Installation and Operation Manual
Appendix
E Encapsulation over PSN
ACE-3105, ACE-3205 Ver. 5.2
3BATM Service Encapsulation
E-11
4 bytes Cell Header
N-to-One (N:1) ATM PW Encapsulation
In N-to-one (N:1) mapping mode (selectable), one or more ATM VCCs/VPCs are
mapped to a pseudowire link. The following figure illustrates the packet format in
N:1 mode:
0
0
0
0
flags (4 bits)
Reserved
length (6 bits)
Sequence number (2 bytes)
VPI (12 bits)
VCI (16 bits)
PTI/CLP
Figure
E-14. N:1 Encapsulation Structure
The following figure illustrates the multiple cells concatenation in N:1 mode:
0
0
0
0
flags (4 bits)
Reserved
length (6 bits)
Sequence number (2 bytes)
4 bytes cell header
Payload (48 bytes)
4 bytes cell header
Payload (48 bytes)
Figure
E-15. Multiple Cells Concatenation in 1:1 Encapsulation Mode
AAL5-SDU ATM PW Encapsulation
The AAL5-SDU control word for an ATM PW has the following structure:
0
0
0
0
T
E
C
U
Reserved
length (6 bits)
Sequence number (2 bytes)
Figure
E-16. AAL5-SDU Control Word Structure
ATM Control
ATM Control