If the origin codes are the same, prefer the path with
the lowest MED attribute.
- If the paths have the same MED, prefer the external path
over the internal path.
- If the paths are still the same, prefer the path through the closest IGP neighbor.
- Prefer the path with the lowest IP address, as specified by the BGP router ID
Configuration
Backbone_router7#show config
Using 8777 out of 32762 bytes
!
version 11.1
service password-encryption
service udp-small-servers
service tcp-small-servers
!
hostname Backbone_router7
!
enable secret 5 $1$u1YM$H90psI59kT6w73dBTOffZ.
!
username wniaz privilege 15 password 7 01070F035E19555D70
username ksaleem privilege 3 password 7 0958470E1C1744405A
no ip domain-lookup
!
interface Loopback0
ip address 192.168.226.1 255.255.255.255
!
interface Loopback1
ip address 192.168.228.1 255.255.255.255
!
interface Loopback2
ip address 192.168.230.1 255.255.255.255
!
interface Loopback3
ip address 192.168.235.1 255.255.255.255
!
interface Loopback4
ip address 192.168.238.1 255.255.255.255
!
interface Loopback5
ip address 192.168.239.1 255.255.255.255
!
interface Loopback6
ip address 192.168.240.1 255.255.255.255
!
interface Loopback7
ip address 192.168.243.1 255.255.255.255
!
interface Loopback8
ip address 192.168.245.1 255.255.255.255
!
interface Loopback9
ip address 192.168.250.1 255.255.255.255
!
interface Loopback10
ip address 192.168.254.1 255.255.255.255
!
interface Loopback11
ip address 172.24.1.1 255.255.255.255
!
interface Loopback12
ip address 172.24.10.1 255.255.255.255
!
interface Loopback13
ip address 172.24.15.1 255.255.255.255
!
interface Loopback14
ip address 172.24.211.1 255.255.255.255
!
interface Loopback15
ip address 172.24.250.1 255.255.255.255
!
interface Loopback16
ip address 172.27.1.1 255.255.255.255
!
interface Loopback17
ip address 172.27.15.1 255.255.255.255
!
interface Loopback18
ip address 172.27.115.1 255.255.255.255
!
interface Loopback19
ip address 172.27.190.1 255.255.255.255
!
interface Loopback20
ip address 172.27.211.1 255.255.255.255
!
interface Loopback21
ip address 172.27.245.1 255.255.255.255
!
interface Loopback22
ip address 172.30.1.1 255.255.255.255
!
interface Loopback23
ip address 172.30.20.1 255.255.255.255
!
interface Loopback24
ip address 172.30.31.1 255.255.255.255
!
interface Loopback25
ip address 172.30.161.1 255.255.255.255
!
interface Loopback26
ip address 172.30.101.1 255.255.255.255
!
interface Loopback27
ip address 172.30.191.1 255.255.255.255
!
interface Loopback28
ip address 172.30.211.1 255.255.255.255
!
interface Loopback29
ip address 172.30.231.1 255.255.255.255
!
interface Loopback30
ip address 172.30.251.1 255.255.255.255
!
interface Loopback31
ip address 10.18.1.1 255.255.255.255
!
interface Loopback32
ip address 10.18.27.1 255.255.255.255
!
interface Loopback33
ip address 10.18.56.1 255.255.255.255
!
interface Loopback34
ip address 10.18.69.1 255.255.255.255
!
interface Loopback35
ip address 10.18.85.1 255.255.255.255
!
interface Loopback36
ip address 10.18.179.1 255.255.255.255
!
interface Loopback37
ip address 10.18.127.1 255.255.255.255
!
interface Loopback38
ip address 10.18.238.1 255.255.255.255
!
interface Loopback39
ip address 10.18.152.1 255.255.255.255
!
interface Loopback40
ip address 10.18.200.1 255.255.255.255
!
interface Loopback41
ip address 10.21.1.25 255.255.255.255
!
interface Loopback42
ip address 10.21.10.25 255.255.255.255
!
interface Loopback43
ip address 10.21.111.25 255.255.255.255
!
interface Loopback44
ip address 10.21.125.25 255.255.255.255
!
interface Loopback45
ip address 10.21.221.25 255.255.255.255
!
interface Loopback46
ip address 10.21.135.25 255.255.255.255
!
interface Loopback47
ip address 10.21.251.25 255.255.255.255
!
interface Loopback48
ip address 10.21.211.25 255.255.255.255
!
interface Loopback49
ip address 10.21.132.25 255.255.255.255
!
interface Loopback50
ip address 10.21.91.25 255.255.255.255
!
interface Loopback51
ip address 10.25.1.55 255.255.255.255
!
interface Loopback52
ip address 10.25.51.55 255.255.255.255
!
interface Loopback53
ip address 10.25.21.55 255.255.255.255
!
interface Loopback54
ip address 10.25.32.55 255.255.255.255
!
interface Loopback55
ip address 10.25.98.55 255.255.255.255
!
interface Loopback56
ip address 10.25.159.55 255.255.255.255
!
interface Loopback57
ip address 10.25.254.55 255.255.255.255
!
interface Loopback58
ip address 10.25.108.55 255.255.255.255
!
interface Loopback59
ip address 10.25.212.55 255.255.255.255
!
interface Loopback60
ip address 10.25.145.55 255.255.255.255
!
interface Loopback61
ip address 172.31.109.1 255.255.255.0
!
interface Loopback62
ip address 10.10.0.1 255.255.255.255
!
interface Loopback63
ip address 10.10.50.1 255.255.255.255
!
interface Loopback64
ip address 10.10.100.1 255.255.255.255
!
interface Loopback65
ip address 10.10.150.1 255.255.255.255
!
interface Loopback66
ip address 10.10.200.1 255.255.255.255
!
interface Loopback67
ip address 10.16.0.1 255.255.255.255
!
interface Loopback68
ip address 10.16.250.1 255.255.255.255
!
interface Loopback69
ip address 10.16.113.1 255.255.255.255
!
interface Loopback70
ip address 10.16.199.1 255.255.255.255
!
interface Loopback71
ip address 10.19.0.1 255.255.255.255
!
interface Loopback72
ip address 10.19.50.1 255.255.255.255
!
interface Loopback73
ip address 10.19.100.1 255.255.255.255
!
interface Loopback74
ip address 10.19.251.1 255.255.255.255
!
interface Loopback75
ip address 10.23.1.1 255.255.255.255
!
interface Loopback76
ip address 10.23.15.1 255.255.255.255
!
interface Loopback77
ip address 10.23.250.1 255.255.255.255
!
interface Loopback78
ip address 10.26.0.1 255.255.255.255
!
interface Loopback79
ip address 10.26.100.1 255.255.255.255
!
interface Loopback80
ip address 10.26.45.1 255.255.255.255
!
interface Loopback81
ip address 10.26.220.1 255.255.255.255
!
interface Ethernet0
description Connected to port 0/5 CAT2900
ip address 192.168.1.18 255.255.255.252
!
interface Ethernet1
ip address 65.86.254.130 255.255.255.240
!
interface Serial0
ip address 192.168.129.13 255.255.255.252
ip ospf message-digest-key 1 md5 7 01100F175804
!
interface Serial1
description Connection to BackBone2523
ip address 192.168.129.9 255.255.255.252
clockrate 125000
!
router eigrp 65500
redistribute connected
redistribute static
network 192.168.129.0
no auto-summary
!
router bgp 65500
no synchronization
bgp dampening
network 192.168.128.0 mask 255.255.128.0
network 172.22.0.0
network 172.23.0.0
network 172.24.0.0
network 172.25.0.0
network 172.26.0.0
network 172.27.0.0
network 172.28.0.0
network 172.29.0.0
network 172.30.0.0
network 172.31.0.0
network 10.10.0.0 mask 255.255.0.0
network 10.16.0.0 mask 255.255.0.0
network 10.17.0.0 mask 255.255.0.0
network 10.18.0.0 mask 255.255.0.0
network 10.19.0.0 mask 255.255.0.0
network 10.20.0.0 mask 255.255.0.0
network 10.21.0.0 mask 255.255.0.0
network 10.22.0.0 mask 255.255.0.0
network 10.23.0.0 mask 255.255.0.0
network 10.24.0.0 mask 255.255.0.0
network 10.25.0.0 mask 255.255.0.0
network 10.26.0.0 mask 255.255.0.0
neighbor ibgp01-peer peer-group
neighbor ibgp01-peer remote-as 65500
neighbor ibgp01-peer update-source Loopback0
neighbor ibgp01-peer next-hop-self
neighbor ibgp01-peer send-community
neighbor 192.168.1.17 remote-as 65000
neighbor 192.168.1.17 send-community
neighbor 192.168.130.1 peer-group ibgp01-peer
neighbor 192.168.183.1 peer-group ibgp01-peer
no auto-summary
!
ip classless
ip route 10.10.0.0 255.255.0.0 Null0 250
ip route 10.16.0.0 255.255.0.0 Null0 250
ip route 10.17.0.0 255.255.0.0 Null0 250
ip route 10.18.0.0 255.255.0.0 Null0 250
ip route 10.20.0.0 255.255.0.0 Null0 250
ip route 10.21.0.0 255.255.0.0 Null0 250
ip route 10.22.0.0 255.255.0.0 Null0 250
ip route 10.23.0.0 255.255.0.0 Null0 250
ip route 10.24.0.0 255.255.0.0 Null0 250
ip route 10.25.0.0 255.255.0.0 Null0 250
ip route 10.26.0.0 255.255.0.0 Null0 250
ip route 172.22.0.0 255.255.0.0 Null0 250
ip route 172.23.0.0 255.255.0.0 Null0 250
ip route 172.24.0.0 255.255.0.0 Null0 250
ip route 172.25.0.0 255.255.0.0 Null0 250
ip route 172.26.0.0 255.255.0.0 Null0 250
ip route 172.27.0.0 255.255.0.0 Null0 250
ip route 172.29.0.0 255.255.0.0 Null0 250
ip route 172.30.0.0 255.255.0.0 Null0 250
ip route 172.31.0.0 255.255.0.0 Null0 250
ip route 192.168.128.0 255.255.128.0 Null0 250
ip route 209.87.64.73 255.255.255.255 65.86.254.129
banner exec ^CC
P L E A S E N O T E
It is VERY IMPORTANT to log out completely after using this device.
WAJAHAT ALI NIAZ is the owner and administrator. Make sure you have
permission from him to use this system.^C
banner motd ^CC
WARNING*************************WARNING******************************WARNING
If you are not authorized to access this system, disconnect now.All attempts
to access and use of this system are subject to key stroke monitoring.Unauthorized
access attempts or use may subject you to a fine and imprisonment.
WARNING****************************WARNING***************************WARNING^C
!
line con 0
line aux 0
line vty 0 4
exec-timeout 0 0
password 7 030752180500
login
!
end
Backbone_router7#192.168.129.14
Trying 192.168.129.14 ... Open
C
WARNING*************************WARNING******************************WARNING
If you are not authorized to access this system, disconnect now.All attempts
to access and use of this system are subject to key stroke monitoring.Unauthorized
access attempts or use may subject you to a fine and imprisonment.
WARNING****************************WARNING***************************WARNING
User Access Verification
Password: C
P L E A S E N O T E
It is VERY IMPORTANT to log out completely after using this device.
WAJAHAT ALI NIAZ is the owner and administrator. Make sure you have
permission from him to use this system.
Router4>en
Password:
Router4#show config
Using 6519 out of 32762 bytes
!
version 11.3
service timestamps debug uptime
service timestamps log uptime
service password-encryption
!
hostname Router4
!
enable secret 5 $1$uGJ5$lk/B9VTPrjurr5nnC.55I.
!
ip subnet-zero
!
!
!
!
process-max-time 200
!
interface Loopback0
ip address 192.168.183.1 255.255.255.255
!
interface Loopback1
ip address 192.168.185.1 255.255.255.255
!
interface Loopback2
ip address 192.168.189.1 255.255.255.255
!
interface Loopback3
ip address 192.168.193.1 255.255.255.255
!
interface Loopback4
ip address 192.168.194.1 255.255.255.255
!
interface Loopback5
ip address 192.168.195.1 255.255.255.255
!
interface Loopback6
ip address 192.168.196.1 255.255.255.255
!
interface Loopback7
ip address 192.168.197.1 255.255.255.255
!
interface Loopback8
ip address 192.168.199.1 255.255.255.255
!
interface Loopback9
ip address 192.168.200.1 255.255.255.255
!
interface Loopback10
ip address 192.168.201.1 255.255.255.255
!
interface Loopback11
ip address 192.168.203.1 255.255.255.255
!
interface Loopback12
ip address 192.168.204.1 255.255.255.255
!
interface Loopback13
ip address 192.168.205.1 255.255.255.255
!
interface Loopback14
ip address 192.168.206.1 255.255.255.255
!
interface Loopback15
ip address 192.168.207.1 255.255.255.255
!
interface Loopback16
ip address 192.168.210.1 255.255.255.255
!
interface Loopback17
ip address 192.168.211.1 255.255.255.255
!
interface Loopback18
ip address 192.168.212.1 255.255.255.255
!
interface Loopback19
ip address 192.168.213.1 255.255.255.255
!
interface Loopback20
ip address 192.168.220.1 255.255.255.255
!
interface Loopback21
ip address 172.23.0.1 255.255.255.255
!
interface Loopback22
ip address 172.23.100.1 255.255.255.255
!
interface Loopback23
ip address 172.23.200.1 255.255.255.255
!
interface Loopback24
ip address 172.23.250.1 255.255.255.255
!
interface Loopback25
ip address 172.23.20.1 255.255.255.255
!
interface Loopback26
ip address 172.26.10.1 255.255.255.255
!
interface Loopback27
ip address 172.26.100.1 255.255.255.255
!
interface Loopback28
ip address 172.26.150.1 255.255.255.255
!
interface Loopback29
ip address 172.26.201.1 255.255.255.255
!
interface Loopback30
ip address 172.26.245.1 255.255.255.255
!
interface Loopback31
ip address 172.29.10.1 255.255.255.255
!
interface Loopback32
ip address 172.29.199.1 255.255.255.255
!
interface Loopback33
ip address 172.29.25.1 255.255.255.255
!
interface Loopback34
ip address 172.29.50.1 255.255.255.255
!
interface Loopback35
ip address 172.29.75.1 255.255.255.255
!
interface Loopback36
ip address 172.29.100.1 255.255.255.255
!
interface Loopback37
ip address 172.29.109.1 255.255.255.255
!
interface Loopback38
ip address 172.29.160.1 255.255.255.255
!
interface Loopback39
ip address 172.29.190.1 255.255.255.255
!
interface Loopback40
ip address 172.29.200.1 255.255.255.255
!
interface Loopback49
ip address 172.29.245.1 255.255.255.255
!
interface Loopback50
ip address 172.29.250.1 255.255.255.255
!
interface Loopback51
ip address 10.17.0.1 255.255.255.255
!
interface Loopback52
ip address 10.17.10.1 255.255.255.255
!
interface Loopback53
ip address 10.17.110.1 255.255.255.255
!
interface Loopback54
ip address 10.17.254.1 255.255.255.255
!
interface Loopback55
ip address 10.17.230.1 255.255.255.255
!
interface Loopback56
ip address 10.17.150.1 255.255.255.255
!
interface Loopback57
ip address 10.17.14.1 255.255.255.255
!
interface Loopback58
ip address 10.17.100.1 255.255.255.255
!
interface Loopback59
ip address 10.17.119.1 255.255.255.255
!
interface Loopback60
ip address 10.22.0.1 255.255.255.255
!
interface Loopback61
ip address 10.22.9.1 255.255.255.255
!
interface Loopback62
ip address 10.22.29.1 255.255.255.255
!
interface Loopback63
ip address 10.22.45.1 255.255.255.255
!
interface Loopback64
ip address 10.22.79.1 255.255.255.255
!
interface Loopback65
ip address 10.22.243.1 255.255.255.255
!
interface Loopback66
ip address 10.22.129.1 255.255.255.255
!
interface Loopback67
ip address 10.22.250.1 255.255.255.255
!
interface Loopback68
ip address 10.22.107.1 255.255.255.255
!
interface Loopback69
ip address 10.22.177.1 255.255.255.255
!
interface Loopback70
ip address 10.22.199.1 255.255.255.255
!
interface Loopback71
ip address 10.24.1.1 255.255.255.255
!
interface Loopback72
ip address 10.24.11.1 255.255.255.255
!
interface Loopback73
ip address 10.24.19.1 255.255.255.255
!
interface Loopback74
ip address 10.24.31.1 255.255.255.255
!
interface Loopback75
ip address 10.24.41.1 255.255.255.255
!
interface Loopback76
ip address 10.24.111.1 255.255.255.255
!
interface Loopback77
ip address 10.24.121.1 255.255.255.255
!
interface Loopback78
ip address 10.24.200.1 255.255.255.255
!
interface Loopback79
ip address 10.24.225.1 255.255.255.255
!
interface Loopback80
ip address 10.24.254.1 255.255.255.255
!
interface Ethernet0
no ip address
!
interface Serial0
ip address 10.21.1.2 255.255.255.252
clockrate 125000
!
interface Serial1
ip address 192.168.129.14 255.255.255.252
clockrate 125000
!
interface TokenRing0
ip address 10.1.1.1 255.255.255.0
shutdown
ring-speed 16
!
router eigrp 65500
redistribute connected
passive-interface Serial0
network 192.168.129.0
default-metric 1544 20000 255 1 1500
no auto-summary
!
router rip
version 2
redistribute connected
redistribute static
passive-interface Serial1
network 10.0.0.0
no auto-summary
!
router bgp 65500
no synchronization
bgp dampening
neighbor ibgp01-peer peer-group
neighbor ibgp01-peer remote-as 65500
neighbor ibgp01-peer update-source Loopback0
neighbor ibgp01-peer next-hop-self
neighbor ibgp01-peer send-community
neighbor 192.168.130.1 peer-group ibgp01-peer
neighbor 192.168.226.1 peer-group ibgp01-peer
no auto-summary
!
ip classless
!
banner exec ^CC
P L E A S E N O T E
It is VERY IMPORTANT to log out completely after using this device.
WAJAHAT ALI NIAZ is the owner and administrator. Make sure you have
permission from him to use this system.^C
banner motd ^CC
WARNING*************************WARNING******************************WARNING
If you are not authorized to access this system, disconnect now.All attempts
to access and use of this system are subject to key stroke monitoring.Unauthorized
access attempts or use may subject you to a fine and imprisonment.
WARNING****************************WARNING***************************WARNING^C
!
line con 0
transport input none
line aux 0
line vty 0 4
password 7 110A1016141D
login
!
end
Router4#exit
[Connection to 192.168.129.14 closed by foreign host]
Backbone_router7#192.168.129.10
Trying 192.168.129.10 ... Open
WARNING*************************WARNING******************************WARNING
If you are not authorized to access this system, disconnect now.All attempts
to access and use of this system are subject to key stroke monitoring.Unauthorized
access attempts or use may subject you to a fine and imprisonment.
WARNING****************************WARNING***************************WARNINGWelcome user
User Access Verification
Password:
P L E A S E N O T E
It is VERY IMPORTANT to log out completely after using this device.
WAJAHAT ALI NIAZ is the owner and administrator. Make sure you have
permission from him to use this system.
Router6>en
Password:
Router6#sh config
Using 9985 out of 32762 bytes
!
version 11.3
service timestamps debug uptime
service timestamps log uptime
service password-encryption
service udp-small-servers
service tcp-small-servers
!
hostname Router6
!
enable secret 5 $1$uGJ5$lk/B9VTPrjurr5nnC.55I.
enable password 7 14141B180F0B
!
username wniaz privilege 15 password 7 01070F035E19555D70
username ksaleem privilege 3 password 7 0958470E1C1744405A
ip subnet-zero
!
!
!
!
process-max-time 200
!
interface Loopback0
ip address 192.168.130.1 255.255.255.255
no ip directed-broadcast
!
interface Loopback2
ip address 192.168.131.1 255.255.255.255
!
interface Loopback3
ip address 192.168.132.1 255.255.255.255
!
interface Loopback4
ip address 192.168.133.1 255.255.255.255
!
interface Loopback5
ip address 192.168.134.1 255.255.255.255
!
interface Loopback6
ip address 192.168.135.1 255.255.255.255
!
interface Loopback7
ip address 192.168.136.1 255.255.255.255
!
interface Loopback8
ip address 192.168.137.1 255.255.255.255
!
interface Loopback9
ip address 192.168.138.1 255.255.255.255
!
interface Loopback10
ip address 192.168.141.1 255.255.255.255
!
interface Loopback11
ip address 192.168.142.1 255.255.255.255
!
interface Loopback12
ip address 192.168.143.1 255.255.255.255
!
interface Loopback13
ip address 192.168.144.1 255.255.255.255
!
interface Loopback14
ip address 192.168.145.1 255.255.255.255
!
interface Loopback15
ip address 192.168.146.1 255.255.255.255
!
interface Loopback16
ip address 192.168.147.1 255.255.255.255
!
interface Loopback17
ip address 192.168.148.1 255.255.255.255
!
interface Loopback18
ip address 192.168.149.1 255.255.255.255
!
interface Loopback19
ip address 192.168.150.1 255.255.255.255
!
interface Loopback20
ip address 192.168.151.1 255.255.255.255
!
interface Loopback21
ip address 192.168.152.1 255.255.255.255
!
interface Loopback22
ip address 192.168.153.1 255.255.255.255
!
interface Loopback23
ip address 192.168.154.1 255.255.255.255
!
interface Loopback24
ip address 192.168.155.1 255.255.255.255
!
interface Loopback25
ip address 192.168.156.1 255.255.255.255
!
interface Loopback26
ip address 192.168.157.1 255.255.255.255
!
interface Loopback27
ip address 192.168.158.1 255.255.255.255
!
interface Loopback28
ip address 192.168.159.1 255.255.255.255
!
interface Loopback29
ip address 192.168.160.1 255.255.255.255
!
interface Loopback30
ip address 192.168.161.1 255.255.255.255
!
interface Loopback31
ip address 192.168.162.1 255.255.255.255
!
interface Loopback32
ip address 192.168.163.1 255.255.255.255
!
interface Loopback33
ip address 192.168.164.1 255.255.255.255
!
interface Loopback34
ip address 192.168.165.1 255.255.255.255
!
interface Loopback35
ip address 192.168.166.1 255.255.255.255
!
interface Loopback36
ip address 192.168.167.1 255.255.255.255
!
interface Loopback37
ip address 192.168.168.1 255.255.255.255
!
interface Loopback38
ip address 192.168.169.1 255.255.255.255
!
interface Loopback39
ip address 192.168.170.1 255.255.255.255
!
interface Loopback40
ip address 192.168.171.1 255.255.255.255
!
interface Loopback41
ip address 192.168.173.1 255.255.255.255
!
interface Loopback42
ip address 192.168.180.1 255.255.255.255
!
interface Loopback43
ip address 192.168.174.1 255.255.255.255
!
interface Loopback44
ip address 192.168.178.1 255.255.255.255
!
interface Loopback45
ip address 192.168.181.1 255.255.255.255
!
interface Loopback46
ip address 192.168.182.1 255.255.255.255
!
interface Loopback47
ip address 192.168.254.1 255.255.255.255
!
interface Loopback48
ip address 192.168.253.1 255.255.255.255
!
interface Loopback49
ip address 172.22.1.1 255.255.255.0
!
interface Loopback50
ip address 172.22.3.1 255.255.255.0
!
interface Loopback51
ip address 172.22.4.1 255.255.255.0
!
interface Loopback52
ip address 172.22.5.1 255.255.255.0
!
interface Loopback53
ip address 172.22.10.1 255.255.255.0
!
interface Loopback54
ip address 172.22.11.1 255.255.255.0
!
interface Loopback55
ip address 172.22.12.1 255.255.255.0
!
interface Loopback56
ip address 172.22.13.1 255.255.255.0
!
interface Loopback57
ip address 172.22.21.1 255.255.255.0
!
interface Loopback58
ip address 172.22.55.1 255.255.255.0
!
interface Loopback59
ip address 172.22.60.1 255.255.255.0
!
interface Loopback60
ip address 172.22.70.1 255.255.255.0
!
interface Loopback61
ip address 172.22.73.1 255.255.255.0
!
interface Loopback62
ip address 172.22.75.1 255.255.255.0
!
interface Loopback63
ip address 172.22.80.1 255.255.255.0
!
interface Loopback64
ip address 172.22.90.1 255.255.255.0
!
interface Loopback65
ip address 172.22.100.1 255.255.255.0
!
interface Loopback66
ip address 172.22.254.1 255.255.255.0
!
interface Loopback67
ip address 172.22.200.1 255.255.255.0
!
interface Loopback68
ip address 172.22.154.1 255.255.255.0
!
interface Loopback69
ip address 172.25.0.1 255.255.255.0
!
interface Loopback70
ip address 172.25.1.1 255.255.255.0
!
interface Loopback71
ip address 172.25.5.1 255.255.255.0
!
interface Loopback72
ip address 172.25.10.1 255.255.255.0
!
interface Loopback73
ip address 172.25.15.1 255.255.255.0
!
interface Loopback74
ip address 172.25.20.1 255.255.255.0
!
interface Loopback75
ip address 172.25.31.1 255.255.255.0
!
interface Loopback76
ip address 172.25.33.1 255.255.255.0
!
interface Loopback77
ip address 172.25.100.1 255.255.255.0
!
interface Loopback78
ip address 172.25.120.1 255.255.255.0
!
interface Loopback79
ip address 172.25.125.1 255.255.255.0
!
interface Loopback80
ip address 172.25.150.1 255.255.255.0
!
interface Loopback81
ip address 172.25.200.1 255.255.255.0
!
interface Loopback82
ip address 172.25.254.1 255.255.255.0
!
interface Loopback83
ip address 172.28.225.1 255.255.255.0
!
interface Loopback84
ip address 172.28.215.1 255.255.255.0
!
interface Loopback85
ip address 172.28.0.1 255.255.255.0
!
interface Loopback86
ip address 172.31.1.1 255.255.255.0
!
interface Loopback87
ip address 172.31.10.1 255.255.255.0
!
interface Loopback88
ip address 172.31.20.1 255.255.255.0
!
interface Loopback89
ip address 172.31.31.1 255.255.255.0
!
interface Loopback90
ip address 172.31.50.1 255.255.255.0
!
interface Loopback91
ip address 172.31.100.1 255.255.255.0
!
interface Loopback92
ip address 172.31.150.1 255.255.255.0
!
interface Loopback93
ip address 172.31.170.1 255.255.255.0
!
interface Loopback94
ip address 172.31.200.1 255.255.255.0
!
interface Loopback95
ip address 172.31.250.1 255.255.255.0
!
interface Loopback96
ip address 172.31.233.1 255.255.255.0
!
interface Loopback97
ip address 172.31.240.1 255.255.255.0
!
interface Loopback98
ip address 172.31.220.84 255.255.255.255
!
interface Loopback99
ip address 172.31.33.1 255.255.255.0
!
interface Serial0
ip address 10.21.1.1 255.255.255.252
no ip redirects
no ip directed-broadcast
no ip proxy-arp
no ip route-cache
ip ospf message-digest-key 1 md5 7 01100F175804
no ip mroute-cache
!
interface Serial1
ip address 192.168.129.10 255.255.255.252
no ip redirects
no ip directed-broadcast
no ip proxy-arp
no ip route-cache
ip ospf message-digest-key 1 md5 7 01100F175804
no ip mroute-cache
!
interface Serial2
no ip address
no ip directed-broadcast
no ip route-cache
ip ospf message-digest-key 1 md5 7 01100F175804
no ip mroute-cache
clockrate 64000
!
interface Serial3
no ip address
no ip directed-broadcast
no ip route-cache
ip ospf message-digest-key 1 md5 7 01100F175804
no ip mroute-cache
shutdown
clockrate 64000
!
interface Serial4
no ip address
no ip directed-broadcast
no ip route-cache
no ip mroute-cache
shutdown
!
interface Serial5
no ip address
no ip directed-broadcast
no ip route-cache
no ip mroute-cache
shutdown
!
interface Serial6
no ip address
no ip directed-broadcast
no ip route-cache
no ip mroute-cache
shutdown
!
interface Serial7
no ip address
no ip directed-broadcast
no ip route-cache
no ip mroute-cache
shutdown
!
interface Serial8
no ip address
no ip directed-broadcast
no ip route-cache
no ip mroute-cache
shutdown
!
interface Serial9
no ip address
no ip directed-broadcast
no ip route-cache
no ip mroute-cache
shutdown
!
interface TokenRing0
no ip address
no ip directed-broadcast
no ip route-cache
no ip mroute-cache
shutdown
ring-speed 16
!
interface BRI0
no ip address
no ip directed-broadcast
no ip route-cache
no ip mroute-cache
!
router eigrp 65500
redistribute connected
redistribute rip
passive-interface Serial0
network 192.168.129.0
default-metric 1544 20000 255 1 1500
no auto-summary
!
router rip
version 2
redistribute connected
redistribute static
redistribute eigrp 65500
passive-interface Serial1
network 10.0.0.0
no auto-summary
!
router bgp 65500
no synchronization
bgp dampening
neighbor ibgp01-peer peer-group
neighbor ibgp01-peer remote-as 65500
neighbor ibgp01-peer update-source Loopback0
neighbor ibgp01-peer next-hop-self
neighbor ibgp01-peer send-community
neighbor 192.168.183.1 peer-group ibgp01-peer
neighbor 192.168.226.1 peer-group ibgp01-peer
no auto-summary
!
ip classless
!
banner exec ^C
P L E A S E N O T E
It is VERY IMPORTANT to log out completely after using this device.
WAJAHAT ALI NIAZ is the owner and administrator. Make sure you have
permission from him to use this system.^C
banner login ^CWelcome user^C
banner motd ^C
WARNING*************************WARNING******************************WARNING
If you are not authorized to access this system, disconnect now.All attempts
to access and use of this system are subject to key stroke monitoring.Unauthorized
access attempts or use may subject you to a fine and imprisonment.
WARNING****************************WARNING***************************WARNING^C
!
line con 0
password 7 121A0C041104
transport input none
line aux 0
password 7 00071A150754
login
modem InOut
transport input all
stopbits 1
flowcontrol hardware
line vty 0 3
password 7 045802150C2E
login
line vty 4
exec-timeout 0 0
password 7 045802150C2E
login
!
end
Router6#exit
[Connection to 192.168.129.10 closed by foreign host]
Backbone_router7#exit
Connection closed by foreign host.
[wniaz@saranac wniaz]$ exit
logout
[wniaz@saranac wniaz]$ telnet 65.86.254.131
Trying 65.86.254.131...
Connected to 65.86.254.131.
Escape character is '^]'.
User Access Verification
Password:
Router1>en
Password:
Password:
Router1#show runn
Building configuration...
Current configuration:
!
version 11.3
service timestamps debug uptime
service timestamps log uptime
no service password-encryption
!
hostname Router1
!
enable secret 5 $1$y2gK$yZCQPXA/1oaX1INFMCDQu/
!
ip subnet-zero
!
!
!
!
process-max-time 200
!
interface Loopback0
ip address 172.16.1.1 255.255.255.255
!
interface Loopback2
ip address 172.16.2.1 255.255.255.255
!
interface Loopback3
ip address 172.16.3.1 255.255.255.255
!
interface Loopback4
ip address 172.16.4.1 255.255.255.255
!
interface Loopback5
ip address 172.16.5.1 255.255.255.255
!
interface Loopback6
ip address 172.16.6.1 255.255.255.255
!
interface Loopback7
ip address 172.16.7.1 255.255.255.255
!
interface Loopback8
ip address 172.16.8.1 255.255.255.255
!
interface Loopback9
ip address 172.16.9.1 255.255.255.255
!
interface Loopback10
ip address 172.16.10.1 255.255.255.255
!
interface Loopback11
ip address 172.16.11.1 255.255.255.255
!
interface Loopback12
ip address 172.16.12.1 255.255.255.255
!
interface Loopback13
ip address 172.16.13.1 255.255.255.255
!
interface Loopback14
ip address 172.16.14.1 255.255.255.255
!
interface Loopback15
ip address 172.16.15.1 255.255.255.255
!
interface Loopback16
ip address 10.0.0.1 255.255.255.255
!
interface Loopback17
ip address 10.0.1.1 255.255.255.255
!
interface Loopback18
ip address 10.0.2.1 255.255.255.255
!
interface Loopback19
ip address 10.0.4.1 255.255.255.255
!
interface Loopback20
ip address 10.0.5.1 255.255.255.255
!
interface Loopback21
ip address 10.0.6.1 255.255.255.255
!
interface Loopback22
ip address 10.0.7.1 255.255.255.255
!
interface Loopback23
ip address 10.0.8.1 255.255.255.255
!
interface Loopback24
ip address 10.0.9.1 255.255.255.255
!
interface Loopback25
ip address 10.0.10.1 255.255.255.255
!
interface Loopback26
ip address 10.0.253.1 255.255.255.255
!
interface Loopback27
ip address 172.16.27.1 255.255.255.255
!
interface Loopback28
ip address 172.16.28.1 255.255.255.255
!
interface Loopback29
no ip address
!
interface Loopback30
ip address 172.16.29.1 255.255.255.255
!
interface Loopback31
ip address 192.168.2.1 255.255.255.255
!
interface Loopback32
ip address 192.168.3.1 255.255.255.255
!
interface Loopback33
ip address 192.168.4.1 255.255.255.255
!
interface Loopback34
ip address 192.168.5.1 255.255.255.255
!
interface Loopback35
ip address 192.168.6.1 255.255.255.255
!
interface Loopback36
ip address 192.168.7.1 255.255.255.255
!
interface Loopback37
ip address 192.168.8.1 255.255.255.255
!
interface Loopback38
ip address 192.168.9.1 255.255.255.255
!
interface Loopback39
ip address 192.168.10.1 255.255.255.255
!
interface Loopback40
ip address 192.168.11.1 255.255.255.255
!
interface Loopback41
ip address 192.168.12.1 255.255.255.255
!
interface Loopback42
ip address 192.168.13.1 255.255.255.255
!
interface Loopback43
ip address 192.168.14.1 255.255.255.255
!
interface Loopback44
ip address 192.168.15.1 255.255.255.255
!
interface Loopback45
ip address 192.168.16.1 255.255.255.255
!
interface Loopback46
ip address 192.168.17.1 255.255.255.255
!
interface Loopback47
ip address 192.168.122.1 255.255.255.255
!
interface Loopback48
ip address 192.168.123.1 255.255.255.255
!
interface Loopback49
ip address 192.168.124.1 255.255.255.255
!
interface Loopback50
ip address 192.168.126.1 255.255.255.0
!
interface Ethernet0
ip address 65.86.254.131 255.255.255.240
!
interface Serial0
ip address 192.168.1.2 255.255.255.252
no ip mroute-cache
!
interface Serial1
no ip address
shutdown
!
router ospf 1
redistribute connected subnets
redistribute static subnets
passive-interface Ethernet0
network 192.168.1.0 0.0.0.3 area 1
!
ip classless
ip route 209.87.64.73 255.255.255.255 65.86.254.129
!
tftp-server flash c2500-is56i-l.113-11b.T2.bin
!
line con 0
line aux 0
line vty 0 3
password cisco
login
line vty 4
exec-timeout 0 0
password cisco
login
!
end
Router1#192.168.1.1
Trying 192.168.1.1 ... Open
WARNING*************************WARNING******************************WARNING
If you are not authorized to access this system, disconnect now.All attempts
to access and use of this system are subject to key stroke monitoring.Unauthorized
access attempts or use may subject you to a fine and imprisonment.
WARNING****************************WARNING***************************WARNING
User Access Verification
Password:
Password:
P L E A S E N O T E
It is VERY IMPORTANT to log out completely after using this device.
WAJAHAT ALI NIAZ is the owner and administrator. Make sure you have
permission from him to use this system.
Router2>en
Password:
Router2#show runn
Building configuration...
Current configuration:
!
version 11.3
service timestamps debug uptime
service timestamps log uptime
service password-encryption
!
hostname Router2
!
enable secret 5 $1$uGJ5$lk/B9VTPrjurr5nnC.55I.
!
ip subnet-zero
no ip finger
!
!
crypto isakmp policy 10
hash md5
authentication pre-share
!
!
!
process-max-time 200
!
interface Loopback0
ip address 192.168.0.1 255.255.255.255
!
interface Ethernet0
ip address 192.168.1.17 255.255.255.252
!
interface Serial0
ip address 192.168.1.1 255.255.255.252
no ip mroute-cache
clockrate 64000
!
interface Serial1
ip address 192.168.1.5 255.255.255.252
no ip mroute-cache
clockrate 125000
!
interface Serial2
no ip address
no ip mroute-cache
!
interface Serial3
no ip address
no ip mroute-cache
!
interface Serial4
no ip address
shutdown
!
interface Serial5
no ip address
shutdown
!
interface Serial6
no ip address
shutdown
!
interface Serial7
no ip address
shutdown
!
interface Serial8
no ip address
shutdown
!
interface Serial9
no ip address
shutdown
!
interface BRI0
no ip address
shutdown
!
router ospf 1
redistribute connected subnets
redistribute static subnets
network 192.168.1.0 0.0.0.3 area 1
network 192.168.1.4 0.0.0.3 area 2
network 0.0.0.0 255.255.255.255 area 0
default-information originate always metric 5
!
router bgp 65000
no synchronization
bgp dampening
network 10.0.0.0 mask 255.255.252.0
network 10.0.253.0 mask 255.255.255.0
network 10.1.0.0 mask 255.255.0.0
network 10.2.0.0 mask 255.255.0.0
network 10.3.0.0 mask 255.255.0.0
network 10.4.0.0 mask 255.255.0.0
network 10.5.0.0 mask 255.255.0.0
network 10.6.0.0 mask 255.255.0.0
network 10.7.0.0 mask 255.255.0.0
network 10.8.0.0 mask 255.255.0.0
network 10.9.0.0 mask 255.255.0.0
network 10.11.0.0 mask 255.255.0.0
network 10.12.0.0 mask 255.255.0.0
network 10.13.0.0 mask 255.255.0.0
network 10.14.0.0 mask 255.255.0.0
network 10.15.0.0 mask 255.255.0.0
network 10.20.0.0 mask 255.255.0.0
network 172.16.0.0 mask 255.255.240.0
network 172.16.16.0 mask 255.255.240.0
network 172.16.200.0 mask 255.255.255.0
network 172.16.0.0
network 172.17.0.0
network 172.18.0.0
network 172.19.0.0
network 172.20.0.0
network 172.21.0.0
network 192.168.1.0
network 192.168.0.0 mask 255.255.128.0
neighbor ibgp-peer peer-group
neighbor ibgp-peer remote-as 65000
neighbor ibgp-peer update-source Loopback0
neighbor ibgp-peer next-hop-self
neighbor ibgp-peer send-community
neighbor 192.168.1.18 remote-as 65500
neighbor 192.168.1.18 send-community
neighbor 192.168.127.1 peer-group ibgp-peer
no auto-summary
!
ip http server
ip classless
ip route 10.0.0.0 255.255.252.0 Null0 250
ip route 10.0.253.0 255.255.255.0 Null0 250
ip route 10.1.0.0 255.255.0.0 Null0 250
ip route 10.2.0.0 255.255.0.0 Null0 250
ip route 10.3.0.0 255.255.0.0 Null0 250
ip route 10.4.0.0 255.255.0.0 Null0 250
ip route 10.5.0.0 255.255.0.0 Null0 250
ip route 10.6.0.0 255.255.0.0 Null0 250
ip route 10.7.0.0 255.255.0.0 Null0 250
ip route 10.8.0.0 255.255.0.0 Null0 250
ip route 10.9.0.0 255.255.0.0 Null0 250
ip route 10.11.0.0 255.255.0.0 Null0 250
ip route 10.12.0.0 255.255.0.0 Null0 250
ip route 10.13.0.0 255.255.0.0 Null0 250
ip route 10.14.0.0 255.255.0.0 Null0 250
ip route 10.15.0.0 255.255.0.0 Null0 250
ip route 10.20.0.0 255.255.0.0 Null0 250
ip route 172.16.0.0 255.255.0.0 Null0 250
ip route 172.16.0.0 255.255.240.0 Null0
ip route 172.16.16.0 255.255.240.0 Null0 250
ip route 172.16.200.0 255.255.255.0 Null0 250
ip route 172.17.0.0 255.255.0.0 Null0 250
ip route 172.18.0.0 255.255.0.0 Null0 250
ip route 172.19.0.0 255.255.0.0 Null0 250
ip route 172.20.0.0 255.255.0.0 Null0 250
ip route 172.21.0.0 255.255.0.0 Null0 250
ip route 192.168.0.0 255.255.128.0 Null0 250
ip route 192.168.1.0 255.255.255.0 Null0
ip route 192.168.1.0 255.255.255.0 Null0 250
!
banner exec ^C
P L E A S E N O T E
It is VERY IMPORTANT to log out completely after using this device.
WAJAHAT ALI NIAZ is the owner and administrator. Make sure you have
permission from him to use this system.^C
banner motd ^C
WARNING*************************WARNING******************************WARNING
If you are not authorized to access this system, disconnect now.All attempts
to access and use of this system are subject to key stroke monitoring.Unauthorized
access attempts or use may subject you to a fine and imprisonment.
WARNING****************************WARNING***************************WARNING^C
!
line con 0
transport input none
line aux 0
line vty 0 3
password 7 110A1016141D
login
line vty 4
exec-timeout 0 0
password 7 110A1016141D
login
!
end
Router2#sh ip int brie
Interface IP-Address OK? Method Status Protocol
BRI0 unassigned YES unset administratively down down
BRI0:1 unassigned YES unset administratively down down
BRI0:2 unassigned YES unset administratively down down
Ethernet0 192.168.1.17 YES NVRAM up up
Loopback0 192.168.0.1 YES NVRAM up up
Serial0 192.168.1.1 YES NVRAM up up
Serial1 192.168.1.5 YES NVRAM up up
Serial2 unassigned YES unset down down
Serial3 unassigned YES unset up down
Serial4 unassigned YES unset administratively down down
Serial5 unassigned YES unset administratively down down
Serial6 unassigned YES unset administratively down down
Serial7 unassigned YES unset administratively down down
Serial8 unassigned YES unset administratively down down
Serial9 unassigned YES unset administratively down down
Router2#192.168.1.6
Trying 192.168.1.6 ... Open
User Access Verification
Password:
Router3>en
Password:
Router3#show config
Using 4739 out of 32762 bytes
!
version 11.3
service timestamps debug uptime
service timestamps log uptime
no service password-encryption
!
hostname Router3
!
enable secret 5 $1$0vEN$yF0kQ9HlK7ZF4ruuVoJep/
enable password sanfran
!
!
!
!
interface Loopback0
ip address 192.168.127.1 255.255.255.255
!
interface Loopback1
ip address 172.16.17.1 255.255.255.255
!
interface Loopback2
ip address 172.16.18.1 255.255.255.255
!
interface Loopback3
ip address 172.16.19.1 255.255.255.255
!
interface Loopback4
ip address 172.16.20.1 255.255.255.255
!
interface Loopback5
ip address 172.16.22.1 255.255.255.255
!
interface Loopback6
ip address 172.16.200.1 255.255.255.255
!
interface Loopback7
ip address 172.16.23.1 255.255.255.255
!
interface Loopback8
ip address 172.16.24.1 255.255.255.255
!
interface Loopback9
ip address 172.16.25.1 255.255.255.255
!
interface Loopback10
ip address 172.16.26.1 255.255.255.255
!
interface Loopback11
ip address 172.17.101.1 255.255.255.255
!
interface Loopback12
ip address 172.18.1.1 255.255.255.255
!
interface Loopback13
ip address 172.19.1.1 255.255.255.255
!
interface Loopback14
ip address 172.20.101.1 255.255.255.255
!
interface Loopback15
ip address 172.21.1.101 255.255.255.255
!
interface Loopback16
ip address 172.21.2.1 255.255.255.255
!
interface Loopback17
ip address 172.21.3.1 255.255.255.255
!
interface Loopback18
ip address 172.21.4.1 255.255.255.255
!
interface Loopback19
ip address 172.21.5.1 255.255.255.255
!
interface Loopback20
ip address 172.21.63.1 255.255.255.255
!
interface Loopback21
ip address 10.1.0.1 255.255.255.255
!
interface Loopback22
ip address 10.2.0.1 255.255.255.255
!
interface Loopback23
ip address 10.3.0.1 255.255.255.255
!
interface Loopback24
ip address 10.4.0.1 255.255.255.255
!
interface Loopback25
ip address 10.5.0.1 255.255.255.255
!
interface Loopback26
ip address 10.6.0.1 255.255.255.255
!
interface Loopback27
ip address 10.7.0.1 255.255.255.255
!
interface Loopback29
ip address 10.8.0.1 255.255.255.255
!
interface Loopback30
ip address 10.9.0.1 255.255.255.255
!
interface Loopback31
ip address 10.9.9.1 255.255.255.255
!
interface Loopback32
ip address 10.11.0.1 255.255.255.255
!
interface Loopback33
ip address 10.12.0.1 255.255.255.255
!
interface Loopback34
ip address 10.13.0.1 255.255.255.255
!
interface Loopback35
ip address 10.14.0.1 255.255.255.255
!
interface Loopback36
ip address 10.15.0.1 255.255.255.255
!
interface Loopback37
ip address 10.20.0.1 255.255.255.255
!
interface Loopback38
ip address 10.14.100.1 255.255.255.255
!
interface Loopback39
ip address 10.13.101.1 255.255.255.255
!
interface Loopback40
ip address 10.12.101.1 255.255.255.255
!
interface Loopback41
ip address 10.8.101.1 255.255.255.255
!
interface Loopback42
ip address 10.8.100.1 255.255.255.255
!
interface Loopback43
ip address 10.8.99.1 255.255.255.255
!
interface Loopback44
ip address 192.168.18.1 255.255.255.255
!
interface Loopback45
ip address 192.168.121.1 255.255.255.255
!
interface Loopback46
ip address 192.168.117.1 255.255.255.255
!
interface Loopback47
ip address 192.168.125.1 255.255.255.255
!
interface Loopback48
ip address 192.168.113.1 255.255.255.255
!
interface Loopback49
ip address 172.16.16.1 255.255.255.255
!
interface Loopback50
ip address 192.168.20.1 255.255.255.255
!
interface Loopback51
ip address 192.168.21.1 255.255.255.255
!
interface Loopback52
ip address 192.168.22.1 255.255.255.255
!
interface Loopback53
ip address 192.168.32.1 255.255.255.255
!
interface Loopback54
ip address 192.168.33.1 255.255.255.255
!
interface Loopback55
ip address 192.168.39.1 255.255.255.255
!
interface Loopback56
ip address 192.168.45.1 255.255.255.255
!
interface Loopback57
ip address 192.168.100.1 255.255.255.255
!
interface Loopback58
ip address 192.168.99.1 255.255.255.255
!
interface Loopback59
ip address 192.168.98.1 255.255.255.255
!
interface Loopback60
ip address 192.168.97.1 255.255.255.255
!
interface Ethernet0
ip address 192.168.1.21 255.255.255.252
no ip mroute-cache
!
interface Serial0
ip address 192.168.1.6 255.255.255.252
no ip mroute-cache
!
interface Serial1
no ip address
no ip mroute-cache
!
router ospf 1
redistribute connected subnets
redistribute static subnets
network 192.168.1.4 0.0.0.3 area 2
!
router bgp 65000
no synchronization
bgp dampening
neighbor ibgp-peer peer-group
neighbor ibgp-peer remote-as 65000
neighbor ibgp-peer update-source Loopback0
neighbor ibgp-peer next-hop-self
neighbor ibgp-peer send-community
neighbor 192.168.0.1 peer-group ibgp-peer
neighbor 192.168.1.22 remote-as 65500
neighbor 192.168.1.22 send-community
default-metric 20
!
ip classless
!
!
line con 0
line aux 0
line vty 0 4
password cisco
login
!
end
Router3#exit
[Connection to 192.168.1.6 closed by foreign host]
Router2#exit
[Connection to 192.168.1.1 closed by foreign host]
Router1#exit
Connection closed by foreign host.
[wniaz@saranac wniaz]$ exit
logout
References:
- Internetworking with TCP/IP Vol.
II by Douglas
E. Comer
- Routing TCP/IP, Volume II (CCIE Professional
Development)
by Jeff Doyle, Jennifer DeHaven Carroll
- Cisco OSPF Command and Configuration
Handbook by William R.
Phd Parkhurst
- Ip Routing: Border Gateway Protocol (BGP) by Cisco
Systems Inc.
- EIGRP for IP: Basic Operation and Configuration
by
Alvaro Retana, et al
- RFC’s 1180, 1389, 1583, 1771.