Bandwidths and Quality
These examples demonstrate the quality available at different bandwidths for the different streaming formats. You'll need the free players from RealPlayer, Quicktime, and Windows to view these materials.
Better quality is possible with higher bandwidths, but maintaining that bandwidth for an extended period may become a problem. To account for network fluctuations, aim for about 75% of the maximum bandwidth used by your target audience.
At Cornell, many off-campus students connect by cable modem or DSL. It is difficult to provide an exact estimate of the bandwidth students will experience. Cable varies between 1-6 Mbps, but it is shared, so the student gets only a fraction of the bandwidth available, depending on how many other users are on at the same time. DSL varies between 128Kbps-3Mbps. The upload bandwidth is often slower than the download, as well.
On-campus Cornell students use the high-speed campus network. Resnet is 10 Mbps in most cases, 100 Mbps in some; but it is shared so one person doesn't get it all. The writer of this paragraph ws getting about 3.5 Mbps at CIT.
Some on-campus Cornell students may use wireless. It's advertised as 54Mbps, but once again, it is shared, and relatively slow in actual use.
As network congestion occurs, the playback quality can degrade to the point where the video freezes and the audio breaks up. The more bandwidth required by a file, the more likely network congestion will occur. At this point the player will pause and rebuffer, and try to resume using a lower data rate.
Any regular system maintenance and server restarts for any of our services will be scheduled weekdays between 5:00 am and 7:00 am. All users should be aware that a system may become unavailable during this maintenance time.
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