Bandwidth (computing)

In computer network and computer science, digital bandwidth or just bandwidth means the amount of data that can be sent from one point to another in a certain period of time. It is measured as a bit rate expressed in bits per second (bits/s) or multiples of it (kbit/s Mbit/s etc.)

Digital bandwidth should not be confused with:

• Network throughput: which is the average rate of successful data transfer through a connection.
• Data transfer: which is the quantity of data transferred over a given period of time.

Bandwidth in web hosting

In web hosting, the term "bandwidth" is often used to describe the amount of data transferred to or from the website within a defined period of time. Another more specific phrase used for this meaning of bandwidth is monthly data transfer.

Web hosting companies often quote a monthly data transfer for a website, for example 500 gigabytes per month. If the total amount of data downloaded from the website in a particular month reaches this limit, the hosting company may shut off further public access to the site.

Internet connections bandwidths

Bandwidth	Connection type
56 kbit/s	Modem / Dialup
1.544 Mbit/s	T1
10 Mbit/s	Ethernet
11 Mbit/s	Wireless 802.11b
43.232 Mbit/s	T3
54 Mbit/s	Wireless-G 802.11g
100 Mbit/s	Fast Ethernet
155 Mbit/s	OC3
300 Mbit/s	Wireless-N WiFi
622 Mbit/s	OC12
1000 Mbit/s	Gigabit Ethernet
2.5 Gbit/s	OC48
9.6 Gbit/s	OC192
10 Gbit/s	10 Gigabit Ethernet

Broadband

Sometimes, the word "broadband" is used to mean "high-speed", especially with high-speed internet connections. "Broadband" means "wide band", and suggests high-speed. However, the term is not clear; "high-speed" is more clear. A dial-up telephone connection is most often thought to be low-speed, at less than 56,000 bit/s (bits per second). High-speed is usually 200,000 bit/s or faster. DSL (Digital Subscriber Line) or Cable modem connections are usually high-speed.