he performance of the MSC components over time: the main processor, circuit switching, speech coders, and packet data. Congestion in any these areas should be addressed by the wireless system planners before it affects the quality of system service. 39.7 Signaling Capacity Signaling congestion can do major damage to system performance. ANSI-41 signaling over the SS7 network is a critical part of every registration, every call, and every other subscriber service in the wireless system. For this reason, SS7 procedures tell us to keep utilization of its fully redundant facilities below 40 percent. All SS7 links in the wireless system should be monitored closely for traffic levels at all times of the day. This includes all the A links from signal transport points (STPs) to MSCs, home location registers (HLRs), visitor location registers (VLRs), short message service centers (SMSCs), and service control point (SCP) databases. It also includes F links that carry signaling messages directly from one MSC to another. There may be a chance to watch the other links in the SS7 network as well. These links should stay less than half full all the time. The SS7 rules say that we cannot go above 40 percent, so any occupancy over half is a warning sign that things are getting congested in the ANSI-41 signaling network. We should be watching as much of the SS7 network as we can get reports for. Any SS7 link in our wireless signaling network reaching 50 percent of its capacity should send up a red flag for us. Either it is getting too full of ANSI-41 messages, which is a capacity engineering concern, or its redundant SS7 link is down, which is a maintenance concern. In either case, we should respond when a signaling facility is half full. The dual SS7 links also should stay balanced. If we see more than two-thirds of the traffic on one link, then we should investigate to see why the signaling traffic is staying balanced. Transport Utilization and Congestion Transport should not be a limiting factor in wireless telephone system perf