posted 13 years ago
To host a web application, all you need to do is connect a server to the Internet.
However, very few people can remember 216.199.14.18, so I also bought the domain name "mousetech.com" from a domain registration service. Then I set up 2 domain name servers (1 primary and 1 backup) and attached them to the Internet. A lot of people find this to be inconvenient, however, so you can pay someone else such as your ISP or registration service to do the domain name serving (DNS). All DNS is is just the Internet's equivalent of a telephone book for computers. Your browser wants to connect to my webserver, so it makes a DNS request for the IP address of www.mousetech.com. DNS responds with 216.199.14.18 and that's what your browser will plug into the destination address of its tcp/ip packets.
Note that there can be multiple servers in one domain. So my domain is "mousetech.com", but the fully-qualified domain name (FQDN) for my webserver is www.mousetech.com. As opposed to my mailserver, which is mail2.mousetech.com. The mail server is on a different machine with a different IP address, but that's just because I believe in spreading the load around.
So anyone can access my webserver using either the DNS name of www.mousetech.com or the ip address 216.199.14.18. But that's because I pay for a hosting account with my ISP, and a hosting account means specifically, that they permit me to host Internet services. A lot of home accounts, as I said before have legal restrictions against hosting (where available, their hosting products usually cost more).
In many cases, people can take advantage of the fact that the restriction is strictly in the contract and host anyway, although typically you have to use a special DNS service such as DynDNS that can track the server's IP address. That's because one of the things you pay for with a hosting contract is one or more fixed IP addresses. Home accounts usually have DHCP-assigned IP addresses, and the address assigned to your router may change periodically, such as once a week or whenever you power off your router, whichever comes first.
Some ISPs, however, don't just restrict host access in the contract, they restrict it physically. By putting up a firewall between your computer and the Internet that blocks Internet users from accessing your host ports (80 and 443, or whatever). In which case, you either need another contract or another ISP.
Education won't help those who are proudly and willfully ignorant. They'll literally rather die before changing.