Loop detection rewording

[fiestajetsam]

Ulrich suggests:

Isn't it preferable to use positive requirements instead of negative ones? For example: Instead of " The protocol's loop avoidance mechanisms SHOULD NOT use identifiers tied to network topology." Why not " The protocol's loop avoidance mechanisms SHOULD be able to use identifiers that change over time. "?

I'd propose rewording it to:

The protocol's loop avoidance mechanisms MUST be able to use identifiers that change over time and are not tied to network topology

[fiestajetsam]

cc @davidv1992 as this touches your contributions and I suspect you'll have opinions about the text I've proposed in 3cd72f231b4aad3.

[davidv1992]

I see no problems in the new wording.

[fiestajetsam]

Thanks!