Anycast

[Suprit Chinchodikar]

Hello, 

Whay is Anycast and why do we need it?

Also, what is Anycast BGP? Does it work similiar like unicast vpnv4 bgp? and cant we use any IGP for example OSPF for anycast routing?

Thanks,

Suprit

[Mark Elsen]

 - FYI : https://www.noction.com/blog/bgp-anycast#:~:text=Anycast%20is%20a%20configuration%20method,0.0%20%E2%80%93%20239.255.

 M.

[Suprit Chinchodikar]

I already went to  https://www.noction.com/blog/bgp-anycast#:~:text=Anycast%20is%20a%20configuration%20method,0.0%20%E2%80%93%20239.255. but it does not make any sense to me.
Its say's " Packets to the anycast IP are routed through the shortest path to the server, reducing latency and improving service resiliency".

I can achieve the above statement using the bgp attributes as well like as_path prepend. Why we need anycast then.

Also how does bgp know that to which server to send the traffic as server's use same address in anycast routing as per my knowledge.