---
type: SNMP Concept
title: "SNMP Community String: What It Is & How to Secure It"
description: "What community strings are, RO vs RW, public/private defaults, and how to harden or move to SNMPv3."
resource: "https://snmp-monitoring.info/what-is-snmp/community-string/"
tags: [what-is-snmp]
timestamp: 2026-07-10T00:00:00Z
---

# SNMP Community String: What It Is & How to Secure It

What community strings are, RO vs RW, public/private defaults, and how to harden or move to SNMPv3.

## Related concepts

- Up: [What Is SNMP? Simple Network Management Protocol Explained](/what-is-snmp/index.md)

## Frequently asked questions

### What is an SNMP community string?

A plaintext shared secret used by SNMPv1/v2c so the agent can accept or reject a manager's requests. Functionally a password, without modern password protections on the wire.

### What is the default community string?

Conventionally public for read-only and private for read-write. Both must be changed; scanners try them first.

### Is the community string encrypted?

No. In v1/v2c it is sent in cleartext over UDP. SNMPv3 is the path to authenticated/encrypted sessions (when configured with priv).

### RO vs RW community—what's the difference?

RO allows reads (Gets/walks) per the view. RW also allows Sets. Monitoring almost always needs RO only; leave RW off unless you have a specific write use case.

## Source

Concept generated from https://snmp-monitoring.info/what-is-snmp/community-string/ — the SNMP Monitoring vendor-neutral knowledge base. Content is limited to what that page states (no external claims added here).