BESS WG:

We recently made some changes to the Packet Walk-Through for BGP SDWAN usage 
https://datatracker.ietf.org/doc/draft-ietf-bess-bgp-sdwan-usage/ .
Since the draft is already a WG draft, want to solicit feedback from the WG if 
the changes are appropriate.

5.1 Packet Walk-Through for Scenario #1 (Homogeneous WAN)
(This is referring to a type of SDWAN network with edge nodes encrypting all 
traffic over WAN to other edge nodes, regardless of whether the underlay is 
private or public.).

A single IPsec security association (SA) protects data in one direction. Under 
the Scenario #1, two SAs must be present to secure traffic in both directions 
between any two end points, which can be two C-PE nodes, two client ports, or 
two prefixes.
Upon power up, a SDWAN node can learn client routes from the Client facing 
ports in the same way as EVPN described in RFC8388. Controller, i.e. BGP-RR, 
facilitates the IPsec SA establishment and rekey management as described in 
[SECURE-EVPN]. Controller manages how client's routes are associated with 
individual IPSec SA.
Using Figure 2 of the Section 3.2 as an example. Let's assume that the IPsec 
SAs terminate at the C-PE nodes. To enable full mesh communication within 
client CN2 that are attached to C-PE1, C-PE3, and C-PE4, six one directional 
IPsec SAs must be established: C-PE1 <-> C-PE3; C-PE1 <-> C-PE4; C-PE3 <-> 
C-PE4. The C-PE node address (or loopback address) acts as the Next Hop address 
for the prefixes attached to the C-PE node.
When a C-PE receives a packet from its client port, the C-PE uses the IPsec SA 
whose destination address matches the Next Hop address of the packet's 
destination to encrypt the packet and forward the encrypted packet to the 
target C-PE via one of the C-PE's WAN ports.
When a C-PE receives an encrypted packet from its WAN port, it decrypted the 
packet and forward the inner packet to the client port based on the inner 
packet's destination address.

Any issues with this description?

Thanks, Linda Dunbar
_______________________________________________
BESS mailing list
[email protected]
https://www.ietf.org/mailman/listinfo/bess

Reply via email to