Devil's Advocate - Segment Routing, Why?

Mark Tinka mark.tinka at
Sun Jun 21 20:57:56 UTC 2020

On 21/Jun/20 22:21, Robert Raszuk wrote:

> Well this is true for one company :) Name starts with j .... 
> Other company name starting with c - at least some time back by
> default allocated labels for all routes in the RIB either connected or
> static or sourced from IGP. Sure you could always limit that with a
> knob if desired.

Juniper allocates labels to the Loopback only.

Cisco allocates labels to all IGP and interface routes.

Neither allocate labels to BGP routes for the global table.

> The issue with allocating labels only for BGP next hops is that your
> IP/MPLS LFA breaks (or more directly is not possible) as you do not
> have a label to PQ node upon failure.  Hint: PQ node is not even
> running BGP :).

Wouldn't T-LDP fix this, since LDP LFA is a targeted session?

Need to test.

> Sure selective folks still count of "IGP Convergence" to restore
> connectivity. But I hope those will move to much faster connectivity
> restoration techniques soon.

We are happy :-).

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