Alvarion Technologies Ltd. BMAX-BA36 Manuale Utente

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Operation
Chapter 4 - Operation and Administration
4.11.1.5
Using VLANs and VPLs
VLANs can be used for creating within the BreezeMAX network virtual groups of 
multiple end-users (stations) belonging to the same organization (Subscriber). 
They may also be used to differentiate between different end-users (stations) 
connected to the same SU.
In the backbone, VPL ID (Virtual Private Link ID) is used. VPL is a virtual 
connection between two points on the network, such as a base station and a 
service provider or corporate network, identified by the VPL ID, with functionality 
that is similar to VLAN ID (VLAN on the backbone network). Typically, it is used to 
separate between different traffic types (e.g. Data and VoIP), or traffic to/from 
different ISPs or different corporate networks.
If the VPL ID is None (No VPL ID) and VLAN Transparency Mode is Off, frames 
arriving from the infrastructure side with a VLAN ID tag will be discarded. Tagged 
frames arriving from the wireless domain will be forwarded without a VLAN tag, 
unless 802.1p Priority Marking is used. If 802.1p Priority Marking is used, tagged 
frames will be forwarded with VPL ID = 0 and the defined Priority Marking Value.
If the VPL ID is other than None (applicable only if VLAN Transparency Mode is 
Off), all untagged frames forwarded to the network will be tagged with the VPL ID. 
The VLAN ID in tagged frames arriving from the wireless network will be replaced 
by the VPL ID.
The guidelines that should be followed when defining VPL ID are:
„
Several Service Profiles may share the same VPL ID. However, the following 
rules must be met:
‘
Any number of L2 and/or VoIP Service Profiles may share the same VPL ID, 
provided they all use the same Forwarding Rule.
‘
Any number of PPPoE Service Profiles may share the same VPL ID, 
provided they all use the same Forwarding Rule.
‘
Any number of L2, VoIP and PPPoE Service Profiles may share the same 
VPL ID, provided that all L2/VoIP Service Profiles use the same Forwarding 
Rule A, and all PPPoE Service Profiles use the same Forwarding Rule B, 
where A and B are different.
The VLAN Transparency Mode defines the method of transferring packets to the 
operator's upstream network. When set to On, data packets sent from the Base 
Station to the backbone will be transferred transparently. The VPL ID parameter 
is not applicable to Service Profiles with VLAN Transparency Mode On.