The Domain Name System ( DNS ) has a tree structure or hierarchy, with each non-RR ( resource record ) node on the tree being a domain name. A subdomain is a domain that is part of a larger domain; the only domain that is not also a subdomain is the root domain.For example, west.example.com and east.example.com are subdomains of the example.com domain, which in turn is a subdomain of the com top-level domain ( TLD ). A “subdomain” expresses relative dependence, not absolute dependence: for example, wikipedia.org comprises a subdomain of the org domain, and en.wikipedia.org comprises a subdomain of the domain wikipedia.org. In theory this subdivision can go 127 levels deep ( though that limit is not in any published RFC ). Per RFC 1035, each DNS label can contain up to 63 characters, as long as the whole domain name does not exceed a total length of 255 characters, but in practice most domain registries limit at 253 characters.
Subdomains in this context are defined by editing the DNS zone file pertaining to the parent domain. However, there is an ongoing debate over the use of the term “subdomain” when referring to names which map to the Address record A ( host ) and various other types of zone records which may map to any public IP address destination and any type of server. Certain groups insist that it is inappropriate to use the term “subdomain” to refer to any mapping other than that provided by zone NS ( name server ) records and any server-destination other than that of a domain name server. Notwithstanding the terminology debate, many well-known public DNS providers use the term “subdomain” to refer to names which map to A ( host ) records which may map to any type of host or destination-server. Edited by Ariasun editorial board
Web site ariasuniweb net AriasuniPortal ariasuni Health Journal Family physician Medical Health </ em> Ariasan Elcomp </ em> Elcomp Exhibition </ em> Online Elcomp </ em> Therapy Health Electronics Tourism Aryans City Net Soocom Ariasun Soopak Ariasun medipharma Advertisement Reader The requirements Employment Currency Exchange Currency Coin Gold < em> car property land building stock exchange bank Government People Leader Assembly Quran Book Student University Knowledge base Exercise Sima Sound Religion < / em> Life People Hope Work Dread Unemployment youth exercise information technology computer < / em> Hardware Software Computer Server Virtual Tablet < / em> Mobile Zanjan Tehran Iran Germany Greece Georgia Georgia Dubai World Air Space < em> Country Product Finder AriaSun International Group Online Store WikiPharma AriaSun Production Industrial Operations Equip Installation & Investment Air Space International Trading Research Industrial Business Medical Dummy Undoubtedly Health Drug Therapy Health Information Technology & Computer Airlines Tourism Logo Design Sticker Design Advertising Campaign Science & Research News </em > Political News Economic Trade International Stock Market News Medical Tourism & Cultural Heritage Aeronautics & Tourism Sport & Olympic Domain and University The Quran Arts & Culture Industry & Technology Accidents Ladies Currency and Gold Coins Flats Rip’s Web Site Kandasheh Ahwaz Web Site Foot Website Abuse Clean Sean Cinere Live Nature Whats Punababy Mussels Clinic Radarians Man AriaSun Preddies Reservations < Em> Tourists Unemployment youth exercise CityNet PakSaman SooComAriaSun SooPakAriaSun MediPharma AriaSun Kalayab AriaSunBazar AriaSunBazar Medeca MediKala Artists Group AriaSunGroup Web site designing RP Pilgrimage website Historical tours website Web Resident Resorts site Tours website The Pana The Natural Tours Website Kandesheh Ahwaz The Scientific Tour Website Oil & Refineries The Sports Tour Website Gas The Web Tours Water Exposure Tour Site Travel Tour Website Travel Tours The Last-minute Tours Site Tours of the last minute Web-site of the local tours Recreation site Internal tours site Pilgrimage Fun Places Design Web Design City Net Designing a Holiday Resort Pilgrimage Pilgrimage Website designing pilgrimage City Net Pilgrimage Travel </em > Designing Travel Planner Website Designing Travel Places Historic Places Designing Historic Places Historic Places Design Residences Residential Residential Design Residential Residential Design Cultural Places Designing a Web Site for Cultural Places Designing Cultural Places Natural Places Natural Places Designing a natural site Designing a natural website scientific Designing for scientific Designing for scientific sports sports designing sports < Em> Sports Facilities Design Sports Facilities Sport Sport Designing a Sports Center for Extreme Sports Creating places Designing for Exhibition Exhibit places Designing Exhibit Places Designing Exposure Website Web Recreation Recreation Web Design Recreational tours The design of the tourist resorts Pilgrimage Pilgrimage Pilgrimage Pilgrimage Pilgrimage Tours Historic Tours Tour Design Historic Tours Web Tour Design Historical Tours Residential Tours Resorts Tour Design Residential Tour Website Design Cultural Design Cultural Tour Site Cultural Tour Website Natural Designing Natural Tours Designing Natural Tours Web Site Science Designing Scientific Tours Designing Sci-Fi Web Site Designing a Sports Tour Designing a Sports Tour Website Designing a Tours Tour Designing a Touring Web Site Exhibit Exhibit Tour Travel Designing Tours Tour The Last Moment Toure The Last Moment Designing the Last Minute Tours Internal Tours Designing Local Tours Designing a Web Site Tour </em > Foreign Tours Designing a Tours Site Designing a Website for Tours Coastal Work < em> Designing the Coast Guided Tour Urban Designing Urban Tours Urban Touring Sights < Em> Sightseeing Design Sightseeing Web Site Mountaineering Sailing Designing Sailing Tours < Em> Website Designing Sailing Tours Aviation Designing Tours Cruising Cruising ships Creating cruise ship cruises Creating Cruise Cruises Inbound Flights Designing Inbound Flights Foreign Flights Designing a Foreign Airmail Web site Last Minute Flights Web Design Last Minute Deals cheap Website Design Cheap Flights Online Shopping Online Sales Online Selling Website Design Online Shopping Online Store Online Store Design Online Tickets Design an Online Ticket Internet Designing a Web Store Internet Tickets Designing an Internet Ticket parscoders