Does it start with 10.x.x.x, 192.168.x.x or 172.16-31.x.x ?? If so then its rfc1918.. Ie private IPs
If it starts with pretty much anything else its public ;)
See my wan is a public IP.. If you look up 24.13 its owned by comcast..
http://lmgtfy.com/?q=rfc1918
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