Border Gateway Protocol (BGP) in a nutshell
I have been busy writing some posts on some general topics for those readers who want some high-level overviews of various network terms and items. Border Gateway Protocol (BGP) is the core routing protocol used to exchange information about network …
The Mess we call BGP
Ever wonder why BGP seems to be such a complicated protocol to administer? It seems pretty straightforward to set up. Some commands, and you have a BGP session. Easy huh? BGP is one of those things where the more BGP …
A tool to find out if BGP is lying to you
APNIC has a bog article on detecting “bgp lies”. https://blog.apnic.net/2021/05/24/a-tool-to-detect-bgp-lies/Do you ever wonder whether you can really trust other networks, such as your provider(s) and peers? More precisely, wouldn’t you like to be able to tell if the traffic you send always …
Proper BGP DENY-ALL filter for mikrotik
This content is for Patreon subscribers of the j2 blog. Please consider becoming a Patreon subscriber for as little as $1 a month. This helps to provide higher quality content, more podcasts, and other goodies on this blog.To view this …
BGP, a single /24 and two diverse non-connected exit points
I am starting to see the following scenario more and more as IPv4 space is hard to get, but isn’t. With ARIN it is still possible to get an IPv4 allotment. Many smaller ISPs qualify for a /24 and can …
Mikrotik Connection tracking and CPU usage
This content is for Patreon subscribers of the j2 blog. Please consider becoming a Patreon subscriber for as little as $1 a month. This helps to provide higher quality content, more podcasts, and other goodies on this blog.To view this …
ARIN IRR Walkthrough
https://www.arin.net/announcements/20200728/ ARIN Internet Routing Registry walkthrough.
FD-IX: Local-pref and default routes
I just finished up an article over on the FD-IX blog about local-prefs, default routes, and Internet exchanges. https://www.fd-ix.com/uncategorized/local-pref-and-default-routes/ Not everyone on the Internet needs full feeds from their provider. In this case, how does learning routes from an Internet …
Hurricane Electric Route Filtering Algorithm
The following is from http://routing.he.net/algorithm.html . This outlines the criteria HE.NET uses for filtering routes from peers and customers. This is the route filtering algorithm for customers and peers that have explicit filtering: 1. Attempt to find an as-set to …