Transcript Introduction to networking

Introduction to networking
Dynamic routes
Objectives
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Define dynamic routing and its properties
Describe the classes of routing protocols
Describe the basic router configuration commands for
protocols
Dynamic routing overview
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Dynamic routing allow routers to learn about remote
networks fro mother routers and update their own routing
tables with new information
Dynamic routing is necessary to allow networks to update and
adapt quickly to changes
The success depends on the maintenance of a routing table
and timely distribution of knowledge
Dynamic routing depends on routing protocols which
describe:
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How to send updates
What knowledge is contained in these updates
When to send this knowledge
How to locate recipients of the updates
Administrative distance is used to determine the preferred
source of routing updates
Routing protocols
Identifying the classes of interior gateway
routing protocols
Determines direction, or vector
(exit interface), and Distance (metric)
to any link in the internetwork
Recreates the exact topology of the
entire internetnetwork
Distance vector
Each router receives a routing table from its directly connected neighbour routers.
The distance vector algorithm (Bellman-Ford) does not allow a router to know the
exact topology of an internetwork since each router only sees its neighbor routers.
Distance vector network discovery
The interface that leads to each directly connected network has a distance of 0
Distance vector network discovery
An analogy of distance vector could be the signs found at a highway intersection.
A sign points toward a destination and indicates the distance to the destination.
Further down the highway, another sign points toward the destination, but now the
distance is shorter. As long as the distance is shorter, the traffic is on the best path.
Link state routing protocol features
Consists of all
LSA’s
Link-state advertisement (LSA) - a small packet of routing information that is sent
between routers
Topological database - a collection of information gathered from LSAs
SPF algorithm - a calculation performed on the database that results in the SPF tree
Routing table - a list of the known paths and interfaces
Shortest path calculations
Link state topology changes
Link state concerns
Routing configuration
IP network number of directly connected network
GAD(config)#router rip
GAD(config-router)
#network 172.16.0.0
Configure EIGRP
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To configure EIGRP on a router
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router(config)#router eigrp autonomous-system
router(config)#router eigrp 1
An autonomous system is a collection of networks under
a common administrative control
EIGRP uses a autonomous system number, but calls this a
process ID
The process ID essentially refers to an instance of the
protocol running on a router
All the routers running in the same routing domain that
are using EIGRP must have the same process ID in order
to communicate
Configure EIGRP with a network
address
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router(config)#router eigrp 1
router(config)#network 172.16.0.0
Summary
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Dynamic routing scales better to larger, more complex
networks
They involve more complex protocols that demand a
greater knowledge of networking
Questions...
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...are there any?