EIGRP is a Cisco proprietary protocol which means it will work only on Cisco routers. EIGRP is also called advanced distance vector or Hybrid routing protocol. Multicast or unicast is used for exchange of information. Multiple network layer protocols are supported. 100% loop-free. By default,EIGRP will limit itself to use no more than 50% of [...]
Yes the Enhanced Interior Gateway Routing Protocol (EIGRP) supports secondary addresses. However, because EIGRP supply data packets from the primary address, all the routers should be configured with the primary addresses that belong on the same subnet. Be sure that the primary address on the interface is configured for EIGRP by issuing the network command [...]
By default EIGRP limits itself to using no more than 50% of the interface bandwidth. Although, this is not very significance on high speeds like on Ethernet, it becomes critical on low speed links, especially on Nonbroadcast Multiaccess Address (NBMA) networks like Frame Relay. If the interface bandwidth configuration cannot be changed because of routing [...]
Usually passive interface command is used in routing protocols to accept information from neighbors but prevent it from sending information to neighbors But in case of EIGRP (Enhanced Interior Gateway Routing Protocol) it is exactly opposite.EIGRP discovers neighbours using the hello packets,before accepting routes and installing them in the routing table. Hello messages are usually [...]
In order to prevent Enhanced Interior Gateway Routing Protocol (EIGRP) updates from overwhelming the interface, Cisco IOS provides controls how much bandwidth it can consume on the physical interface. By default, EIGRP limits itself to using no more than 50 percent of the interface bandwidth. Although, this is not very significance on high speeds like [...]
EIGRP can utilize 5 separate metrics to determine the best route to a destination: Bandwidth (K1) Load (K2 Delay of the Line (K3 Reliability (K4) MTU (K5) By default, only Bandwidth and Delay of the Line are used
EIGRP uses AS (Autonomous system) number ranging from 1-65535 to identify collection of routers that share same information. EIGRP have less convergent time and is more efficient EIGRP supports both auto and manual route summarization Supports multiple routed protocols like IP ,IPX and apple talks EIGRP converges rapidly in the event of link failure EIGRP [...]
EIGRP uses non-periodic incremental routing updates. That is, EIGRP only sends routing updates about paths that have changed when those paths change. The basic problem with sending only routing updates is that you may not know when a path through a neighboring router is no longer available. You can not time out routes, expecting to [...]
DUAL (Diffusing Update ALgorithm) is the algorithm used by Cisco’s EIGRP routing protocol to ensure that a given route is recalculated globally whenever it might cause a routing loop
EIGRP will use six different packet types when communicating with its neighboring EIGRP routeres Hello Packets – EIGRP sends Hello packets once it has been enabled on a router for a particular network. These messages are used to identify neighbors and once identified, serve or function as a keepalive mechanism between neighboring devices. EIGRP Hello [...]
If the successor path is lost & there is no feasible successor path is available, router sends out query messages on all EIGRP enable interfaces & tries to find out an alternative path to the network. It is active state for that route.Now Router is waiting for reply from its neighbors. If reply is missing [...]
EIGRP sends hello packets every 5 seconds on high bandwidth links and every 60 seconds on low bandwidth multipoint links. -5-second hello: broadcast media, such as Ethernet, Token Ring, and FDDI point-to-point serial links, such as PPP or HDLC leased circuits, Frame Relay point-to-point subinterfaces, and ATM point-to-point subinterface high bandwidth (greater than T1) multipoint [...]
You can set the bandwidth value of an interface using the BANDWIDTH command.
The term successor can be defined as “one thing that succeeds another.” In IP routing, this simply refers to the next-hop of the best route. A feasible successor, therefore, is not our current best route, but one which could be used in the event our successor route disappears.
Successor is the neighbouring router with the best cost path too a destination network, will be marked as the successor for that network and will be used as the next hop to forward traffic to it.
A router discovers a neighbor when it receives its first hello packet on a directly connected network. The router requests DUAL to send a full route update to the new neighbor. In response, the neighbor sends its full route update. Thus, a new neighbor relationship is established in the following steps: When a router A [...]
There are 5 types of packets in EIGRP -Hello -Update -Query -Reply -ACK (Acknowledgement) Hello packets are used for neighbor discovery. As soon as you send hello packets and receive them your EIGRP routers will try to form the neighbor adjacency. Update packets have routing information and are sent reliable to whatever router that requires [...]
Neighbour, a neighbour is a router that can be reached through a network segment that is running the same EIGRP AS and is directly sharing routing information with the local router.