why am i in this handbasket? (was Devil's Advocate - Segment Routing, Why?)

Sun Jun 21 11:31:47 UTC 2020

On 21/Jun/20 13:11, Masataka Ohta wrote:

>
> If information to create labels at or near sources to all the
> possible destinations is distributed in advance, may be.

But this is what happens today.

Whether you do it manually or use a label distribution protocol, FEC's
are pre-computed ahead of time.

What am I missing?

> But
> it is effectively flat routing, or, in extreme cases, flat host
> routing.

I still don't get it.

>
> Or, if information to create labels to all the active destinations
> is supplied on demand, it is flow driven.

What would the benefit of this be? Ingress and egress nodes don't come
and go. They are stuck in racks in data centres somewhere, and won't
disappear until a human wants them to. So why create labels on-demand if
a box to handle the traffic is already in place and actively working,
day-in, day-out?

Mark.