The BGP Attribute Filter feature enables BGP speakers to take a certain action based on the presence of a specified path attribute inside the UPDATE message received from a neighbor. Basically, there are two actions which a BGP speaker can take. When the update is...
Full iBGP Mesh and Route Reflection To avoid loops in a Full iBGP Mesh, BGP routers are only allowed to learn prefixes over iBGP from the router that advertises them or, alternatively, learn them via eBGP. In such cases, all BGP speakers within a single AS must be...
Network Address Translation (NAT) was originally described in RFC 1631. Although initially presented as a short term solution for preventing the IPv4 addresses depletion, it is still being used. What is so special about NAT that makes network engineers use it for more...
The BGP advertisement of a prefix with new attributes replaces the previous announcement of that prefix. This behavior is known as an Implicit Withdraw, which effectively prevents the advertisement of multiple paths for the same prefix. The RFC7911 discusses a BGP...
In this blog post, we will take a look at Kevin Myers’s presentation where he discusses deployment of both OSPF and BGP routing protocols in order to select optimal paths in a WISP (Wireless Internet Service Provider) network. WISP is an Internet Service...
