Alcatel-Lucent 7750 SR-OS, Руководство по настройке

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Filter Policies
7750 SR OS Router Configuration Guide Page 423
VID Filters
VID Filters are a type of MAC filters that extend the capability of current Ethernet Ports with null
or default SAP tag configuration to match and take action on VID tags. Service delimiting tags (for
example QinQ 1/1/1:10.20 or dot1q 1/1/1:10, where outer tag 10 and inner tags 20 are service
delimiting) allow fine grain control of frame operations based on the VID tag. Service delimiting
tags are exact match and are stripped from the frame as illustrated in
Figure 19 . Exact match or
service delimiting Tags do not require VID filters. VID filters can only be used to match on frame
tags that are after the service delimiting tags.
With VID Filters operators can choose to match VID tags for up to two tags on ingress or egress or
both.
• The outer-tag is the first tag in the packet that is carried transparently through the service.
• The inner-tag is the second tag in the packet that is carried transparently through the
service.
VID Filters add the capability to perform VID value filter policies on default tags (1/1/1:* or 1/1/
1:x.*, or 1/1/1/:*.0), or null tags ( 1/1/1, 1/1/1:0 or 1/1/1:x.0). The matching is based on the port
configuration and the SAP configuration.
In the industry the QinQ tags are often referred to as the C-VID (Customer VID) and S-VID
(service VID). The terms outer tag and inner tag allow flexibility without having to refer to C-TAG
and an S-TAG explicitly. The position of inner and outer tags is relative to the port configuration
and SAP configuration. Matching of tags is allowed for up to the first two tags on a frame. Since
service delimiting tags may be 0, 1 or 2 tags.
The meaning of inner and outer has been designed to be consistent for egress and ingress when the
number of non service delimiting tags is consistent. Service 1 in
Figure 19 shows a conversion
from qinq to a single dot1q example where there is one non-service delimiting tag on ingress and
egress. Service 2 shows a symmetric example with two non-service delimiting tags (plus and
additional tag for illustration) to two non-service delimiting tags on egress. Service 3 illustrates
single non-service delimiting tags on ingress and to two tags with one non-service delimiting tag
on ingress and egress.
SAP-ingress QoS setting allows for MAC-criteria type VID which uses the VID filter matching
capabilities
QoS and VID Filters (moved to QoS guide) on page 313 .
A VID filter entry can also be used as a debug or lawful intercept mirror source entry.