Why is the Feasibility Condition Less Than?

7 May 2018 | 1 Comment

A reader recently emailed me with this question: Why isn’t the condition for a Feasible Successor set to less than (B. D will immediately reroute to the FS, which is C, without changing the FC. This works, because C’s cost to 100::/64 via D is 4, much higher than it’s cost to 100::64 along C->A.…

The EIGRP SIA Incident: Positive Feedback Failure in the Wild

9 April 2018 | Comments Off on The EIGRP SIA Incident: Positive Feedback Failure in the Wild

Reading a paper to build a research post from (yes, I’ll write about the paper in question in a later post!) jogged my memory about an old case that perfectly illustrated the concept of a positive feedback loop leading to a failure. We describe positive feedback loops in Computer Networking Problems and Solutions, and in…

On the ‘web: All you ever wanted to know about EIGRP

13 June 2017 | Comments Off on On the ‘web: All you ever wanted to know about EIGRP

In episode 5 the Network Collective panel dives deep into the inner-workings of EIGRP and how to tune the protocol to work best for you. This isn’t your run of the mill EIGRP training session though, so buckle up and dig in to learn a lot about a protocol which appears pretty straight forward on…