This is the UDP port number the SNMP agent listens on for standard SNMP requests, defaulting to 161. An admin would only change this from the standard 161 in an unusual environment, such as a port conflict, and doing so means every management station must be reconfigured to query this node on the new port or polling will simply time out. For example, changing this to 1161 without updating the NMS's polling configuration would make this node silently stop responding to SNMP gets on port 161.