ELI5: What is SNMP?
SNMP lets you check on your network devices from afar, like calling each room in a hotel to ask if everything is okay. The newest version adds a secret code so nobody can eavesdrop.
Definition
SNMP (Simple Network Management Protocol) is an internet protocol used to monitor, manage, and collect performance data from network devices such as routers, switches, firewalls, servers, and printers. It enables network management systems (NMS) to query device status, receive alerts (traps), and modify device configurations.
Key Details
- SNMPv1/v2c: use “community strings” as passwords; transmitted in cleartext — considered insecure
- SNMPv3: adds authentication (MD5/SHA) and privacy (DES/AES encryption) — use SNMPv3 exclusively for security
- SNMP traps are unsolicited alerts sent by devices to the management system when events occur
- SNMP runs on UDP port 161 (queries) and 162 (traps)
- Misconfigured SNMP with default community strings (“public,” “private”) is a common vulnerability
Connections
- Parent: network-monitoring — SNMP is a key protocol for network device monitoring
- See also: bandwidth-monitoring