Domain Name Format

The domain name structure and domain name system were developed to organise and find the ip addresses of computers on large distributed networks.

Domain name format. Because their rdata format is known all domain names in the rdata section of these rrs may be compressed. Character string is a single length octet followed by that number of characters. Interchangeable upper and lower case letters is only true for the actual domain name.

Before the domain name structure was developed computer names and ip addresses were mapped using a flat list and stored in a simple text file called the hosts file. Second level domains aren t quite so restricted you can have pretty much whatever you like under com org or net although typically each country has its own version of com org and net and the actual domain lives under that the uk has co uk and org uk for example previous next. Specifies the name of the domain used to authenticate an account.

Additionally the domain name system is not case sensitive so you can register and write your domain name with both lowercase and uppercase letters. Below these top level domains in the dns hierarchy are the second level and third level domain names that are typically open for reservation by end users who wish. Although no technical limitation exists to use any character in domain name labels which are representable by an octet hostnames use a preferred format and character set.

Formatting internationalized domain names formatting domain names for domain name registration for domain name registration a domain name can contain only the characters a z 0 9 and hyphen. Domain name is a string. The domain name should between 1 and 63 characters long last tld must be at least two characters and a maximum of 6 characters the domain name should not start or end with hyphen e g.

You can t specify a hyphen at the beginning or end of a label. If a value for domain is not specified username must use the user principal name upn format user fully qualified dns domain netbios domain username format. When spelling things out in a url the names of folders and files can be case sensitive.

The value may be either a fully qualified dns domain name or a netbios domain name. Character string is treated as binary. Domain names are organized in subordinate levels subdomains of the dns root domain which is nameless.