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Mobile IP and Networking Services: Answers to Frequently Asked Questions
OIT's Mobile Networking Services: Answers to Frequently Asked Questions (FAQ)


OIT Mobile Networking Services allows you to temporarily attach your computer to OIT Ethernet or Wireless networking services on a network other than your "home network." You can continue to receive network services without reconfiguring your computer or updating its Host Database entry.

What is my home network?
To find out which subnet a computer should be registered in, or what subnet an office is in, see the Princeton Network ("subnet") List at:

To obtain Mobile Services, a computer must be registered in the Hostmaster Database. Please see:

Is my computer blocked from the network?
A device that is misconfigured in such a way as to cause it to not meet the requirements for OIT DHCP service (described in the document DHCP and BootP Services) may be declared Ineligible for OIT Mobile IP Service. This is typically done when the computer's misconfiguration causes it to interfere with other customers of the service, or with the service as a whole. A list of devices that have been declared ineligible appears in Devices Blocked from Mobile IP Service.

The most common misconfiguration of this sort is to run more than one DHCP client instance (per hardware address). Often this does not interfere with service when the device is attached to its home network, but only becomes apparent when the device visits another network and uses OIT Mobile IP Service.

Why have I received an e-mail from OIT regarding my home network?
Your Host Database entry is the registration record of your computer on the Princeton network. It should be kept accurate, by you, as the technical contact of your computer. You can also assign others to be technical contacts, if you wish, to give them this task. Review your entry at to make sure information about your computer and your home network are correct.

If your computer "camps" on another network for an extended period of time and appears to OIT as remaining there, your Host Database entry will be automatically updated and you will be notified by e-mail. When your home network has been changed, you will need to re-start your computer to avoid network interruption. You should also take this opportunity to make sure your building and room number information is updated in the Host Dabase as well. See Mobile IP Campers for more information.

Where can I find more information?
Because of the special demands associated with mobile computing, there are some guidelines you'll need to be particularly aware of. Those guidelines are covered at:

Last Updated:
February 10, 2005

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