Greg,
> On Apr 7, 2023, at 1:03 PM, Greg Mirsky <[email protected]> wrote: > Since the feature is intended to be used for single-hop, the source address > SHOULD be an address on the shared subnet with the interface of the device > that is looping the packets back. Perhaps it might even be reasonable to > require that the source and destination addresses are identical when possible? > GIM2>> As I understand RFC 5881 <https://www.rfc-editor.org/rfc/rfc5881>, > Section 4 recommends not to use an address on the same network as the > destination IP address, nor use a link-local IPv6 address as the source IP > address for an Echo message: > In particular, the source address SHOULD NOT be part of the subnet > bound to the interface over which the BFD Echo packet is being > transmitted, and it SHOULD NOT be an IPv6 link-local address, unless > it is known by other means that the remote system will not send > Redirects. > Do you think that the normative part of Section 4 is applicable to > draft-ietf-bfd-unaffiliated-echo? Fantastic reference and one I should have looked for. I believe you're correct and that this is an appropriate reference for the unaffiliated draft. One consideration that is interesting is what address is appropriate to configure when a system has exactly one interface? -- Jeff
