Subject: [bess] Erik Kline's Discuss on draft-ietf-bess-evpn-inter-subnet-forwarding-09: (with DISCUSS and COMMENT)

From: Erik Kline via Datatracker <[email-masked]>
Date: Tue, 14 Jul 2020 23:22:16 -0700

Erik Kline has entered the following ballot position for
draft-ietf-bess-evpn-inter-subnet-forwarding-09: Discuss

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DISCUSS:
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[ general ]

* Can you give an example of what happens to non-IPv4/IPv6 Ethernet packets
  received at the NVE/PE?  Do they get bridged, and if so how far?  What
  happens if a host in BT1 ARPs for IPv4 address associated with a TS in
  a different BT?

* Where there are multiple prefixes in an IP-VRF, is there a constraint that
  any other IP-VRF that contains one of the prefixes must contain all of them?
  Perhaps that's in 7432...?

[ sections 4, 5.4, 5.4, 6.3, 6.4, 9.1.2, 9.2.2 ]

* Please document what happens to IPv4 TTL/IPv6 Hop Limit values as they
  cross various NVEs/PEs.

[ section 7 ]

* Is there a reference for IRB-EXT-MOBILITY?

* The two statements:

  (1) "Although the language used in this section is for IPv4 ARP,
      it equally applies to IPv6 ND."

  (2) "If there is [a] many-to-one relationship such that there are many host
      IP addresses correspond[ing] to a single host MAC address ..., then to
      detect host mobility, the procedures in [IRB-EXT-MOBILITY] must be
      exercised..."

  are in direct conflict.  All IPv6 hosts having at least one non-link-local
  unicast address will have more than one IP address per MAC and this section,
  or even this document, would not apply?

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COMMENT:
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[ general ]

* I believe this is true, but can you just state here (not in the doc) that
  there are no multi-link subnets that can be created with this model as
  defined in RFC 4903? It seems like everything is as it should be, but just
  to double-check.

[ section 1 ]

* IP-VRF definition: s/VPN Routing.../Virtual Routing/?

[ section 3 ]

* 2nd to last paragraph: Is any of this still true for a setup that
  involves multiple IPv6 prefixes per BD, maybe I misunderstood
  (or maybe this assumed single prefix per broadcast domain w/ IPv4-only?).

  Perhaps avoid suggesting there's a 1:1 relationship and use phrases
  likes "at least as many X as there are Y" or something?

[ section 4 ]

* ARP table: a less IPv4-specific name, even though it's define to hold both
  IPv4 and IPv6 associations, would be "neighbor table".  That might be
  overloaded in routing contexts so no need to change it.