User guide

Layer 2 Switching in the Network Overview
2-1
iMG/RG Software Reference Manual (Switching)
2. Switching
2.1 Overview
2.1.1 Layer 2 Switching in the Network
The System consists of a Layer 2 switch coupled to a Network Processor. The aggregate is viewable as a single
Layer 2 switch, but this functionality is spread across the two devices - switch and the bridge - with interconnec-
tivity being provided by the CPU port.
Rate Limiting, QOS - and VLAN Tag management is provided at the edge of the system - via port configura-
tion.
By default - all traffic flows in one single VLAN - however an extension to this model is to use VLANs to segre-
gate traffic flows to certain ports.
2.1.2 Documentation Structure
The Preface listed all of the iMG/RG/iBG devices and to which product category they belong. Keeping this in
mind, the user can better use the remainder of this section, which is organized as follows:
• An overview of an area and its main attributes.
• The functions within an area. These are explained in some detail, usually with accompanying figures.
• A table that lists these functions and to which product category they apply. Notes help the user understand
why a function may or may not be relevant.
• A table that lists the commands and to which product category they apply.
• A command reference for each command and its parameters.
Note: The command reference subsection is generic for all product categories. The user should refer
to the the function and command tables to see how a command or parameter applies to a
specific product.
2.2 Switching
2.2.1 Overview
The iMG/RG/iBG product includes an integrated layer 2 managed switch providing Fast Ethernet transceivers
supporting 10Base-T, 100Base-TX and 1000Base-TX modes, high performance memory bandwidth (wire speed)
and an extensive feature set including Rate Limiting, QoS priority, VLAN tagging and MIB counters.