User guide

DISPLAY CONTENT MANAGER — Installation and User Guide 297

Create a Group Object

Video on Demand (VOD)

Content is downloaded on request in real time to the client (set-top box or

computer) requesting the content. VOD client users may select video clips

stored on the server for viewing, either from a dynamically updating menu,

or through direct channel number selection via the remote control. The user

can pause, stop and resume viewing content at any time. Content chapter

points can be created for faster navigation, and clients can fast-forward or

rewind video clips during playback.

Unicast

Unicast is a one-to-one connection between the client and the server as

illustrated in Figure 383. Unicast uses IP delivery methods such as Trans-

mission Control Protocol (TCP) and User Datagram Protocol (UDP), which

are session-based protocols. When one or more clients connect using

unicast to a MediaEdge server, the client has a direct relationship to the

server. Each unicast client that connects to the server takes up additional

bandwidth. For example, if you have 10 clients all playing 100-kilobits per

second (Kbps) streams, those clients as a group are taking up 1,000 Kbps. If

you have only one client playing the 100 Kbps stream, only 100 Kbps is

being used.

Figure 383. Unicast Delivery

Multicast

Multicast is a true broadcast. The multicast source relies on multicast-

enabled routers to forward the packets to all client subnets that have clients

listening. As illustrated in Figure 384, there is no direct relationship

MediaEdge Server

HDMA-4000/4100

STB3/STB4/STB4H

SWT3-DS/SWT4

Unicast Delivery

100 Kbps per client