General Functions For Redundant Ethernet Boards; Forwarding; Simple Network Management Protocol (Snmp) - GE MiCOM P40 Agile Technical Manual

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GENERAL FUNCTIONS FOR REDUNDANT ETHERNET BOARDS

The following functions apply to all redundant Ethernet protocols.
4.1

FORWARDING

The MiCOM Ethernet switch products support store and forward mode. The switch forwards messages with known
addresses to the appropriate port. The messages with unknown addresses, the broadcast messages and the
multicast messages are forwarded out to all ports except the source port. MiCOM switches do not forward error
packets, 802.3x pause frames, or local packets. 802.1p priority tagging is enabled on all ports.
4.2

SIMPLE NETWORK MANAGEMENT PROTOCOL (SNMP)

Simple Network Management Protocol (SNMP) is a network protocol designed to manage devices in an IP network.
SNMP uses a Management Information Base (MIB) that contains information about parameters to supervise. The
MIB format is a tree structure, with each node in the tree identified by a numerical Object Identifier (OID). Each OID
identifies a variable that can be read or set using SNMP with the appropriate software. The information in the MIB
is standardized.
Each system in a network (workstation, server, router, bridge, etc.) maintains a MIB that reflects the status of the
managed resources on that system, such as the version of the software running on the device, the IP address
assigned to a port or interface, the amount of free hard drive space, or the number of open files. The MIB does not
contain static data, but is instead an object-oriented, dynamic database that provides a logical collection of
managed object definitions. The MIB defines the data type of each managed object and describes the object.
The SNMP-related branches of the MIB tree are located in the internet branch, which contains two main types of
branches:
Public branches (mgmt=2), which are defined by the Internet Engineering Task Force (IETF).
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Private branches (private=4), which are assigned by the Internet Assigned Numbers Authority (IANA). These
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are defined by the companies and organizations to which these branches are assigned.
The following figure shows the structure of the SNMP MIB tree. There are no limits on the width and depth of the
MIB tree.
Px4x-REB-TM-EN-6
Chapter 5 - Operation
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