Whilst surfing at my leisure this evenin’, I got to wondering: With all of the “dot coms, orgs, nets” and so forth, is there really any limitation on what can be used as an address outside of international agreement? For example, can I start up a website addressed as ‘www.cecilrules.sdmb’?
For that matter, can I begin a public webpage with any prefix I like, such as “cecil.adams.sdmb”?
Tripler
Just curious. . .
I believe that it is IANA (http://www.iana.org/) who decide what domain names are allowed to be used and by whom, but what they can enforce is a different issue.
I don’t think its a tech issue, but a control issue…
Grim
ICANN, the Internet Corporation for Assigned Names and Numbers, controls the list of top level domains (TLDs).
Technically speaking, there’s no reason you can’t start up your own name server and put whatever domains in it you like - but no one else on the internet will be able to use them.
Yes, as long as you don’t use any crazy punctuation. In fact, you’re using boards.straightdope.com right now.
Basically, DNS (domain name service) consists of a hierarchy of servers. When you’re looking up a hostname, say boards.straightdope.com, you first go to a root server managed by ICANN and ask it about “.com”. The root server directs you to another server, and you ask it about “straightdope.com”. That server directs you to the Chicago Reader’s name server, and you ask it about “boards.straightdope.com”, and this time you get an answer. The Reader can change the “boards” part, but they can’t do anything about the “.com” part, because that part of the name has already been resolved by the time the question gets to them.
If you wanted to start up your own TLD, it wouldn’t be impossible, but it’d mean running your own root servers and convincing the rest of the world to use them instead of ICANN’s.
First off, there are characters that would be illegal in a URL and would cause a name to be unable to resolve, such as spaces, newline, tab and other control characters.
Barring that, one cannot just create a new top-level (ie: com, net, org, uk, etc…) domain for public use. Briefly put, resolving a DNS name to an IP address is a multisteped process that starts with whatever is to the right of the last period and moves to the left. For example:
I want to go to www.straightdope.com. When I type that in, my browser needs to know (behind the scenes) what IP address www.straightdope.com resolves to. It will first send a DNS query to one of the many root servers, asking for the address of a server authoritative for .com. It will then go to one of those .com servers asking for a server authoritative for straightdope.com. It will then go to one of those servers asking for www.straightdope.com. (Note: These can be cached on your computer or local DNS server, saving a few steps.)
The point being, if you wanted to create a .smdb top-level domain, nobody would be able to get to it, since the root DNS servers wouldn’t know where to direct anyone looking for a .smdb authoritative server. This is where ICANN comes in, running the root servers which contain a list of all DNS server for top-level domains - if they don’t list you, it’s not gonna happen.
Of course, you could set this up on your personal DNS server and point your friends to it, but the general public won’t be able to get to any .smdb servers.
As for the second part, you can create a DNS record for any server you want to the left of the domain. For instance, this site is boards.straightdope.com. It’s as simple as adding a record boards. on the DNS server which controls straightdope.com. It could have easily been cecil., tripler., or chicagoreader.
On preview, I’ve been beaten.
Well, this leads me to this question: the ICANN runs all of the root level servers (meaning all Internet traffic goes through these servers)? I mean, what if say, SeaLand [sub]yeah, that one[/sub] wanted to start it’s own ‘.sl’, assuming it’s not already taken of course. . . It would have to convince the rest of the world (through the ICANN) to recognize it’s particular DNS server as the root to the ‘.sl’ domain?
It seems like the ICANN root servers are a critical bottleneck in the whole thing. If the server(s) go down, then the whole Internet is broken, right? [sub]I’m assuming there’s redundant servers around. . .[/sub]
http://much.obliged.trip
:dubious:
The root servers are a bottleneck, yes. If they all went down, the majority of public internet traffic would cease - the internet wouldn’t be broken, but most people typing addresses into IE, Safari, etc wouldn’t get a damn thing. Likewise, email would stop. However, you could still get to internet resources by thier IP address, provided you knew it or at least wrote it down (assuming the core routers were still running). Of course, private networks would still work if configured properly.
Of course, ICANN recognizes this and takes steps to prevent it. If you recall the DDoS attack in October 2002, all root servers were attacked and some taken down; despite that, most people were unaffected. In light of that attack and 9/11, ICANN has seriously secured their buildings and separated redundant servers - some used to sit next to each other, now they’re all in separate facilities. (Article about the November 2002 server move) Those site are highly secure, hard to find and have plenty of redundant power and network connections.
Likewise, while many of the root servers are in the US, there’s a site in Japan, the UK and I believe Sweden. (This info may be out of date.)
The root servers are a bottleneck, yes. If they all went down, the majority of public internet traffic would cease - the internet wouldn’t be broken, but most people typing addresses into IE, Safari, etc wouldn’t get a damn thing. Likewise, email would stop. However, you could still get to internet resources by thier IP address, provided you knew it or at least wrote it down (assuming the core routers were still running). Of course, private networks would still work if configured properly.
Of course, ICANN recognizes this and takes steps to prevent it. If you recall the DDoS attack in October 2002, all root servers were attacked and some taken down; despite that, most people were unaffected. In light of that attack and 9/11, ICANN has seriously secured their buildings and separated redundant servers - some used to sit next to each other, now they’re all in separate facilities. (Article about the November 2002 server move) Those site are highly secure, hard to find and have plenty of redundant power and network connections.
Likewise, while many of the root servers are in the US, there’s a site in Japan, the UK and I believe Sweden. (This info may be out of date.)
Apparently my info on the locations of the root servers is sorely out of date.
www.root-servers.org lists the locations of the servers: F is on 6 continents, I on 5, J and K on 4, and M on 2.
And to further expand on your original question, there’s really no limit to anything that comes to the left of the .com/.net/etc. I could really have a website http://cecil.is.the.king.of.the.world.and.shall.inherit.the.earth.straightdope.com
One would need only to have a directory for each for each of those subdomains on the straightdope.com DNS server (or spread them onto multiple servers, whatever).
That example is of course exagerated, but subdomains can be useful to separate departments or offices. For example ICANN uses them to give each committee a separate subdomain:
Address Supporting Organization (ASO) - <www.aso.icann.org>
Country Code Domain Name Supporting Organization (CCNSO) - <www.ccnso.icann.org>
Generic Names Supporting Organization (GNSO) - <www.gnso.icann.org>
At-Large Advisory Committee - <www.alac.icann.org>
Governmental Advisory Committee - <www.gac.icann.org>
There have been several (essentially failed) attempts to start additional independent TLDs. It is really quite easy. Set up your own DNS servers and distribute software that merely adds an additional DNS server to your machine’s existing list. (Actually, with most machines using DHCP nowadays, there has to be actually running software on the machine.) There was one such company that managed to almost thrive for several years and had partnered with some major players to distribute the software. But the partners gave up and now the company works with spyware companies to distribute its software. Ouch.
Here’s some info on alt_dns.
More recently, there was a slashdot article about China starting their own TLD system which is more than likely going to happen.