Cisco BPX 8650, Installation And Configuration Manual

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Cisco BPX 8600 Series Installation and Configuration
Release 9.3.30, Part Number 78-12907-01 Rev. E0, May 2005
Chapter 25 Configuring SONET Automatic Protection System
APS 1:1 (Line Redundancy)
Step 4
Execute the following command, for example, for redundant line on port 1 for BXM OC-3 cards and
APS back cards in slots 2 and 3 of the BPX:
addcdred 2 3
Step 5
addapsln 2.1 3.1 1 { addapsln <slot.port> <slot.port> <1|2|3|..>
Note
The last entry, “1”, in the addapsln command specifies the type of APS, in this example APS
1+1.
Step 6
cnfapsln 2.1
Step 7 upln 2.1 {or uptrk , as applicable
APS 1:1 (Line Redundancy)
The APS 1:1 feature provides port and line redundancy for a single BXM front card and associated OC-3
or OC-12 redundant back card.
There is no new hardware required to support APS 1:1. A single front card with a standard back card is
used.
Two adjacent lines on the same card are used. The maximum number of connections supported by a
nonenhanced BXM card is reduced by half for APS 1:1 operation. Using enhanced BXM cards, the
number of available connections is not decreased.
Similarly to APS 1+1, SONET APS 1:1 requires that for every working line, there must exist a redundant
protection line (see Figure 25-6). However, unlike the 1+1 case, traffic protected by the redundancy must
be carried on the protection line
only when a failure occurs on the working line. In the case of no failure,
the protection line can transport idle traffic, ‘same’ traffic as working line, or extra traffic. Because the
protection line is not guaranteed to carry real traffic until the transmit end is informed of the failure and
switches, this coordination between the equipment at both ends is more complex.
Figure 25-6 SONET APS 1:1 Detail
Xcvr
Xcvr
Rx
Tx
Rx
Tx
Xcvr
Xcvr
Working line
Protection line
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