Cisco Headend System Release 2.7 디자인 가이드
The Switched Digital Solution
4024319 Rev B
3
The Switched Digital Solution
Overview
The advent of SDV technology promises to fundamentally change the way the
industry delivers digital entertainment. With SDV, service providers have the ability
to offer a wider variety of programming while managing HFC network bandwidth
in a sustainable way.
industry delivers digital entertainment. With SDV, service providers have the ability
to offer a wider variety of programming while managing HFC network bandwidth
in a sustainable way.
In a manner similar to a telephone system, which switches a smaller number of lines
upon the demand of a larger number of customers, the SDV architecture switches
only selected content onto the HFC upon the demand of one or more viewers. Thus,
content that is not requested by anyone in a service group does not occupy HFC
bandwidth or require edge modulator resources.
upon the demand of a larger number of customers, the SDV architecture switches
only selected content onto the HFC upon the demand of one or more viewers. Thus,
content that is not requested by anyone in a service group does not occupy HFC
bandwidth or require edge modulator resources.
With SDV, popular content continues to be broadcast continuously, while less
popular content is held back and transmitted only upon request. Unlike video-on-
demand (VOD), with SDV (after the content is transmitted) that stream is shared by
any subsequent viewers requesting the same content within the same service group.
popular content is held back and transmitted only upon request. Unlike video-on-
demand (VOD), with SDV (after the content is transmitted) that stream is shared by
any subsequent viewers requesting the same content within the same service group.
SDV also provides access to broadcast service while VOD is retrieving stored content
from a server. As a result, SDV still uses the broadcaster's schedule to determine
when a program airs.
from a server. As a result, SDV still uses the broadcaster's schedule to determine
when a program airs.
The following diagram illustrates the typical SDV broadcast flow.