How Fast Does Your Network Need To Be?

Measuring the speed of a computer network can get complicated, but ultimately what matters to most people is how well the network responds when they are trying to accomplish some task. Just how fast your computer network needs to be depends on the usage model. In general, as more devices and people share a network, the network's overall speed (measured in terms of bandwidth and latency) must be to support the total load.

• Network Speed for Web Surfing

Basic Web surfing can be done over anyspeed of networking, including very slowdial-up Internet. The time required to a load a Web page increases significantly on low-speed connections, however.Broadband Internet connections of 512 Kbps or higher support Web surfing adequately, although higher speed connections help with pages that have embedded graphics and other rich content.

Besides network bandwidth, Web surfing is also sensitive to network latency. Web surfing over satellite Internet connections, for example, takes longer than for wired broadband Internet services offering the same bandwidth, due to the high latency of satellite.

• Network Speed for Email and IM

Sending text over computer networks requires minimal bandwidth. Even old, slow dial-up Internet connections adequately support instant messaging and Web-based email. However, large attachments sent through email or IM transfer slowly over lower-speed connections. A one megabyte attachment sent over a dialup may take 10 minutes or more to transfer across the connection, while the same attachment can send in only a few seconds over a good broadband link.

• Network Speed for Television and Movie Streaming

Video streams utilize more or less network bandwidth based on resolution and frame rate of the content being viewed along with the codec technology used to compress and decode the individual frames. Standard definition television, for example, requires 3.5 Mbps on average, while DVD movie quality steaming requires up to 9.8 Mbps. High-definition video television typically requires 10-15 Mbps, and Blu-ray video up to 40 Mbps. The actual bit rate of a given video fluctuates up and down over time based on the content; movies with complex imagery and greater movement require relatively more bandwidth.

• Network Speed for Video Conferencing

Required network speeds for video conferencing are similar to television, except that video conferencing products offer lower resolution and quality options that can reduce the bandwidth requirements considerably. Personal conferencing products like Apple iChat, for example, require 900 Kbps (0.9 Mbps) for a two-person video session. Corporate video conferencing products utilize more bandwidth up to standard definition TV requirements (3-4 Mbps), and three- and four-way sessions also increase the speed requirements further.

• Network Speed for Internet Radio (Audio Streaming)

Compared to video, audio streaming requires much less network bandwidth. High-quality Internet radio typically broadcasts at 128 Kbps, while podcast or music clip playback requires no more than 320 Kbps.