Appendix
E Encapsulation over PSN
Installation and Operation Manual
E-12
4BTDM Service Encapsulation
ACE-3105, ACE-3205 Ver. 5.2
Table
E-11. AAL5-SDU Control Word Parameters
Parameter Name
Purpose
Reserved
Reserved for future use; assigned with 0 value.
T
Transport type bit. If set to 1, the packet contains
an ATM admin cell. If not set, the PDU contains
an AAL5 payload.
E
EFCI bit. Set to 1 if the EFCI bit of one or more
cells in the AAL5 CPCS-SDU is set also to 1.
Otherwise, it is set to 0.
C
CLP bit. Set to 1 if the CLP bit of one or more cells
in the AAL5 CPCS-SDU is set also to 1. Otherwise,
it is set to 0.
U
Command/response field bit. Set to 0.
Sequence number
A 16 bits, unsigned and rounded number that can
be used to guarantee ordered packet delivery.
E.4
TDM Service Encapsulation
TDM traffic can be encapsulated over PSN in two modes:
•
CESoPSN – CES (Circuit Emulation Services) over PSN
•
SAToP – Structure-Agnostic over Packet.
Accordingly, the TDM Control Word frame is structured differently for each
encapsulation mode. For the TDM payload illustration, see
.
CESoPSN Control Word
The following figure illustrates the structure of the CESoPSN Control Word:
0
0
0
0
L
R
M
FRG
LEN (6 bits)
Sequence number (2 bytes)
Figure
E-17. CESoPSN Control Word Structure
Table
E-12. CESoPSN Control Word Parameters
Parameter Name
Purpose
Bits 0–3
Structure bits that their value must be zero
L
If set, indicates that the TDM data carried in the
payload in invalid due to a TDM circuit failure
R
Remote receive failure (PSN RDI) on the PSN side
