3.1.3.3.1 Delay Use of Protocol Sequences on the Endpoint Mapper
On a system that supports a given protocol sequence, these extensions explicitly allow an endpoint mapper instance to delay listening on that protocol sequence until at least one server using dynamic endpoints on the system is listening on that protocol sequence.
Even though a system is fully capable of using a protocol sequence, it MAY choose not to listen on a particular protocol sequence when no server is using it. Therefore, a client implementation of these extensions MUST NOT assume that a system that is not listening on a particular protocol sequence is necessarily incapable of supporting that protocol sequence.<71>