Table 57 Re-Marking Qos Fields By Class Of Interface Group - Nortel 2000 Using Manual

The classifications of trusted, untrusted, and unrestricted actually apply to groups
of ports (interface groups). Because a port can belong to only one interface group,
a port will be classified as trusted, untrusted, or unrestricted. These types are also
referred to as interface classes. So, you have three classes of interface groups:
Trusted, untrusted, and unrestricted.
By default, all ports are untrusted. You must configure the ports to be trusted.
Table 57
the type of traffic and class of interface group.

Table 57 Re-marking QoS fields by class of interface group

Type of filter Action
IP filter or DSCP
Layer 2 filter
matching IP
IEEE 802.1p
Drop precedence
Layer 2 filter DSCP
(non-IP)
IEEE 802.1p
Drop precedence
The Business Policy Switch does not trust the DSCP of IP traffic received from an
untrusted port, but it does trust the DSCP of IP traffic received from a trusted port.
Filters installed on trusted ports cannot change the DSCP of the IP packets
received on these ports. These filters specify an action that must change the IEEE
802.1p and drop precedence of the matching packets based on the incoming DSCP
using a table that matches each one of the 64 DSCP values to the corresponding
IEEE 802.1p priority. The values can be modified by a policy server or by the user.
shows the guidelines the switch uses to re-mark various fields based on
Trusted
Cannot re-mark
Uses the DSCP to
802.1p table to mark
Uses the DSCP to
802.1p table to mark
Cannot re-mark
Cannot re-mark
Cannot re-mark
Chapter 4 Policy-enabled networks 283
Untrusted
Must re-mark
Must re-mark
Must re-mark
Cannot re-mark
• Tagged—must re-mark
• Untagged—cannot
re-mark
• Tagged—must re-mark
• Untagged—cannot
re-mark
Using the Business Policy Switch 2000 Version 1.2
Unrestricted
Re-mark or not
Re-mark or not
Re-mark or not
Cannot re-mark
Re-mark or not
Re-mark or not