Published on September 12th, 2011 | by Alexis Argent0
Why We Need Gigabit Networks
When GigaOm is talking about an elephant in the network room, they mean the problem of getting consumers to pay for gigabit class Internet service to their homes. It’s a problem because companies won’t provide high-bandwidth Internet services unless enough people have the connections, but homeowners have a hard time seeing the need to upgrade until the services exist first. Savvy customers also know that sometimes network latency is more important than a gigabit of bandwidth. So how much capacity do we need? A high-definition 2D video feed requires more than a few megabits, and many households want multiple of them so that everyone in the family can watch their own favorite programs. Add 3D video into the picture, plus future online gaming services, and there should be no trouble keeping a gigabit connection busy. “Build it and they will come.”
Bandwidth in computer networking refers to the data rate supported by a network connection or interface. Network bandwidth is not the only factor that contributes to the perceived speed of a network. A lesser known but other key element of network performance – latency– also plays an important role.
Introduction to Computer Network Speed
Bandwidth, latency and other factors in network performance
What Is Network Bandwidth?
Bandwidth is the primary measure of computer network speed. Virtually everyone knows the bandwidth rating of their modem or their Internet service that is prominently advertised on network products sold today.
In networking, bandwidth represents the overall capacity of the connection. The greater the capacity, the more likely that better performance will result. Bandwidth is the amount of data that passes through a network connection over time as measured in bps.
Bandwidth can refer to both actual and theoretical throughput, and it is important to distinguish between the two. For example, a standard dialup modem supports 56 Kbps of peak bandwidth, but due to physical limitations of telephone lines and other factors, a dialup connection cannot support more than 53 Kbps of bandwidth (about 10% less than maximum) in practice. Likewise a traditional Ethernet network theoretically supports 100 Mbps of bandwidth, but this maximum amount cannot reasonably be achieved due to overhead in the computer hardware and operating systems.
Broadband and Other High Bandwidth Connections
The term high bandwidth is sometimes used to distinguish faster broadbandInternet connections from traditional dialup or cellular network speeds. Definitions vary, but high bandwidth connections generally support data rates of minimum 64 Kbps (and usually 300 Kbps or higher). Broadband is just one type of high bandwidth network communication method.
Measuring Network Bandwidth
Numerous tools exist for administrators to measure the bandwidth of network connections. On LANs (local area networks), these tools include netperf and ttcp. On the Internet, numerous bandwidth / speed test programsexist, most available for free online use.
Even with these tools at your disposal, bandwidth utilization is difficult to measure precisely as it varies over time depending on the configuration of hardware and characteristics of software applications including how they are being used.