Cabletron Systems CSX1200, CSX1000 manual Robbed Bit Signaling is not supported for the CyberSWITCH

CONFIGURING RESOURCES AND LINES

Lines

DIGITS VERIFIED

The number of digits to verify (starting at the rightmost digit), so that when the system receives a phone call it can determine on which bearer to accept the phone call. The maximum number of digits should be 7, which is the default value in most cases.

FRAMING TYPES

For primary rate lines only. The normal line transmission method employed on a PRI line is a time- division multiplexed (TDM) scheme of repeating fixed-length frames. For T1 lines, of each frame, a single bit is used to convey such things as a frame alignment pattern, data checksums, and in more advanced networks, maintenance commands, between the network and the Customer Premise Equipment (CPE). For E1 lines, all of channel 0 is used for this. The two most common framing types for PRI/T1 lines are SF and ESF, which are 12- and 24-frame formats, respectively. E1 lines can use one of three framing types: doubleframe, multiframe with no CRC, or multiframe with CRC, with the most common being multiframe CRC.

LINE ENCODING

For Primary Rate lines only. Line encoding specifies the nature of the signals that are used to represent binary one and zero at the physical layer. Two encoding methods are Alternate Mark Inversion (AMI) and Bipolar 8 Zero Substitution (B8ZS). AMI as the encoding scheme implies that the applications using the transmission line must guarantee a certain number of 1s in the signal to help prevent a loss of synchronization in the network. This is possible if the voltage level of the signal remains zero for too long a period of time (i.e., too many logical 0s in the transmitted data). B8ZS enforces no such limits on the application using the transmission medium since it introduces bipolar violations in the signal. These violations are in turn interpreted at the receiving end not as errors, but simply as the substitution of a 1 for a 0 after certain number of consecutive 0s were detected in the transmitted signal.

SIGNALING METHOD

For primary rate lines only. The signaling method dictates how and where the call signaling is to be carried. The two methods available are Common Channel and Robbed Bit Signaling.

COMMON CHANNEL

In the Common Channel signaling case, one of the 24 channels of the PRI frame is devoted to call control messaging.

ROBBED BIT SIGNALING

Robbed Bit Signaling is not supported for the CyberSWITCH.

LINE BUILD OUT

For primary rate lines only. No matter what the quality of the cabling employed in a network, each and every line experiences some signal loss or degradation. Line Build Out describes the degree of attenuation to be applied to the transmission signal in order to have the correct signal levels and shape arrive at the receiver. Generally, the longer the line connecting the CPE and the network equipment, the less the transmitted signal is attenuated.

CFGEDIT will use short or long haul information to determine the correct Line Build Out (i.e., degree of attenuation) for your lines. The value you input (in CFGEDIT) to determine attenuation depends on whether or not you are using an external Channel Service Unit (CSU).

If you are using an external CSU, you will specify a value under Short Haul Build Out. Specify the length of the line, in meters, from CPE to the CSU by selecting a range from zero to 210 meters.

Workgroup Remote Access Switch 97