Question: Which SCCP class is utilized by the BSSAP+ protocol for signalling between the SGSN and VLR over the Gs interface?
Option 1: Class 0
Option 2: Class 1
Option 3: Class 2
Option 4: Class 3
Explanation: The BSSAP+ protocol, for the Gs interface between the Serving GPRS Support Node (SGSN) and Visitors Location Register (VLR), utilizes only SCCP Class 0 services. This class is chosen for its connectionless nature, suiting signalling requirements over the Gs interface within the same Public Land Mobile Network (PLMN).