In today's modern networks, fast convergence has become a mandatory requirement.
If we want to achieve fast convergence, each of the steps below need to be optimized
1. Failure Detection
2. Failure Propagation
3. Processing of new information
4. Updating RIB/FIB
1. Failure Detection:- "How long does it take me to detect a failure?"
This normally depends on the Hello/Hold down/Dead timers of the routing protocol. We can either tune these timers or use a mechanism such as "BFD" which we have seen in our earlier post.
2. Failure Propagation:- "How long does it take me to tell everyone else?"
In EIGRP, this is done through Query/Reply packets. We can reduce the Query domain by configuring the routers as "stub".
In OSPF, this depends on the area size and the LSA flooding procedure. We can tune the LSA timers to change this.
If we want to achieve fast convergence, each of the steps below need to be optimized
1. Failure Detection
2. Failure Propagation
3. Processing of new information
4. Updating RIB/FIB
This normally depends on the Hello/Hold down/Dead timers of the routing protocol. We can either tune these timers or use a mechanism such as "BFD" which we have seen in our earlier post.
2. Failure Propagation:- "How long does it take me to tell everyone else?"
In EIGRP, this is done through Query/Reply packets. We can reduce the Query domain by configuring the routers as "stub".
In OSPF, this depends on the area size and the LSA flooding procedure. We can tune the LSA timers to change this.
