Internetworkers: http://www.ibiblio.org/internetworkers/

[Steven Champeon <schampeo AT hesketh.com>]

on Tue, Sep 09, 2003 at 08:20:00PM -0400, Ken Pugh wrote:
> Does anyone know what IP address range public wireless networks use as a 
> default?  I'm wondering if they tend to use the same as my home/office 
> network.  If so, then I might change my home network, since I allow some 
> stuff to get through TPF that I normally wouldn't allow from the outside 
> world.

There are only three IP netblocks reserved for private (e.g., non-public
Internet) use, which is usually what you get if you're on a wireless
network configured for NAT:

     RESERVED-10 / IANA-ABLK-RESERVED1       
        10.0.0.0/8      - RFC 1918  -  LAN ONLY

     IANA-BBLK-RESERVED / IANA-BBLK-RESERVED1
        172.16.0.0/12   - RFC 1918  -  LAN ONLY

     IANA-CBLK1 / IANA-CBLK-RESERVED1
        192.168.0.0/16  - RFC 1918  -  LAN ONLY

DHCP clients that can't get a live IP default into this range:

     LINKLOCAL
        169.254.0.0/16  - autoproxy - Client-to-Gateway ONLY

The easiest way to avoid getting cracked on a public wireless network
is not to run vulnerable services when on an untrusted network.

Steve

-- 
hesketh.com/inc. v: (919) 834-2552 f: (919) 834-2554 w: http://hesketh.com
Book publishing is second only to furniture delivery in slowness. -b. schneier