On 16 September 2020 23:51:03 CEST, Robert Raszuk <robert@raszuk.net> wrote:
Hi Ron,
If you want an IPv6 underlay for a network offering VPN services
And what's wrong again with MPLS over UDP to accomplish the very same with simplicity ?
MPLS - just a demux label to a VRF/CE UDP with IPv6 header plain and simple
+ minor benefit: you get all of this with zero change to shipping hardware and software ... Why do we need to go via decks of SRm6 slides and new wave of protocols extensions ???
Best, Robert.
Please consider the TE mechanism described in draft-bonica-6man-comp-rtg-hdr and the service labeling mechanism
in draft-bonica-6man-vpn-dest-opt. These can be deployed on a mix and match basis. For example can deploy:
- Draft-bonica-6man-vpn-dest-opt only, allowing traffic to follow
described the
least-cost path from PE to PE. - Deploy draft-bonica-6man-vpn-dest-opt only, using a legacy method (VXLAN, RFC 4797) to label services.
In all cases, the semantic of the IPv6 address is unchanged. There is no need to encode anything new in the IPv6 address.
MPLSoUDP lacks transport engineering features like explicit paths, FRR LFA and FRR rLFA, assuming only a single IP header is used for the transport abstraction [1]. If you want stuff like TI-LFA (I assume this is supported in SRm6 and SRv6, but I'm not familiar with these, sorry if that is a false assumption) you need additional transport headers or a stack of MPLS labels encapped in the UDP header and then you're back to square one. Cheers, James. [1] I'm interested to hear if anyone has done any large scale MPLSoUDP work. Did you hack in this functionality with static egress interface entries/static routes pushed from a central controller for specific IPs reserve as "path" IPs?