(1) See
in-system programmable.
(2) (
Image
Signal
Processor) See
image processor.
(3) (
Internet
Service
Provider) An organization that provides access to the Internet. Also called an "Internet host," an ISP connects to users via cable, DSL or FiOS; however, ISPs can also deliver service via satellite, dial-up, ISDN, private lines and wireless. Customers are generally billed a fixed rate per month, but other charges may apply. Some ISPs have a limit on the amount of data transfer per month and charge extra for overage (see
data cap). See
The World,
DSL,
cable Internet,
FiOS,
T1,
T3,
WISP and
SISP.
Your Own Website
ISPs often host a small website for their customers, allowing them to have a presence on the Web. However, the website may be limited to a maximum number of pages, and the domain name of the ISP becomes part of the customer's URL address. For a fee, an ISP may host a website that uses its customer's proprietary domain name (see
Web hosting). See
download vs. upload,
IXP and
backbone.
The Cellular Carrier Is Your ISP
For smartphone users, the ISP is the cellular carrier, such as Verizon and T-Mobile. Monthly plans are available for unlimited data or per gigabyte. See
carrier data plans.
How They're Connected
Small ISPs hook into regional ISPs or directly into major backbone providers. This diagram shows a local ISP confined to a single county, and a regional ISP confined to a state. In practice, ISP networks often have irregular boundaries that span jurisdictions.
ISP Architecture
This diagram shows how a typical, small ISP might be connected to the Internet.