Operational modes
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Overview of operational modes
These TransLAN
®
operational modes exist:
• Proprietary VPN modes:
– Multipoint LAN bridging mode (“LAN-VPN mode”, “MLAN mode”)
• Standard compliant IEEE modes:
– STP virtual switch mode compliant with IEEE 802.1Q
– STP virtual switch mode compliant with IEEE 802.1ad (“Provider bridge
mode”)
Virtual Switch operation mode
When the transparent tagging mode has been selected on the Ethernet Interface
extension card (LAN unit) level, a different Virtual Switch operational mode must be
chosen per Virtual Switch. The Virtual Switch can be configured in the following
operation modes:
• Repeater
• LAN-interconnect
• LAN-VPN (MLAN)
When the IEE802.1Q/IEEE 802.1a tagging mode has been selected, the operation mode
of the Virtual Switch is always Spanning Tree.
The physical Layer 2 (L2) switch that is present on an Ethernet LAN tributary board
can be split into several logical or virtual switches. A Virtual Switch is a set of
LAN/WAN ports on an Ethernet LAN tributary board that are used by different
VLAN’s which can share the common WAN bandwidth. Each of the virtual switches
can operate in a specific Virtual Switch mode depending on the VLAN tagging
scheme, and each Virtual Switch mode allows specific LAN-WAN port associations as
explained in the following paragraphs.
First the VLAN tagging mode has to be specified on LAN unit level, this can be either
IEEE 802.1Q/IEEE 802.1ad VLAN tagging or VPN (transparent) tagging. In VPN
tagging mode, end-user VLAN tags that optionally may appear in the end user traffic
are ignored in the forwarding process. These VLAN tags are carried transparently
through the ″TransLAN Network″. In VLAN-tagging mode, the VLAN tags are also
carried transparently, but the VLAN ID in the VLAN tags is used in the forwarding
decision. Therefore customers’ VLAN IDs may not overlap on a physical Ethernet
switch, the VLAN IDs must be unique per switch pack. (FEP 1_188_14221)
After having provisioned the tagging mode, per virtual switch a different Virtual
Switch operational mode may be chosen. The Ethernet LAN tributary board supports
either the Repeater mode, LAN-Interconnect, LAN-VPN, and Spanning Tree Protocol
Virtual Switch mode of operation. IEEE 802.1D MAC forwarding and address filtering,
multi-point bridging, and spanning tree protocol (STP) are supported under all modes
of operation, except the Repeater mode.
Traffic provisioning
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Alcatel-Lucent - Proprietary
See notice on first page
365-312-807R7.2
Issue 4, May 2007