Cisco Headend System Release 2.7 Guide De Conception

 

4024319 Rev B 

1 

 

The growth in service bandwidth available to the cable service 
provider has far outpaced the increases in available access network 
bandwidth. This growth is due, in part, to upgrades and rebuilds. This 
same expansion of available services has also created a situation in 
which, at any given time and in any given service group, most services 
are not being viewed. Thus, bandwidth for an edge device (for 
example, a QAM modulator) and access network bandwidth is wasted 
because many of the services that are continuously broadcast to 
subscribers are not being watched. SDV is a technique that recaptures 
such potentially wasted access network bandwidth by delivering 
selected services only where and when users are actively requesting 
service. This technique is performed through program switching. 

This chapter provides a brief review of traditional linear broadcasting 
over a Hybrid Fiber-Coax (HFC) network and contrasts this with how 
SDV operates. In addition, this chapter describes the benefits of SDV 
to the cable service provider. 

 

 
 

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The Switched Digital Solution .............................................................. 3