Ports; Table 57 Possible User Re-Marking Of Qos Fields By Class Of Interface - Nortel business policy switch 2000 User Manual

Refer to
non-IP, and trusted, untrusted, or unrestricted ports.

Ports

BPS 2000 ports are classified into three categories: trusted, untrusted, and
unrestricted ports. These three categories are also referred to as interface classes.
In your network, trusted ports are usually connected to the core of the DiffServ
network, and untrusted ports are typically access links that are connected to end
stations. Unrestricted ports can be either access links or connected to the core
network.
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.
Table 57
for IP traffic (including layer 2 traffic matching IP) and layer 2, non-IP traffic.

Table 57 Possible user re-marking of QoS fields by class of interface

Type of filter Action
IP filter or DSCP
Layer 2 filter
matching IP
IEEE 802.1p
Drop precedence
Layer 2 filter DSCP
(non-IP)
Table 57 and Table 58
Note: Layer 2 filters should have the same evaluation order (or
precedence order) as shown in this example to ensure that IP traffic will
be treated properly.
shows the configurations available to the user for each class of interface
Trusted
Cannot re-mark
Cannot re-mark
Cannot re-mark
Cannot re-mark
Chapter 4 Policy-enabled networks 295
for more information on layer 2 traffic, either IP or
Untrusted
Must re-mark
Must re-mark
Must re-mark
Cannot re-mark
Using the Business Policy Switch 2000 Version 2.0
Unrestricted
Re-mark or not
Re-mark or not
Re-mark or not
Cannot re-mark