Why Does BGP Need Link State?

To educate us on what BGP-LS is and why it exists, the Packet Pushers' Heavy Networking podcast welcome Hannes Gredler. He’s heavily involved in the deepest corners of the networking industry as the CTO and founder of startup RtBrick, offering cloud-native routing software for telcos. He’s also chaired the IETF IS-IS working group, and was a Distinguished Engineer at Juniper Networks. He holds some routing patents. He’s a published author.Hannes knows what’s going on when it comes to BGP-LS, and volunteered to share some of his time with Heavy Networking.
We discuss:
- What BGP-LS is and the problems it solves
- How BGP-LS was conceived
- Why carry link state in BGP?
- Are we stuffing too many features into BGP?
- How BGP-LS compares to segment routing
- More
This is the video version of Heavy Networking 553: Why Does BGP Need Link State? You can listen to the audio episode here: packetpushers.net/podcast/hea...
Heavy Networking is part of the Packet Pushers network of technical podcasts, including Day Two Cloud, IPv6 Buzz, Full Stack Journey, and Network Break. Find them all at packetpushers.net

[@OrhanErgunCCDE]

After minutes 37, what Ethan and Hannes talks about is a separate protocol you can say. It is called BGP +SPF, discussed in IETF LSVR WG now, I discussed it with Keyur Patel and Jeff Tantsura here : czcams.com/video/llpFFNMS3fc/video.html , other than that BGP -LS and BGP + SPF is solving specific things.
One is carrying topology through the message bus that you can do many things on top, another is for the Hyperscalers mostly which provides topology and reliability and centralized override.
Different requirements, different solutions , and each of them has alternatives. In BGP - LS case, IGP extension is not quite a problem , assuming you have decent OSPF/IS-IS implementation , in BGP +SPF case, Link State IGPs again is an alternative , and proven to work under scale but RFC 7938 , RIFT , Openfabric etc, are some other alternatives...
Those who want to learn more about RIFT also, I discussed it with Tony P here : czcams.com/video/Q9cHVpM64LE/video.html