An ISP or Internet Service Provider, also called an internet access provider, provides customers access to the internet and other web services like email, domain name registration, web hosting and access to software tools. As the name suggests, an ISP does not have any other function apart from delivering internet services.
Internet Service Providers’, ISP – primary function is to provide internet access, using a range of available technologies ranging from modems to telephone lines, television cable to wireless Ethernet (Wi-Fi) and fiber optics. Higher-speed DSL networks also exist in the form of Ethernet, metropolitan Ethernet and gigabit Ethernet with speeds of 10 mbps, 100 mbps and 1000 mbps respectively.
Mailbox providers – A mailbox provider hosts electronic mail domains in email servers with storage access for mail boxes. Some of the common protocols in use are Simple Mail Transfer Protocol (SMTP), Internet Message Access Protocol (IMAP) and Post Office Protocol (POP).
Hosting ISP – provides web hosting, virtual server, cloud services, and online storage solutions.
Transit ISP – is an ISP that pays upstream ISPs, which usually have a larger network for internet access. These ISPs provide extra bandwidth for connecting hosting ISPs and access ISPs.
Virtual ISP – A virtual ISP buys services from another ISP, called a wholesale ISP, which enables the VISP’s users to access the internet utilising the services and infrastructure operated and owned by the wholesale ISP.
Free ISP – is an internet service provider that provides internet free of charge. Some free ISPs called free-nets are run on a non-profit basis, usually with volunteers.
Wireless ISP – As the name suggests, this is an internet service provider that provides broadband internet services wirelessly.
Dial up internet – is a service that provides connectivity to the internet through a standard telephone line. An individual user will be able to access the internet by connecting one end of the telephone line to the modem attached to the computer and the other end to the phone jack and having the computer dial a specific number provided by the ISP. The modem can be internal or external depending on whether it is installed in a free slot of the computer or connected through cables.
ADSL – stands for Asymmetric Digital Subscriber Line and is a type of digital subscriber line technology for data communication that provides quicker data transmission via copper telephone wires when compared to a traditional voice-band modem. The frequencies not utilised by a telephone voice call are used for this purpose. A DSL filter or splitter enables the use of one telephone connection for both voice calls and ADSL service simultaneously.
Cable modem – provides bi-directional data communication via radio frequency channels on a hybrid fiber-coaxial (HFC). A cable modem delivers broadband internet access utilising the high bandwidth of a HFC.
Wireless Internet – is the availability of broadband internet service without cables or wires using a special wireless technology called Wi-Fi.
Fiber-optic services (FIOS) – is a broadband network service that uses high-speed optical fibers to provide last mile connectivity.
ISPs govern the connection speeds they deliver to customers and their service offering differs around the world. Countries that are on the path of major underwater sea cables are the ones that generally have better service in terms of speeds. Having said that, most of North America, Europe and parts of Asia have access to high-speed internet, but countries like Australia and most of the Middle East have poor internet connectivity. South Korea has the fastest internet in the world, while North Korea is the only country in the world where less than 2% of the population has any access to the internet.