About Virtual Connection Endpoints (VCEs)

VCE is a constituent element of VCA and an abstraction of an 802.1Q VLAN bridge component. A VCA (Virtual Connection Access) is used to connect one or more virtual connection endpoints (VCE) together to complete the description of the end-to-end connectivity between two ports on an Accedian Edge Element. For more information, see section "About Virtual Connection Access (VCAs)". The VCE manipulates only one VLAN and consists of two termination points, labelled TP-A and TP-Z. TP-A defines the incoming port and TP-Z defines the outgoing port. Relay action and frame type complete the definition, as shown in figure below. For more information, see Application Note 200: Configuring SOAM with Virtual Connections.

The VCA/VCE defines traffic forwarding within an Accedian product. The connectivity is defined from the direction of the TP-A to TP-Z endpoints on one or more VCE elements. The end-to-end connectivity from TP-Z to TP-A is automatically inferred and symmetric with endto- end definition of TP-A to TP-Z, as shown below. The TP A (Termination Point) defines the incoming port and TP Z defines the outgoing port. The Relay action and Frame Types define the action to transform the incoming frames TP A toward the TP Z. The traffic is not restricted to being forwarded from "TP-A" to "TP-Z", The TP A and TP Z are there only to define the direction for the configuration.

Parts of a VCE

• Frame types: Defines the incoming frames as: vlan-tagged, untagged, any, and all-toone.
• Relay actions: Defines the action that be perform. These are:
• Tag (add a VLAN tag). the VLAN tag is added from TP A toward TP Z. In the reverse direction the VLAN tag is removed for traffic coming from TP Z toward TP A.
• Untag (remove a VLAN tag), the VLAN tag is removed from TP A towards TP Z. In the reverse direction the VLAN tag is added for traffic coming from TP Z toward TP A.
• Translate (change VLAN ID), the TP A VID is translated to TP Z VID for traffic going from TP A toward TP Z. In the reverse direction, the TP Z VID is translated to TP A VID for traffic going from TP Z towards TP A.
• Preserve (preserve the VLAN tag), the VLAN is the same on both TP A and TP Z. Revision 1