Change IP based on AP

Windows allows you to fallback to an alternative Static IP, which is covered in this related question:

Is it possible to configure a static IP alternative for all adapters using the registry?

If you configure each AP to use Automatic Private IP Addressing, then multiple access points can be configured to automatically assign IP addresses without DHCP:

The Internet Assigned Numbers Authority (IANA) has reserved 169.254.0.0-169.254.255.255 for Automatic Private IP Addressing. As a result, APIPA provides an address that is guaranteed not to conflict with routable addresses.

After the network adapter has been assigned an IP address, the computer can use TCP/IP to communicate with any other computer that is connected to the same LAN and that is also configured for APIPA or has the IP address manually set to the 169.254.x.y (where x.y is the client’s unique identifier) address range with a subnet mask of 255.255.0.0. Note that the computer cannot communicate with computers on other subnets, or with computers that do not use automatic private IP addressing. Automatic private IP addressing is enabled by default.

You may want to disable it in any of the following cases:

- Your network uses routers.

- Your network is connected to the Internet without a NAT or proxy server.

Unless you have disabled DHCP-related messages, DHCP messages provide you with notification when you change between DHCP addressing and automatic private IP addressing. If DHCP messaging is accidentally disabled, you can turn the DHCP messages back on by changing the value of the PopupFlag value in the following registry key from 00 to 01:

HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\VxD\DHCP

OSX allows mixing local and remote access points as well via link-local addressing.

References

Dynamic Configuration of IPv4 Link-Local Addresses

IPv6 Address Types

Mixing link-local IP addresses and routable IP addresses

Zero Configuration Networking

Airport: About Using Link-Local Addressing

Service Publication: An Example

Paul Sweatte

Posted 2011-09-19T14:55:56.743

Reputation: 613

Wireless networks not running DHCP? Now, that's odd. – Iszi – 2011-09-19T15:05:37.310

2For this, I think DHCP is the "standard method or service that people commonly use". :-( – RedGrittyBrick – 2011-09-19T15:07:11.470

If it's only one SSID and multiple locations, the only solution I see is a batch file/powershell script that checks BSSID and sets the IP manually. And yes, DHCP is the way to get that functionality. – RobotHumans – 2011-09-20T14:34:01.400

Have you looked at this post? http://superuser.com/questions/77132/static-ip-addr-for-just-a-particular-access-point-in-vista

– CharlieRB – 2011-10-11T20:17:37.443

Change IP based on AP

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