CANOGA PERKINS 9145EMP NID Software Version 4.0 - Manual (Page 196)

Configuring EVC 9145EMP NID Software User’s Manual
EVC Functionality
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Chapter 12
Configuring EVC
12.0 Introduction
The 9145EMP supports VLAN multiplexing of C-VLANs into S-VLANs. This feature allows
customer frames to be multiplexed into S-VLANs through the use of a C-VLAN/S-VLAN Map.
Each C-VLAN/S-VLAN map corresponds to an Ethernet Virtual Connection (EVC).
The C-VLAN/S-VLAN Map provides a means for ingress service frames at the User Ports to be
uniquely assigned to S-VLAN and forwarded out the Network Ports. Similarly, ingress service
frames at the Network Ports are forwarded to a unique User Port based on the S-Tag of the
frame. Optionally, a “tunnel tag” (T-Tag) may be added to the frames egressing on the Network
Port, between the S-Tag and the C-Tag. This tag can be used for tunnel topologies inside the
Service Provider's network.
12.1 EVC Functionality
This section briefly describes EVC functionality and the entities required for its configuration.
12.1.1 EVC Records
The EVC record is the entity that models the transport functionality of the system. There are a
maximum of 512 EVC records in the system.
An EVC record links a User port and a set of C-VLANs on that particular port, with a unique S-
VLAN on the network side. The record is uniquely identified in the system by the S-VLAN ID.
Service Multiplexing records and All-to-One Bundling records differ in the following ways.
• Service Multiplexing allows frames belonging to selected C-VLANs to be multiplexed in a
single S-VLAN on the network side. More than one service multiplexing record can be
configured on the same user port.
• An All-to-One Bundling multiplexing record indicates that all frames received on the spec-
ified user port, if they are C-VLAN tagged or untagged, are multiplexed in a single S-
VLAN tag.
The following restrictions are enforced for the consistency of EVC records:
• If a user port has All-to-One Bundling configured on it, no other EVC records can be con-
figured on that port. Similarly, if a Service Multiplexing record exists on a user port, no All-
to-One record can be configured on that particular port.