renghardt
commented
5 years ago Replies to the e-mails:
To [Med39]: "[Med] OK, but still don't see the need to have such assertion included. "
To [Med42]: "[Med] The administrative entity is the network operator of that AS.
[TE] Right. We may need a different word here."
Then my suggestion: "[TE] But yes, maybe we could have the administrative domain be a property instead?
[Med] That would make sense. For example, an application can decide to select a path that does not cross a given AS or better, an application can indicate a hint to an upstream network to avoid forwarding data via paths including a given AS.
[TE] Yes, that's the primary use case we had in mind, so we'll make sure it's supported."
He also linked to some other type of domains (?):
"The same considerations would apply for application-specific domains such as ITADs (IP telephony administrative domains, https://www.iana.org/assignments/trip-parameters/trip-parameters.xml#trip-parameters-5). "
On "Typically, backbone properties are less accessible to a host than domain properties, due to the potential increased distance and the lack of pre-existing trust or contractual relationship." [Med39]: Not sure about this. Not sure if "typically" is the right word here either, but, similar to the part with [Med33], the intention is to say that this might be the case.
On "hosts are less likely to be able to influence which path elements form their path in the backbone, as well as their properties." [Med40]: This may contradict with slicing use cases. Sounds interesting. Could you point me to a specific reference, please?
On "Presence of a certain [CROSSED: network] service function on the path": [Med41]: To be aligned with RFC7665 Agreed.
On "Administrative Entity: The administrative entity, e.g., the AS, to which a path element or subpath belongs." [Med42]: This is an administrative domain, not entity Isn't an AS also an entity? But yes, maybe we could have the administrative domain be a property instead?
On "Disjointness": [Med43]: you may also refer to the PCE RFCs which defines also the notion of near disjointness I found RFC 4655 saying "The path computation request may include a significant set of requirements, including the following: […] the number of disjoint paths required and whether near-disjoint paths are acceptable", but it does not define what near-disjoint is. Is there a specific degree of disjointness that is generally still considered "near"? Anyways, I think if a host or other entity knows about the degree of disjointness, it can decide whether this is "disjoint" enough. Maybe we want to add a reference to PCE as an example use case.