Apple QuickTime Streaming Server Darwin Streaming Server manual Prepare the Network

mWindows can cause lighting problems. For more control, you should be able to draw the blinds and supplement room lights with a portable lighting kit that can be quickly set up for a live session.

Step 2: Prepare the Network

Check that there is an Ethernet connection to the classroom or lecture hall where the live broadcast is to take place. Install, repair, or replace cables and connectors as needed, using high-quality materials.

Bear in mind that streaming—especially live streaming—can make heavy demands on network resources, especially available bandwidth. To ensure that the network can handle the extra load, it may be necessary to do some or all of the following:

mDetermine the capacity of the existing network and calculate the anticipated additional traffic generated by live and on-demand streaming.

mDraw a map of bandwidth segments on your network, listing the capacity between all points.

mDetermine which applications are used in your network, their use patterns, where they are hosted, and the bandwidth they normally use during peak and off-peak times.

mBased on the configuration and capacities of your network, select the appropriate place to install your streaming server, avoiding potential bottlenecks.

mIf necessary, add capacity to the network (additional T1 lines, routers, switches, and so on) to handle the anticipated maximum number of concurrent viewers of live broadcasts in addition to other peak network traffic.

Keep in mind that a typical local network provides bandwidth internally of 10–100 Mbps. In contrast, a T1 line, frequently used to connect to the Internet, provides only about 1.5 Mbps of bandwidth.

T1 lines work fine for HTTP and FTP, where the requests are either short lived or are not time sensitive, but streaming is much more demanding. With streaming you can’t slow things down. The data has to be transferred at least as fast as the original content data rate in order to deliver streams.

For this example, we will assume a maximum of 10 concurrent viewers, half on the local network and half on the Internet and a bit rate for each unicast stream of approximately 256 kilobits per second (Kbps). The peak extra bandwidth needed is then about 3.2–3.3 megabits per second (Mbps). This estimate includes an extra margin of 25–30 percent for unplanned network congestion and peaks in the transmitted streams that can occur for various reasons.

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