User guide

3-80 Packet Over SONET Module Installation and User Guide
Configuring the PoS Module
out-of-band Ethernet connection. All APS-related Ethernet communications between the
working router and the protection router are via UDP. Upon receiving the message, the
protection router invokes the APS protocol to request that the ADM switch to the
protection line. The APS protocol is carried in the K1 and K2 bytes of the SONET
overhead. The format of the K1 and K2 bytes is illustrated in Figure 3-15.
Figure 3-15: Format of SONET K1 and K2 Bytes
PoS_019
REQUEST
REQUEST
CHANNEL #
CHANNEL #
K1
bit # 1 4 5 8
CHANNEL #
ARCH
MODE /
INDICATION
0000
K1 - number of channel issuing request (1=>working, 0=>protection)
K2 - 0 if channel # in received K1=0, else channel # bridged to protection line
ARCHITECTURE
0 => provisioned for 1+1 architecture
MODE / INDICATION
0001
0010
0100
0110
1000
1010
1100
1110
1111
No Request
Do Not revert (nonrevertive only)
Reverse Request (bidirectional only)
Excercise
Wait-To-Restore (revertive only)
Manual Switch
Signal Degrade
Signal Fail
Forced Switch
Lockout of Protection
K2
Legend
bit # 1 4 5 6 8
100
101
110
111
Provisioned for Unidirectional Switching Mode
Provisioned for Bidirectional Switching Mode
Line Remote Defect Indication (RDI-L)
Line Alarm Indication Signal (AIS-L)