Filter
Top Products
23-2
ATM Switch Router Software Configuration Guide
OL-7396-01
Chapter 23 Configuring the ATM Traffic-Shaping Carrier Module
About the ATM Traffic-Shaping Carrier Module
Note Traffic-shaping configurations do not apply to regular virtual path (VP) tunnels defined on that interface,
except in the case of unspecified bit rate (UBR) VP tunnels. For example, when best-effort traffic
shaping is enabled on a physical interface, all the UBR VP tunnels defined on that interface are shaped
to their peak cell rate (PCR), but individual VCs within those VP tunnels are not shaped.
The TSCAM schedules the traffic classes constant bit rate (CBR), VBR, and best effort in a strict priority
in which CBR is the highest priority and best effort is the lowest priority. The best-effort traffic class
includes UBR, available bit rate (ABR) and UBR+ service categories. When traffic shaping is disabled
for all the traffic classes on a port, all the traffic from that port is switched unaltered as if it were a single
connection at the highest priority.
Note Traffic shaping in the TSCAM is disabled by default. Any changes to shaping configurations are
supported across switch reloads only.
An example of how the ATM TSCAM might work in a network is shown in Figure 23-1. In this example,
the TSCAM is in a Catalyst 8510 MSR switch router that is on the edge of a private enterprise network
connected to a public ATM network. The TSCAM helps ensure that the maximum number of cells
transmit through to the public network.
Figure 23-1 TSCAM on an Enterprise Private Network
ATM TSCAM Features
The ATM TSCAM offers the following benefits:
• Traffic shaping for up to four ports on any combination of T1, E1, and DS3 ports
• Traffic shaping for up to three ports on OC-3 ports
• Traffic shaping for up to one OC-12 port
• VC functionality for up to 32K VCs
• An aggregate bandwidth of OC-12
• Online insertion and removal (OIR)
Enterprise
Private
Network
Public
ATM
Catalyst 8510
MSR Switch Router
55886
Layer 3 switches
TSCAM
UPC
Public UNI
Drop/Tag
Cisco 7xxx
routers