Cisco Headend System Release 2.5 Guía Del Usuario
4004831 Rev B
Overlay Technology
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VOD In an Overlay Environment
Overview
The most important aspect of Overlay technology is the manner in which digital
broadcast and VOD services are delivered to Cisco set-tops and non-Cisco set-tops.
Delivery of VOD Services
VOD services in an Overlay environment can be delivered either fully encrypted or
in the clear (unencrypted).
Clear VOD streams can be delivered by non-Cisco QAMs to Cisco set-tops. Cisco
Clear VOD streams can be delivered by non-Cisco QAMs to Cisco set-tops. Cisco
GoQAMs can also deliver clear VOD streams to non-Cisco set-tops.
The DNCS Session and Resource Manager (SRM) handles only Cisco set-tops in an
The DNCS Session and Resource Manager (SRM) handles only Cisco set-tops in an
Overlay environment. Although a Cisco set-top might request a VOD service from
either a Cisco or a third-party QAM, the DNCS SRM handles the session transactions
initiated by the Cisco set-top.
Support for Third-Party QAMS
The DNCS handles exclusive session requests from Cisco set-tops—for streams in
the clear—served by a non-Cisco QAM (third-party QAM).
If you have the Overlay technology installed on your system and are using QAMs
If you have the Overlay technology installed on your system and are using QAMs
from a vendor other than Cisco, add them to the DNCS. Third-party QAMs are
typically used to provide VOD services and for this reason are a part of a service
group. See Chapter 3, Managing VOD Sessions In an Overlay Environment, for
instructions on adding, modifying, and deleting third-party QAMs.