Chapter 7 Managing Service Class Templates - Cisco MGX 8850 (PXM1E/PXM45) Configuration Manual

Managing Service Class Templates
A Service Class Template (SCT) is a file that contains default configuration data for switch connections
and for configuring the hardware to support connections. When you configure a connection, or when an
SVC is established, the switch analyzes the connection setup request data, any local configuration data,
and the SCTs that apply to the port and to the card. For example, if an SPVC configuration does not
include required data for the requested class of service (COS), default values from the SCT files are used.
If an SVC request or SPVC configuration specifies configuration values that are different from the SCT
values, the specified values override the default SCT values.
There are two types of SCTs: card SCTs and port SCTs. Card SCTs define configuration parameters for
the hardware that transfers data between the a service module and the switch back plane. You can assign
one card SCT to each service module.
Note The PXM1E supports port SCTs only. PXM1E cards do not support card SCTs.
Port SCTs define configuration parameters for the hardware that transfers data between a PXM1E or
service module and a communication line to another switch or CPE. Port SCTs are assigned when a port
is configured, and you can use different port SCTs on the same card, provided that the port SCT you
select is designed for that card type.
Some SCT parameters control the PXM1E or service module hardware, and others are used as default
values for connection parameters. A complete discussion of the SCT parameters is beyond the scope of
this book.
SCT parameters are used to do the following:
connection policing
•
• connection admission control (CAC)
provide default connection parameters
•
provide connection threshold parameters
•
• set up class of service buffer (COSB) parameters and threshold values
SCTs simplify configuration by providing default values that will work for most connections. This
reduces the number of parameters that need to be defined when setting up connections. When
configuring a service module card SCT, your goal should be to select the card SCT that will support the
majority of planned connections on that card. When configuring a PXM1E or service module port SCT,
your goal should be to select the port SCT that supports the majority of planned connections on that port.
Cisco MGX 8850 (PXM1E/PXM45), Cisco MGX 8950, Cisco MGX 8830, and Cisco MGX 8880 Configuration Guide
Release 5.0.10, OL-3845-01 Rev. B0, August 16, 2004
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