External BGP Controller for L3 Switch BGP routing

Mon Jan 16 13:48:11 UTC 2017

On Mon, Jan 16, 2017 at 01:36:54PM +0100, Tore Anderson wrote:
> 
> But here you're talking about the RTT of each individual link, right,
> not the RTT of the entire path through the Internet for any given flow?
> 
> Put it another way, my ??Internet facing?? interfaces are typically 10GEs with
> a few (kilo)metres of dark fibre that x-connects into my IP-transit providers'
> routers sitting in nearby rooms or racks (worst case somewhere else in
> the same metro area). Is there any reason why I should need deep
> buffers on those interfaces?a

It would be RTT of the entire path through the Internet where TCP establishes sessions.  Longer RTT, longer window, more burst.

So, yes you'll need deeper buffers for serving IP transit, regardless of the local link (router-to-router) latency.

For data centers, internal traffic within the DC is low latency end to end, so burst is relatively small.

James