Internet Addresses
Uniform resource locators (URLs) such as www.Yahoo.com represent addresses for sites on the World Wide Web. The Internet protocol, the system for addressing Internet packets, translates URLs to 32-bit IP addresses (e.g., 123.444.52.323) so they can be routed to their destination. To avoid duplication, most of the URLs are administered by central organizations.
The international Internet Corporation for Assigned Names & Numbers (ICANN) is an international nonprofit organization created by the United States government in 1998 to oversee Internet naming and numbering matters. ICANN appoints organizations to assign and keep track of URLs and approves the creation of new top-level domain names. Top-level domain names can be generic such as .com or country-specific such as .uk for the United Kingdom. ICANN approves companies to be registries and registrars.
Registries manage the entire database for a top-level domain name such as. org. They may also sell domain names to end users. There is only one registry per top-level domain name.
Registrars sell domain names to end-user customers. However, they don't manage the database for all of a particular top-level domain name. There are many registrars for each top-level domain name.
Registries—Management of Entire Top-Level Domains
Registries keep track of and manage databases of URLs. VeriSign manages the registry of top-level domain names .com, .net and .org. It operates the shared registration system (SRS), a database of .com, .net, .org, .tv, .bz, .nu and .cc top-level domain names. For example, if an organization or individual requests a particular domain name, the registrar checks the SRS for availability. The SRS contains information about networks, domain names and the contacts for each domain name. VeriSign's .net registry agreement with the U.S. Department of Commerce expires June 30, 2005. It will divest its .org registry in 2002 after which time ICANN will assign a nonprofit organization as the registry.
ICANN has assigned the rights to keep registries of names in the following new top-level domains:
.edu to EDUCAUSE
.biz to NeuLevel
.name to Global Name Registry Ltd. (GNR) in London
.info to Affilias, LLC
Registry companies are trying to avoid disputes about trademarked organization names.
Registrars
Companies called registrars have been approved by ICANN to buy banks of names at a discount from registry organizations. One hundred forty-eight companies worldwide are accredited to date as registrars. Registrars are responsible for gathering the technical information on which each domain name they register is located. They pay fees of about $6 to companies such as VeriSign and NeuLevel for each address they assign within a domain. Customers pay an annual fee to registrars to keep their domain registration up to date.
VeriSign is both a registrar and a registry. The Department of Commerce audits VeriSign to ensure fair treatment of registrars by VeriSign. It requires that VeriSign operate its own registrar service that it provides to end users separately from the service it provides to other registrars.
Numeric IP Addresses
Numeric IP addresses are assigned separately from URLs. ISPs and other organizations are assigned numeric IP addresses by registry bodies such as American Registry for Internet Numbers (ARIN), which assigns numbers in North and South America, the Caribbean and sub-Saharan Africa. ISPs keep lists of IP addresses that they use to route traffic to their customers that is not directed to a customer's domain name ([email protected]). Asia Pacific Network Information Center (APNIC) and Reseaux IP Europeens (RIPE) manage numeric IP addresses for Asia and Europe, respectively.
The Structure of Internet Addresses and Adding Capacity for More Addresses
Email addresses demonstrate the structure of IP addresses. To the left of the @ sign is the user's name. For example, JohnDoe@. To the right of the @ sign is the domain name. The domain name is the name of the computer at which the email address is located. Corporations use their name or an abbreviated form of their name for their domain name. To the right of the computer or organizational name is a description of the type of organization using the address. This is a top-level domain. The following are six generic top-level domain names:
The current 32-bit IP addressing scheme has a capacity for 4 billion addresses. (A 32-bit code has 232 permutations.) There is concern that use of IP addresses for data-equipped wireless service will deplete the number of available addresses. In addition, demand for Internet addresses in countries such as Japan, India and China is expected to increase. Currently, North America has 74% of the world's IP addresses, Europe has 17% and Asia/Pacific has 9%. A total of 400 million public IP addresses are in use.[1] (Public IP addresses point to an organization. Private IP addresses specify particular users or devices within organizations.) A new 128-bit protocol, IPv6, has been approved that will greatly increase the number of available public Internet addresses. However, Internet equipment such as routers and servers need to be upgraded to work with Ipv6. Major manufacturers such as Cisco, Microsoft and Sun have announced plans or started to produce IPv6-compatible routers, servers and operating systems.
[1] These statistics were reported in the article, “Introducing a New Internet Protocol to Fix Traffic Problems Faces Criticism, Apathy,” published in The Wall Street Journal WSJ.com, 14 May 2001, by Dan Goodin.
New Generic Top-Level Domains (gTLDs)
Generic top-level domain (gTLD) names are not associated with a particular country or territory. ICANN, the Internet Corporation for Assigned Names and Numbers, which is responsible for approving new top-level domain addresses, has approved the following seven new generic top-level domain names.
.info— For information-based services such as newspapers, libraries, etc.
.pro— For professions such as law, medicine, accounting and so forth
Country Code Top-Level Domain Names (ccTLDs)
Countries outside of the U.S. use country-specific, geographic, top-level domain names referred to as country code top-level domain names (ccTLDs). For instance, .jp is for Japan, .cn is for China and .uk is for the United Kingdom. Sites may use generic domain names preceding the country code top-level domain (ccTLD) name. Country-specific top-level domain names are approved by ICANN in Latin character sets only. Many Asian countries have requested ICANN approval of top-level domain names in non-Latin characters as more of their populations acquire Internet connections. ICANN, however, usually follows Internet Engineering Task Force (IETF) recommendations, which has indicated it may soon set standards for non-Latin characters. VeriSign is testing the use of non-Latin characters.
Alternative Domain Naming Services
Some Asian countries are developing an alternative set of domain name servers in non-Latin characters. China has announced it is developing its own domain naming system. China states that it considers it its sovereign right to control domain names in Chinese characters. Because these names are in a different set of master directories, users must download special plug-in software with unique domain name system settings. The Chinese government has made free software available for routing traffic to its domain names. A Singapore-based company, iDNS Ltd., also has its own domain naming system.