EIGRP (Enhanced Interior Gateway Routing Protocol)
Importance:
- Biggest advantage of EIGRP is backup route
- Simple in configuration
- Flexibility in Summarization
- Unequal Cost Load balancing advantage
- Combination of distance vector and link state protocol and Cisco call it Hybride protocol
- Support multiple Routing protocol
EIGRP Tables and Terminology:
EIGRP made three tables in database
- Neighbor Table
- Topology Table
- Routing Table
Terminology:
- Feasible distance (FD) (Total distance destination)
- Advertised distance (AD) (Total distance from source neighbor to distance)
- Successor (That is the primary path to reach the destination)
- Feasible Successor (That is the backup path of the destination)
- Active Route (Active when primary path is disable)
- Passive Route (Its mean that primary path is stable)
* To be considered a feasible successor, the AD must be less than thr FD of the successor
Verification Command:
R1#show ip eigrp toplogu
Visiting the Friendly EIGRP neighbor (EIGRP packet information)
- Hello: Create Relationship with the neighbor
- Update: Send updates (not complete routing table only send update)
- Query: Ask about Routes to neighbors
- Reply: Response to Query
- Ack: Acknowledge the update, Query and reply
Understand EIGRP metric Calculation:
What us metric? It means who good that is?
- Bandwidth
- Delay
- Reliability
- Loading
- MTU
Bandwidth and delay is statically and reliability, loading and MTU is dynamically configure and never get these in
Metric calculation:
Real (Default) = 256*(BW +`Delay)
BW = 10 ^ 7BW
Delay = Delay in Microseconds