Understanding How Oversubscribed Gigabit Ethernet Works - Cisco WS-C2948G-GE-TX Configuration Manual

Understanding How Gigabit Ethernet Works

Understanding How Oversubscribed Gigabit Ethernet Works

The Catalyst 4500 series Gigabit Ethernet modules provide a network-backbone connection for multiple
servers or high-end workstations. The following modules are supported:
•
•
•
•
•
On all modules, each uplink module port has 1-Gbps dedicated bandwidth. These ports typically connect
to the network backbone.
Table 5-4
Table 5-4
Module
WS-X4412-2GB-T
WS-X4418-GB
On all modules, the oversubscribed ports are segmented into groups of four ports each. Each group of
four ports shares 1 Gbps of bandwidth. The average bandwidth that clients and servers need to connect
to ports in the same group should not exceed 1 Gbps.
Table 5-5
Table 5-5
1, 2, 3, 4
Table 5-6
Table 5-6
Uplink Port 1
Table 5-7
Catalyst 4500 Series, Catalyst 2948G, Catalyst 2948G-GE-TX, and Catalyst 2980G Switches Software Configuration Guide—Release 8.2GLX
5-4
WS-X4412-2GB-T
This 1000BASE-T 14-port module provides 2 dedicated uplink module ports (GBIC) and
12 oversubscribed ports (possible blocking).
WS-X4418-GB
This 1000BASE-X 18-port module provides 2 dedicated uplink module ports (GBIC) and
16 oversubscribed ports (possible blocking).
WS-X4424-GB-RJ45
This 10/100/100BASE-TX module provides 24 oversubscribed ports (possible blocking).
WS-X4448-GB-RJ24
This 10/100/100BASE-TX module provides 48 oversubscribed ports (possible blocking).
WS-X4448-LX
This Gigabit Ethernet optical line terminator module provides 48 oversubscribed ports (possible
blocking).
lists the uplink module port IDs for each module.
Uplink Port Module IDs for Gigabit Ethernet Modules
shows how the oversubscribed ports are grouped for module WS-4412-2GB-TX.
Oversubscribed Port Groupings for Module WS-4412-2GB-TX
5, 6, 7, 8
shows how the oversubscribed ports are grouped for module WS-4418-2GB.
Oversubscribed Port Groupings for Module WS-4418-2GB
Uplink Port 2
shows how the oversubscribed ports are grouped for module WS-X4424-GB-RJ45.
Chapter 5
Port ID
13 14
1 2
9, 10, 11, 12 Uplink Ports
(13, 14)
3, 5, 7, 9 4, 6, 8, 10
Configuring Gigabit Ethernet Switching
11, 13, 15, 17 12, 14, 16, 18
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