Today's internet

Aside from the complex physical connections that make up its infrastructure, the Internet is facilitated by bi- or multi-lateral commercial contracts (e.g., peering agreements), and by technical specifications or protocols that describe how to exchange data over the network. Indeed, the Internet is essentially defined by its interconnections and routing policies.

As of March 10, 2007, 1.114 billion people use the Internet according to Internet World Stats.

Internet protocols

For more details on this topic, see Internet Protocols.

In this context, there are three layers of protocols:

• At the lowest level is IP (Internet Protocol), which defines the datagrams or packets that carry blocks of data from one node to another. The vast majority of today's Internet uses version four of the IP protocol (i.e. IPv4), and although IPv6 is standardized, it exists only as "islands" of connectivity, and there are many ISPs without any IPv6 connectivity. [1]
• Next came TCP (Transmission Control Protocol), UDP (User Datagram Protocol), and ICMP (Internet Control Message Protocol) - the protocols by which data is transmitted. TCP makes a virtual 'connection', which gives some level of guarantee of reliability. UDP is a best-effort, connectionless transport, in which data packets that are lost in transit will not be re-sent. ICMP is connectionless, it is used for control and signaling purposes.
• On top comes the application protocols. This defines the specific messages and data formats sent and understood by the applications running at each end of the communication.

Internet structure

There have been many analyses of the Internet and its structure. For example, it has been determined that the Internet IP routing structure and hypertext links of the World Wide Web are examples of scale-free networks.

Similar to the way the commercial Internet providers connect via Internet exchange points, research networks tend to interconnect into large subnetworks such as:

• GEANT
• GLORIAD
• Abilene Network
• JANET (the UK's Joint Academic Network aka UKERNA)

These in turn are built around relatively smaller networks. See also the list of academic computer network organizations

In network schematic diagrams, the Internet is often represented by a cloud symbol, into and out of which network communications can pass.

ICANN

For more details on this topic, see ICANN.

The Internet Corporation for Assigned Names and Numbers (ICANN) is the authority that coordinates the assignment of unique identifiers on the Internet, including domain names, Internet Protocol (IP) addresses, and protocol port and parameter numbers. A globally unified namespace (i.e., a system of names in which there is one and only one holder of each name) is essential for the Internet to function. ICANN is headquartered in Marina del Rey, California, but is overseen by an international board of directors drawn from across the Internet technical, business, academic, and non-commercial communities. The US government continues to have the primary role in approving changes to the root zone file that lies at the heart of the domain name system. Because the Internet is a distributed network comprising many voluntarily interconnected networks, the Internet, as such, has no governing body. ICANN's role in coordinating the assignment of unique identifiers distinguishes it as perhaps the only central coordinating body on the global Internet, but the scope of its authority extends only to the Internet's systems of domain names, IP addresses, and protocol port and parameter numbers.

On November 16, 2005, the World Summit on the Information Society, held in Tunis, established the Internet Governance Forum (IGF) to discuss Internet-related issues.

Language

For more details on this topic, see English on the Internet.

The prevalent language for communication on the Internet is English. This may be a result of the Internet's origins, as well as English's role as the lingua franca. It may also be related to the poor capability of early computers to handle characters other than those in the basic Latin alphabet.

Further information: Unicode

After English (30% of Web visitors) the most-requested languages on the World Wide Web are Chinese 14%, Japanese 8%, Spanish 8%, German 5%, French 5%, Portuguese 3.5%, Korean 3%, Italian 3% and Arabic 2.5% (from Internet World Stats, updated January 11, 2007).

By continent, 36% of the world's Internet users are based in Asia, 29% in Europe, and 21% in North America ([2] updated January 11, 2007).

The Internet's technologies have developed enough in recent years that good facilities are available for development and communication in most widely used languages. However, some glitches such as mojibake (incorrect display of foreign language characters, also known as krakozyabry) still remain.

Internet and the workplace

The Internet is allowing greater flexibility in working hours and location, especially with the spread of unmetered high-speed connections and Web applications.

The mobile Internet

The Internet can now be accessed virtually anywhere by numerous means. Mobile phones, datacards, handheld game consoles and cellular routers allow users to connect to the Internet from anywhere there is a cellular network supporting that device's technology.