How do I access my PC via DHCP?

Question

I am going to move to a new place and am considering applying for a dsl line there.

I saw most DSL services use DHCP to assign an IP address to a computer (static IP addresses are more expensive). How stable is the assigned address? I mean, how often does the DHCP server change the assignments?

I want to access (using ssh) my linux box (at home, connected by DSL) from school. I can check the IP address before I leave home, but if the IP address changes while I am at school, there seems to be no way I can access my computer again until I find the newly assigned IP address. Is it possible to assign a name to my computer, for example, myPC.att.com so that I can access it regardless of the IP address?

Any advice is appreciated.

Answer 1

I have Cox high-speed at college and the IP never changes unless the modem is off for 24 hours...my parents have FiOS and the IP changes every week or so.

There are free Dynamic DNS services such as http://www.dyndns.com/ that let you install a 'client' on your computer and it lets you access your computer with something like bob.dyndns.org

Here are the hostnames DynDns has...

http://www.dyndns.com/services/dns/dyndn...

The info about their service...

http://www.dyndns.com/services/dns/dyndn...

And DynDns update client downloads...

http://www.dyndns.com/support/clients/

Answer 2

Use No-IP or DynDNS - they're both free services.  The computer runs a little program that checks the IP every 5 minutes or so and, if it changes, reports the new one to the service.  You connect to a named address you get when you sign up for the service, and it does a redirect to your IP.

I've been using No-IP for a few years.  Aside from the fact that you now have to confirm usage every couple of months (a minor inconvenience), it's nice.  I can access the home network from anywhere in the world when I need to.

I've held an IP address for months, and I've disconnected, reconnected within seconds and gotten a new one.  But with dynamic DNS service, who cares?