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