Alcatel-Lucent 1643 AMS User's Operation Manual page 379

Traffic provisioning
The following applies to port groups or virtual switches, respectively:
• A virtual switch defines a spanning tree domain, and can be assigned a mode of
operation (LAN interconnect, LAN-VPN, IEEE 802.1Q, IEEE 802.1ad (PBM)).
• A virtual switch includes any number (at least 2) of external Ethernet LAN ports
and/or internal WAN ports associated with a VC-n-Xv payload.
• Per data pack a VLAN ID can only be used in one virtual switch. This means that
a VLAN must have all its port members inside one single virtual switch. Learning
the same VLAN dynamically via GVRP on another virtual switch of this data pack
should be prevented by network design.
• Traffic between virtual switches of the same physical switch is not possible.
• Each port can be a member of only one virtual switch at a time.
In the following example, a virtual switch is provisioned that connects 2 LAN ports
with 1 WAN port:
Supported frame sizes
The 1643 AM support Ethernet frames of up to 1650 bytes. The X8PL card of the
1643 AM supports Ethernet frames of up to 1600 bytes.
Ethernet encapsulation with GFP
The generic framing procedure (GFP) is used to adapt the asynchronous Ethernet
payload to the synchronous SDH server layer.
A GFP-header (eight octets) is prepended to each Ethernet frame to indicate frame
length and payload type. Gaps between Ethernet frames are filled with "IDLE" frames
(four octets each).
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365-312-807R7.2
Issue 4, May 2007
Virtual switch
LAN
LAN
LAN
ports
Alcatel-Lucent - Proprietary
See notice on first page
SDH transport
network
TransLAN physical
Ethernet switch
WAN
ports
Ethernet over SDH
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