There has been a number of efforts to implement FIB (actually BGP RIB) compression. There’s a white paper from MS research; I recall Spotify talking of running off-box BGP compression SW and re-injecting summarized BGP RIB; Volta Networks had an implementation of full BGP table compression to about 370K routes with no connectivity loss and reasonably fast reaction of topology changes/disaggregation needed(it even won some Intel price for innovation), not sure what happened to it (Volta had been acquired by IBM some time ago). To my memory - IOS-XR allows off box custom best path logic and re-injection of routes into BGP RIB Cheers, Jeff
On Oct 10, 2022, at 09:26, William Herrin <bill@herrin.us> wrote:
On Mon, Oct 10, 2022 at 8:37 AM Mike Hammett <nanog@ics-il.net> wrote:
Feasibility of adding some middleware that culls unneeded routes (existing more specific and aggregate routes pointing to the same next hop), when that table starts to fill?
This is called "FIB aggregation." It exists and works but is not widely adopted.
Regards, Bill Herrin
-- For hire. https://bill.herrin.us/resume/