liu haoran wrote on 13/05/2025 20:09:
A
child AS-SET must still have explicitly
defined members to ensure operational validity.
no, this isn't actually the case, which is why members: is optional.
Your position might be that this is beneficial for your members on the
basis of your policy, but that's a different issue. There's no reason in
the specification that an as-set can't be empty, even if your IXP might
have a different policy position on this.
The
2,000 AS-SETs lacking members highlight a significant data quality
issue. While technically compliant with RFC 2622, these empty AS-SETs
serve no practical purpose and may lead to routing policy management
challenges.
There may be valid operational reasons why an operator would want their
as-set to be empty, e.g. they might want a placeholder as-set in someone
else's routing policy which they can update as required. Or they might
want to use specific constructions like AS-NULL in their routing policy
for some reason.
Nick