Snmp - EnGenius EWS Series User Manual

SNMP

Simple Network Management Protocol (SNMP) is an application layer protocol designed specifically for
managing and monitoring network devices. Simple Network Management Protocol (SNMP) is a popular
protocol for network management. It is used for collecting information from and configuring network
devices such as; servers, printers, hubs, Switches, and routers on an Internet Protocol (IP) network.
SNMP is used to exchange management information between a network management system (NMS)
and a network device. A manager station can manage and monitor the Switch through their network via
SNMPv1, v2c and v3. An SNMP managed network consists of two components; agents and a manager.
An agent translates the local management information from the managed Switch into a form that is
compatible with SNMP. SNMP allows a manager and agents to communicate with each other for the
purpose of accessing Management Information Bases (MIBs). SNMP uses an extensible design, where
the available information is defined by MIBs. MIBs describe the structure of the management data of a
device subsystem; they use a hierarchical namespace containing Object Identifiers (OID). Each OID
identifies a variable that can be read or set via SNMP.
The manager is the console through which network administrators perform network management
functions.
Several versions of SNMP are supported. They are v1, v2c, and v3. SNMPv1, which is defined in RFC 1157
"A Simple Network Management Protocol (SNMP)", is a standard that defines how communication
occurs between SNMP-capable devices and specifies the SNMP message types. Version 1 is the simplest
and most basic of versions. There may be times where it's required to support older hardware. SNMPv2c,
which is defined in RFC 1901 "Introduction to Community-Based SNMPv2", RFC 1905, "Protocol
Operations for Version 2 of the Simple Network Management Protocol (SNMPv2)", and RFC 1906
"Transport Mappings for Version 2 of the Simple Network Management Protocol (SNMPv2)". SNMPv2c
updates protocol operations by introducing a GetBulk request and authentication based on community
names. Version 2c adds several enhancements to the protocol, such as support for "Informs". Because of
this, v2c has become the most widely used version. Unfortunately, a major weakness of v1 and v2c is
security. To combat this, SNMP v3 adds a security features that overcome the weaknesses in v1 and v2c.
If possible, it is recommended that you use v3 — especially if you plan to transmit sensitive information
across unsecured links. However, the extra security feature makes configuration a little more complex.
In SNMPv3, User-based Security Model (USM) authentication is implemented along with encryption,
allowing you to configure a secure SNMP environment. The SNMPv3 protocol uses different terminology
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