Pbb Technology; Figure 60: Qinq Payload In Provider Header Example - Alcatel-Lucent 7210 SAS M Service Manual

PBB Technology

IEEE 802.1ah specification encapsulates the customer or QinQ payload in a provider header as
shown in
1
I-PCP
8 6 5 4 3 2 1
Octets
1
Bits
PBB adds a regular Ethernet header where the B-DA and B-SA are the backbone destination and
respectively, source MACs of the edge U-PEs. The backbone MACs (B-MACs) are used by the
core N-PE devices to switch the frame through the backbone.
A special group MAC is used for the backbone destination MAC (B-DA) when handling an
unknown unicast, multicast or broadcast frame. This backbone group MAC is derived from the I-
service instance identifier (ISID) using the rule: a standard group OUI (01-1E-83) followed by the
24 bit ISID coded in the last three bytes of the MAC address.
The BVID (backbone VLAN ID) field is a regular DOT1Q tag and controls the size of the
backbone broadcast domain.
The following ITAG (standard Ether-type value of 0x88E7) has the role of identifying the
customer VPN to which the frame is addressed through the 24 bit ISID.
7210 SAS M Services Guide
Figure 60.
Res2
2-4 5-10
I-SID C-DA

Figure 60: QinQ Payload in Provider Header Example

11-16
C-SA
2-4
2+2
6+6
22B
(No FCS/Preamble)
Virtual Private LAN Services
Payload
Ethertype
C-VID
Ethertype
S-VID
Ethertype
C-SA
C-DA
I-TAG
802.1ad
Ethertype
B-VID
Ethertype
B-SA
B-DA
OSSG192
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