3.1.3 Initialization

The first time the protocol is initialized, the server MUST create a unique instance GUID and SHOULD set its metadata version to zero. In subsequent initializations, the server SHOULD test whether its set of IP addresses has changed since the previous invocation by using the metadata version from the previous invocation if the set is unchanged or incrementing the metadata version if the set is different.<1> If the server does not test whether its set of IP addresses has changed, the server MUST create a new unique instance GUID.

The server MUST identify its WS-Discovery scopes by implementation-dependent means.<2>

The server MUST begin listening for messages. Transport information is specified in [WS-Discovery] section 2.4.