How to Select a Network Switch
The network switch is the most common network device implemented with company
infrastructure and as such the selection of any new switches or upgrading is a key part of
most network design projects. The Cisco network switch components include Switch Chassis,
Supervisor Engine, Switching Modules, IOS/CatOS software and Power Supplies.
The decision to buy new switches or upgrade equipment will be decided after
considering the network assessment and design features specified. Wireless designs,
as an example, will have network switches interfacing with access points. That will
have an affect on the switch such as increased utilization, assigned switch ports,
access control lists, Trunking, Spanning Tree Protocol and increased wattage draw
from Power over Ethernet (PoE).
Switch Chassis Features
The Switch Chassis features include - chassis dimensions, number of slots, processor
slot assignments, switching fabric, engines types supported, power supplies, rack units needed.
Cisco Supervisor Engine (SE) Features
Cisco switches are implemented with an Engine (Switch Processor) for processing packets
on a network segment. Routing is accomplished with an on-board Multi Layer Switch Feature
Card (MSFC) or Route Processor running IOS code. The switch Engine running IOS code on the
MSFC and the switch processor is in native mode, while those running CatOS on the
processor are in hybrid mode.
Some engines won't support native and hybrid mode. The engine with no MSFC supports what
is called CatOS mode. Select the engine that matches your design specifications. The MSFC
module is integrated with the Engine or upgradeable. You must implement a PFC module with
any MSFC. Some Engines have no MSFC module - the routing is integrated with the hardware
and as such support native mode only.
The Cisco Supervisor Engine features include - supported chassis, uplink speed,
processor memory, native IOS, CatOS, PFC, MSFC, slot assignment, failover.
These are some of the popular Cisco engines and their switching features.
720 - Cisco 6500 switches, 400 mpps, MSFC3, IOS, CatOS
32 - Cisco 6500 switches, 15 mpps, MSFC2A, IOS, CatOS
V - Cisco 4500 switches, 72 mpps, Integrated Routing, IOS
IV - Cisco 4500 switches, 48 mpps, Integrated Routing, IOS