Ace ACE-3105, Инструкция по установке и эксплуатации

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Appendix E Encapsulation over PSN Installation and Operation Manual
E-10 3BATM Service Encapsulation ACE-3105, ACE-3205 Ver. 5.2
Table E-10. 1:1 Encapsulation Parameters
Parameter Name Purpose
Sequence
number An unsigned 16-bit rounded number for
guaranteeing an ordered packet delivery.
M Transport mode bit of the control byte; indicates
whether the packet contains an ATM cell or a
frame payload (cell mode = 0; frame mode = 1).
V Indicates whether the VCI field is present in the
packet; its value is either 0 or 1.
PTI The 3-bit Payload Type Identifier (PTI) value;
copied form the PTI bits of the encapsulated ATM
cell header.
C Indicates the CLP (Cell Loss Priority) value of the
encapsulated cell; copied from the encapsulated
ATM cell header.
VCI The 16-bit Virtual Circuit Identifier (VCI). Valid only
if V=1 (see above).
The following figure illustrates the multiple cells concatenation in 1:1 mode:
0 0 0 0 Reserved (4 bits)
Sequence number (2 bytes)
M V Reserved PTI C
VCI (2 bytes)
Payload (48 bytes)
M V Reserved PTI C
VCI (2 bytes)
Payload (48 bytes)
M V Reserved PTI C
VCI (2 bytes)
Payload (48 bytes)
Figure E-13. Multiple Cells Concatenation in 1:1 Encapsulation Mode
ATM Control
Cell Header
Cell Header
Cell Header