User guide

Network Engineering Video Services provided by ADSL
3-5
Telesyn Service Guide (Optimizing Video Services)
3.2.4 Network Engineering
The following rules should be followed when determining the number of set top boxes to provision on a port.
3.2.4.1 ANNEX A and ANNEX B ADSL cards
ADSL cards come in two version, ANNEX-A and ANNEX-B. The Annex A ADSL card provides service to
ports as described in ITU-T Recommendation G.992.
The Annex-B card has the same card type (ADSL16) but a different model number, ADSL16B. Annex B allows
ISDN Basic Rate Access and ADSL services to co-exist over the same subscriber line. GDMT and AUTO are
supported for Annex B, but the new ADSL2+ mode (as well as T1.413 and GLITE) is not supported for Annex
B. There is no version of ADSL8S that supports Annex B.
Note: Separate software loads files are used for ANNEX A and ANNEX B ADSL cards.
For information on hardware and components extending from the Telesyn system to the subscriber, see the Tele-
syn Wiring Guide.
3.2.4.2 Engineering of Set Top Boxes per ADSL Card and Port
Although the provisioning below specifies the ADSL16, it would be similar for the ADSL8S and ADSL24.
3.2.4.2.1 Maximum Number of STBs per Individual ADSL Port
There is a finite amount of bandwidth available on an ADSL16 line, so there are limiting factors to the number of
set top boxes that can be supported on any individual line. These factors are based on:
• the maximum bandwidth of the video streams
• overhead for transmitting over ADSL16
IP Filtering Y
ARP Filtering Y
MAC Limiting Y
Remarking N
Ingress Metering/Policing Y
Queue Mapping Y
Egress Rate Limiting N
No. of Queues 8
ACL Y
TABLE 3-1 Feature Interactions for ADSL Video Service (Continued)
Feature Supported? Notes