Verilink QUAD/IMUX (880-502392-001) Product Manual - Manual (Page 72)

Performance Monitoring
5-4
Verilink QUAD/IMUX User Manual
AIS Rx/Tx Displays the number of Alarm Indication Signal (AIS) Seconds (received and
transmitted): A count of one-second intervals containing one or more AIS defects. AIS
is an unframed ALL-ONEs bit pattern that indicates an alarm condition exists
upstream in a circuit leading to the downstream equipment. This is also called an
ALL-ONEs Keep-Alive or Blue Alarm Signal. An AIS defect is declared when there are
three or fewer zeros in 512 bit times and there is an LOF defect. It is cleared when
there are three or more zeros in two frames or the LOF defect no longer exists.
RAI Rx/Tx Displays the number of Remote Alarm or Remote Alarm Indications (RAI) received
and transmitted. It is the alarm a receiving CSU sends to the other end of the circuit
when it detects a Loss of Signal or Loss of Frame. There is a 2- to 3-second
integration period upon detection of LOS or LOF before an alarm is sent to the far-
end equipment. This condition is also referred to as a Yellow Alarm.
SLIP Indicates a timing slip error condition.
CRC6 Cyclic Redundancy Check is an error-checking algorithm performed on data
transmissions. In simplified terms, for each extended superframe, a numerical value
is derived from the data in the bit stream at the transmit end. When each extended
superframe reaches the receive end, the cyclic redundancy check is calculated again
and compared with the value generated by the transmit-side data. Discrepancies
indicate one or more errors in the T1 facility.
BER EX Indicates that the configured Bit Error Rate threshold has been exceeded. The BER
threshold determines the level above which a CSU alarm is generated and reported.
Selecting 10E-9 will report more errors than 10E-4.
Restore State Shows the current condition of each port. OOS (Out Of Service) means that the port
has been removed from service by the IMUX 2160. If a port is removed from service,
it will not be placed back into service until the configured parameters for Line
Restoral are met. See the Line Restoral section in Chapter 3 (E1) or Chapter 4 (T1).
En Errored Seconds—The number of seconds that a CRC-6 error is detected on the line.
Un Unavailable Seconds—The number of seconds during which an Unavailable Signal
State occurs. This occurs after ten consecutive SES and clears only after ten
consecutive nonSES.
Bn Bursty Seconds—The number of one second intervals with between 2 and 319 CRC-6
error events. Bursty errored seconds are not counted when an SES or UAS is
counted..
Sn Severely Errored Seconds—A second with 320 or more CRC-6 error events, or one or
more OOF (Out Of Frame) events.
Ln LOS Seconds—The number of seconds during which there is a Loss Of Signal state.
Fn SEF Seconds—This error occurs when the frame alignment threshold of 10E-3 errors
in a given second is exceeded.
Dn LOF Seconds—The number of seconds during which there is a Loss Of Frame state.
On OOF Seconds—The number of seconds during which there is an Out Of Frame state.
An AIS Seconds—The number of seconds during which a pattern of unframed all ones
(Alarm Indication Signal) is received.
Cn Controlled Slip Seconds—The number of seconds during which recoverable timing
slips occurred.
Mn Loss of Frame Counts—The number of times frame sync has been lost.
Zn AIS/SEF Seconds—The total number of Severely Errored Seconds or AIS seconds
Qn Errored Seconds Type A—The number of seconds with only one CRC-6 error.
A Threshold Status—Displays the count, an indication if the threshold value has been
exceeded (Y or N), and the interval for LOF, LOS, RAI, AIS, and BPV.
Rn Reset Registers—Use this option to zero out all the performance and status registers.
X Exit this menu—Use this option to return to the Main Menu.
Field/Command Description