363-206-285
Maintenance Description
9-54 Issue 3 June 2001
Unavailable Seconds (UAS-P) 9
An "unavailable second" is a second during which the DS3 path is "unavailable." A
DS3 path is considered "unavailable" from the beginning of X consecutive SES
until the beginning of Y consecutive seconds, none of which is severely errored. X
is equal to 10 seconds or, in the case of a failure, the DS3 signal failure. Y is equal
to 10 seconds of no SES or DS3 signal failures. If there is an unprotected DS3/
TMUX circuit pack failure, UAS are counted from within 1 second of circuit pack
failure to within 1 second of circuit pack recovery. UAS are counted and
thresholded independently for each DS3 path terminated by the system. This
applies to P-bit, adjusted F&M bit, and near-end and far-end C-bit options.
C-Bit 9
When the DS3 path PM C-bit option is selected, both near-end and far-end (far-
end block errors) PM data are monitored and displayed.
The system provides counts of DS3 C-bit CV-P, ES-P, SES-P, and UAS-P
incoming from both the DSX-3 and the fiber. The type of PM is provisioned per
DS3 service by a CIT command.
For C-bit PM, the DS3 service can be provisioned in VM or VMR modes. In VMR
mode, the C-bit errors are not corrected as in the P-bit option.
Quarter-hour and day registers are provided with provisionable TCAs. The TCAs
are provisionable on a per shelf basis. SEFS counts are also provided.
Table 9-6. DS3 Performance Monitoring (PM) Modes (Note)
Mode
PM
Option
Monitor
P-Bits
Monitor
F&M Bits
Monitor
C-Bits
Correct
P-Bits
Correct
F&M Bits
Correct
C-Bits
Monitor
Line PM
VMR P-Bit Yes No No Yes No No Yes
VMR F&M-bit No Yes No Yes No No Yes
VMR C-Bit No No Yes Yes No No Yes
VM P-Bit Yes No No No No No Yes
VM F&M-bit No Yes No No No No Yes
VM C-Bit No No Yes No No No Yes
CC P-Bit No No No No No No Yes
CC F&M-bit No No No No No No Yes
CC C-Bit No No No No No No Yes
Note: The BBG20 TMUX circuit pack is considered to be always in the VM mode.