HDSL4 for General Distribution Installation and Maintenance Practice
HDSL4 Deployment Guidelines
61223HDSL4L2-5C
55
HDSL4 DEPLOYMENT GUIDELINES
The different segments of an HDSL4 circuit are defined in
.
Figure 52. HDSL4 Circuit Segments
NOTE
Four-segment, three-repeater support is a special case and will be
described separately
The ADTRAN HDSL4 system provides DS1-based services over loops designed to comply with
the guidelines given below. These guidelines apply to a single segment circuit (an HDSL4
circuit with no H4Rs), to a circuit having two segments (with one H4R), or to a circuit having 3
or 4 segments (with two or three H4Rs).
The guidelines reflected herein are for worst-case scenarios (i.e., for loops that contain a
maximum amount of disturbers, noise, etc.). Actual deployment guidelines may vary based on
local policy. Refer to those guidelines on an as-necessary basis to ensure optimum perfor-
mance.
Cable Characteristics for HDSL4
The loop (cable/wiring) deployment guidelines are as follows:
1. All loops are nonloaded only
2. Any single bridged tap is limited to 2 kft.
3. Total bridged tap length is limited to 2.5 kft.
4. Loop Attenuation Limits. See
.
Table 11. Attenuation limits
Segment
Recommended Maximum
Upstream
Downstream
1
st
30 dB
32 dB
2
nd
and 3
rd
28 dB
28 dB
1st Segment
H4TU-C
1st H4R
3rd H4R
2nd Segment
3rd Segment
H4TU-R
4th Segment
2nd H4R
