Definition of Terms/Acronyms
The following are terms and phrases used within this manual, or which are found in documents associated with this equipment.
1+1 | The Term “1+1” refers to line protection where identical |
| information is transmitted on two redundant lines. The Receiver |
| chooses the “best” line to use based on the BER of the line. |
AIS | Alarm Indication Signal: Used in T1 signaling, the AIS is a |
| predetermined bit stream (all ones) that is transmitted (forwarded) |
| upon the loss of an incoming T1 signal or when the T1 signal is |
| disrupted. |
AMI | Alternate Mark Inversion: A bipolar coding scheme used to |
| accommodate the ones density requirements of T1 lines in such a |
| way that successive ones, or marks, must alternate in polarity. AMI |
| is an older standard, but is still used for transporting voice |
| transmissions. |
AN | Auto Negotiation: A signaling protocol used by an Ethernet PHY to |
| determine the characteristics (speed, duplex mode) of its “link |
| partner” and configure itself automatically |
B8ZS | Bipolar with |
| converts any string of 8 zeros of a |
| the far end is converted back to eight zeros. B8ZS coding actually |
| inserts Bipolar Violations (BPVs) that are realized at the next |
| multiplexer point and are taken out of the signal. |
BER | Bit Error Rate: The percentage of bits with errors divided by the |
| total number of bits that have been transmitted, received or |
| processed over a one second time period. |
CLI | Command Line Interface: An interface screen, often |
| used for system management and diagnostics requiring the user to |
| type commands rather than use a GUI. |
CV | Code Violation: An anomaly of a decoded |
| stream resulting in coding (signaling) error(s). Noise bursts or |
| intermittent connections on a link are the usual causes of code |
| violations; an HDB3 coding error. |
DDMI | Digital Diagnostic Monitor Interface: A defined serial interface and |
| data format typically used to access SFP internal information |
26