Apparatus, and associated method, for identifying radio network service availability

A method of operation of a mobile node capable of communications with a selected network of a plurality of networks, each of the plurality of networks broadcasting a network system information message on an associated channel in a geographic area, each network system information message including identification of at least one communication service supported by the broadcasting network of a plurality of communication services, comprising:

• maintaining in a channel listing identification of network-associated channels;
• monitoring a plurality of identified channels of said channel listing for the system information broadcast by networks on associated channels;
• detecting a system information message on a monitored channel from a one network of the plurality of networks;
• detecting values representative of the availability of a communication service from said detected system information message of said one network broadcasting on its associated channel;
• ascertaining from said detected values whether said one network supports a desired communication service;
• and
• permitting a subsequent selection of said one network and registration with said one network by the mobile node for communication of messages via said desired communication service when said one network is ascertained to support said desired communication service.