Description: This variable indicates the variety of DS1 Line implementing this circuit. The type of circuit affects the number of bits per second that the circuit can reasonably carry, as well as the interpretation of the usage and error statistics.

The reasons behind adding 'cds1Linetype' object (apart from 'dsx1LineType' in DS1-MIB.my) for 'line type', with enums from 'other(1)' to 'dsx2E2(11)' replicated, are following: 1) Addition of the two new enums (viz. 'dsx1E1Q50' and 'dsx1E1Q50CRC') in the standard DS1-MIB might not take place in near future; that's why it was decided to have a new object 'cds1LineType'. 2) A way was needed to be provided to configure 'line type' from CLI (Command Line Interface) for service modules supporting line type values from 'dsx1LineType' as well as 'cds1LineType', without having to modify two separate parameters and at the same time, making sure that CLI parameter values directly map to the MIB values.

Hence, enums from 'other(1)' to 'dsx2E2(11)' from object 'dsx1LineType' are replicated, and the new enums are added as 'dsx1E1Q50(20)' and 'dsx1E1Q50CRC(21)'. The gap between 'dsx2E2(11)' and 'dsx1E1Q50(20)' provides a safe margin in the case of modifications in 'dsx1LineType' in future; so the CLI can still have the same enums as the standard MIB.

It is to be noted that objects 'dsx1LineType' and 'cds1LineType' are mutually exclusive. Setting both in a SET request (with the exception of value 'other(1)') should result into an 'INCONSISTENT VALUE' error.

In the case of successive 'SET' requests, the value associated with the latest request should prevail irrespective of the object ('dsx1LineType' or 'cds1LineType') used.

Following values reflect the corresponding values in 'dsx1LineType' object in DS1-MIB.

dsx1ESF Extended SuperFrame DS1 (T1.107) dsx1D4 AT&T D4 format DS1 (T1.107) dsx1E1 ITU-T Recommendation G.704 (Table 4a) dsx1E1-CRC ITU-T Recommendation G.704 (Table 4b) dsxE1-MF G.704 (Table 4a) with TS16 multiframing enabled dsx1E1-CRC-MF G.704 (Table 4b) with TS16 multiframing enabled dsx1Unframed DS1 with No Framing dsx1E1Unframed E1 with No Framing (G.703) dsx1DS2M12 DS2 frame format (T1.107) dsx1E2 E2 frame format (G.704)

The recommended value for 'dsx1LineType' object is 'other'(1) for following values.

dsx1E1Q50(20) ITU-T G.704 with TS16 bits 5,7,8 set to 101. In all the other cases TS16 bits 5,7,8 set to 111.(Table 14) dsx1E1Q50CRC(21): dsx1E1Q50 with CRC.

For clarification, the capacity for each E1 type is as listed below: dsx1E1Unframed - E1, no framing = 32 x 64k = 2048k dsx1E1 or dsx1E1CRC - E1, with framing, no signalling = 31 x 64k = 1984k dsx1E1MF or dsx1E1CRCMF - E1, with framing, signalling = 30 x 64k = 1920k

For further information See ITU-T Recomm G.704