What is Broadband
Broadband is often referred to as high-speed Internet, because it has a higher data transmission rate than Dial-up. Generally, any connection of 256 kbit/s (0.256 Mbit/s) or more is considered broadband Internet although this does vary depending on who you ask. The International Telecommunication Union Standardisation Sector (ITU-T) recommendation I.113 has defined broadband as a transmission capacity that is faster than primary rate ISDN which is 1.5 to 2 Mbit/s. The US FCC definition of broadband is 200 kbit/s (0.2 Mbit/s) in one direction, and advanced broadband is at least 200 kbit/s in both directions. The Organization for Economic Co-operation and Development (OECD) has defined broadband as 256 kbit/s in at least one direction and this bit rate is the most common baseline that is marketed as "broadband" around the world. Personally, I refer to this as "Fraudband" because the Upload component is not much faster than a Dial-up connection. There is no specific bitrate defined by the industry, however, and "broadband" can mean lower-bitrate transmission methods. Some Internet Service Providers (ISPs) use this to their advantage in marketing a lower-bitrate connection as a broadband connection.
In reality, the advertised bandwidth is not always reliably available to the customer because ISPs generally oversell their capacity and allow a greater number of subscribers than their backbone connection can actually handle. Their assumption is that not all users will be using their full connection capacity at the same time. This strategy works most of the time so users are able to access their full bandwidth most of the time. However, peer-to-peer (P2P) file sharing systems, commonly used for music and video download, often require the higher bandwidth to function correctly. This can cause major problems for ISPs who have excessively oversold their capacity. This is why it is important to use a Quality VSP for your VoIP connection.
As the bandwidth delivered to end users increase, the market expects that products like Video on Demand (IPTV) services, streamed over the Internet, will become more popular, though at present such services generally require specialized networks. The data rates available on most broadband services still do not allow for good quality video, as MPEG-2 video requires about 6 Mbit/s for good results.
You may of noticed that this description uses the term "data transmission rate" instead of "speed". While it is common to use the term speed when talking about a broadband connect, ie "How fast is your broadband?", the fact is that the information travels from your place to the exchange at around the same speed no matter broadband plan you use. The easiest way to explain is to compare the water carrying capacity of a trickle irrigation system (Narrowband) compared to, say, a 3" Rural Pipe or Firemans hose (Broadband).
A Final word:
Speed of Light: 299,792,458 m/s (or 299,792.458 km/s) -- it's not just a good idea, it's the law!
Although often insignificant under in a Local Area Network, latency due to the speed of light can be a significant issue in WAN communication. Signals travel through copper wires and optical fibers at only about 60% of their speed in a vacuum. Hence a 3,000 km trip takes about 15 ms while a 6,400 km trip takes about 33 ms. As far as we know, the speed of light is a constant of the universe so we'd expect the latency it adds over a fixed path to also be constant.
- HowStuffWorks.com - DSL
- The UNH-IOL DSL Knowledgebase (advanced tutorials)
- To test the data transmission rate of your broadband connection, goto www.speedtest.net