[c-nsp] Seamless MPLS interacting with flat LDP domains

[James Bensley]

On 6 May 2019 10:12:25 BST, adamv0025 at netconsultings.com wrote:
>> Robert Raszuk
>> Sent: Friday, May 3, 2019 3:16 AM
>> 
>> Radu,
>> 
>> The MPLS in modern DC is none starter purely from technology pov.
>> 
>> In modern DCs compute nodes are your tenant PEs all talking to rest
>of the
>> fabric L3. So if you want to roll MPLS you would need to do that to
>the
>> compute nodes. That means that with exact match you will see in MSDCs
>> millions of FECs and millions of underlay routes which you can not
>> summarize. Plus on top of that an overlay say L3VPNs for the
>tenant/pods
>> reachability.
>> 
>Well I guess whenever the summarization is used in the pure IP
>underlay, in
>MPLS underlay a seamless MPLS boundary would be used so all the
>underlay
>routes/FECs would then be contained only to compute nodes. 

DoD label allocations and longest-prefix matching for FECs means that summarization can be used in the a Seamless MPLS architecture:

https://tools.ietf.org/html/rfc5283
https://tools.ietf.org/html/rfc7032

Cheers,
James.