How to Configuring Routing Protocols

Function of routing protocol services: let the router knows how to get near to them and their respective networks. There are two basic types of routing protocols: distance vector and link state agreements.

Most simply could be the classification as a distance vector Protocol. They made their routing decisions based on the number of intermediate routers along a given path. The advantages given to very few resources, but has the following disadvantages: does not take into account of the available link bandwidth, or load. When there are long distances, they are restricted. Path may be valid, but because Gao Yue points, router decided to the remote host or the network is unavailable. In addition, these types of agreements in the default time interval is typically broadcast their entire routing tables. This can take a considerable amount of time and consume a lot of bandwidth. RIP, routing and BGP protocols belonging to this category.

By maintaining a database, they have received from other routers advertising link state protocols called link state database. This means that each router is fully accountable to the given location to determine the best path, from its point of view and alternate paths that already had such an idea, and if so, should the first path is not available.

Configuring RIP:

Routing Information Protocol (RIP) routing protocol is perhaps the most simple. Its role through broadcasts its entire routing table to all those involved in the network once every 60 seconds the IP or IPX once every 90 seconds. Hear a route from a remote router, this metric is increased by 1. This number cannot exceed 15. Pointer: 16 description cannot access network.

The simplicity of this Protocol refers to very small router must do each update. This allows the processor to perform other tasks. At the same time, there is no database maintenance. It's all contained in the routing table. This simple yet of the need to increase bandwidth, because the complete routing table must be sent over the network. In a large network, this can take quite a long time. In addition, it was not uncommon to separate network to more than 15 hops. The end node cannot communicate because metrics beyond "unreachable".

Configuration is a 3 step process. First, create a RIP process and determine whether or not to distribute its courses that any other routing process (such as routing or OSPF). Second, specify which networks will receive RIP announcements. Third, configure any address of the neighbor.

A sample configuration might look like

router rip
  redistribute igrp 1000
  network 2.3.4.0
  network 4.5.3.0
  neighbor 4.5.5.2
  neighbor 4.5.5.3

Configuring IGRP:

Configuring IGRPInterior Gateway Routing protocols (routed) is designed by Cisco systems in the mid 1980 of the 20th century the dynamic distance vector routing protocols. More than the maximum diameter of RIP routing advantages include network. Network exceeds 15 hops will not be available for access control in RIP networks. Routing allows 100 per cent jump, by default, you can set up to accept the path to 255 hops away.

We use user-configurable metrics including Internet latency, bandwidth, reliability, and load combinations. RIP, different routing routing is shared by its costs, provide cost equal or not equal to the load balance up to 4 paths to a given destination. Can be specified using variance factor equal or not equal cost. Path to determine how inequality of variance can perform load balancing. 1 (default) specified variance of load balancing only when all paths are of equal cost. With the "traffic-sharing" command, you can override this behavior. To allow only at the lowest cost to use the path, specify "traffic share min". "Traffic share balance" is the default.

Basic routing configuration is very similar to RIP. Routing routing on the router must create and participate in the network list. Number of optional routes also autonomous system. When running on a non-broadcast network routing, you can use the "neighborhood" commands, RIP a single entry system, will receive updates. Interfaces should not be involved in the specified address range (for example, if the interface is via some other Protocol (such as management of OSPF) routed network statement, it can specify passive "passive interfaces" statement.

 Example configuration:

router igrp 1000
 variance 3
 network 203.4.22.0
 network 204.103.24.0
 neighbor 204.103.24.5
 neighbor 204.103.24.6
 neighbor 204.103.24.7
 passive-interface Ethernet4/1
 passive-interface Fddi3/0

Configuring Enhanced IGRP: 

Enhanced route is a route redesigned by Cisco. When it became apparent in order to overcome some of the route is placed in a large number of restrictions on its use. Is mainly focused in the improvement measures. To this end, a new kind of convergence algorithm, introduced the double (dispersion update algorithm). Gained a new algorithm is one of the advantages of EIGRP loop-free routing table where assurance of control protocols. EIGRP also introduces some updates. This small number allowed to route messages, in turn, uses less bandwidth, leaving free for user data path of the data exchanged between routers. Partial update also allows the receiving router to spend less time to recalculate the routing table, because the course is not included in the update, have not been recalculated.

EIGRP two key features are support for variable-length subnet masks and any summary of the course. These allow support for CIDR routes, reducing the size of the entire routing table, and allows you to more easily maintainable routing table "classfull" routes are removed. When EIGRP is able to automatically summarize into a common route of possible routes. You can specify "No auto-summary" to disable this feature in the EIGRP configuration. Summary of the router that is configured on a per-interface basis to perform additional, "summary of IP address EIGRP" statements in advertising for a particular aggregation as belonging to a given autonomous system, as shown in the following interface configuration command.


 interface Ethernet0
    ip summary-address eigrp 1234 201.200.8.0 255.255.224.0
The results of this command are, ad 201.200.8.0 network block is reduced to aggregations of individual ads. So instead of sending 32 class c network routing, RIP, covering all 32 network a single ad instead.

Hello message exchange another add to EIGRP is supported. When EIGRP process starts, the router sends hello datagram using the multicast datagram on all those involved in the interface at the appropriate time. Once the router determines that the other router is participating in EIGRP, you can begin the process of exchanging updates. This allows the router to quickly determine a new router is added to the network, or when an existing router is inaccessible.