Port 153
SGMP
_Simple Gateway Monitoring Protocol (SGMP) is an early network protocol designed to manage and monitor network gateways. It was a precursor to SNMP and enabled administrators to gather gateway status and control traffic-related parameters, providing basic insights into network health and performance._.
Technical Details
Simple Gateway Monitoring Protocol (SGMP) is a legacy protocol developed in the 1980s to facilitate simple management functions for network gateway devices such as routers. SGMP operates primarily over UDP port 153 and enables basic querying and configuration tasks related to network devices in an IP network environment.
SGMP allowed management systems to retrieve or modify status variables associated with gateways, such as interface status, throughput statistics, error counts, or uptime. The protocol employed simple command types such as GET and SET, using plaintext message exchanges to carry management data. Its simplicity provided a lightweight control plane suitable for early networks with limited resources.
Due to its limitations—including a lack of extensibility, rudimentary security, and minimal feature support—SGMP was superseded by the Simple Network Management Protocol (SNMP) which expanded functionality, standardized Management Information Bases (MIBs), and introduced improved transport and security mechanisms. Today, SGMP is largely obsolete, rarely deployed, and primarily encountered in historical network studies or legacy device support scenarios.