Hughes HX System, Обзор системы

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Chapter 7 • Multicast features
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Chapter 7
Multicast features
The HX System supports IP multicasting services. In this mode
of operation, the Internet protocol gateway (IPGW) forwards
multicast data (bandwidth-intensive, timing sensitive rich-media
data such as digital audio and video broadcasts) and streams it out
to remote sites that are enabled, via the conditional access system
(CAS) to receive the multicast stream. Additionally, the IP
gateway can be configured with minimum and maximum
committed information rate (CIR) thresholds for each application,
as well as CIR for the entire gateway (based on the contracted
grade of service).
This chapter describes the multicast applications supported by the
HX system and the methods used in the HX gateway and satellite
routers to implement multicast support, addressed in the
following sections:
•
Multicast applications on page 59
•
HX gateway multicast management on page 60
•
Satellite router multicast support on page 60
Multicast applications
The HX System uses multicasts for a number of purposes, such as
transmitting control information and configuration files generated
by the Vision UEM system, and for transmitting IGMP protocol
traffic such as conferencing, streaming media or other multicast
media. Network time protocol messages are also multicast. From
the end user perspective, the most important of these is IGMP
protocol support.
Broadcast applications Broadcast enterprise file transfers can be sent to all members of
an enterprise network, with payloads that can provide piped-in
music or advertisements used in retail locations. The Hughes
system supports broadcast applications with the addition of an
optional enterprise package delivery (EPD) server. You define the
content and the package distribution to initiate the broadcast
application.