what's this unknowable IP then?

[#1]

Noticing some download activity just now, I ran tcpview only to find an established tcp connection  to 4.23.50.123 owned by svchost.exe
nslookup can't resolve that address ("non-existent domain") and it can't be pinged either
i'm presuming it's to do with ms update but my interest has been piqued as to why it's non-resolvable
ideas?

[#2]

http://samspade.org/whois/4.23.50.123

[#3]

mmm yes thanks chilly but it still doesn;t tell me the whats and whys !

[#4]

did you Google
A good answer here http://www.howtogeek.com/howto/windows-vista/what-is-svchostexe-and-why-is-it-running/

[#5]

it's not the svchost bit that i'm ignorant about pierre, I'm just puzzled by  the fact that there's an IP address that apparently doesn't resolve to anyhting that my compyter is connected to

[#6]

The only thing I can find is that it is on this list of ad servers http://pgl.yoyo.org/adservers/iplist.php so it may be serving up ad banners

[#7]

blimey thats' quite a list ...
ok thanks to all ... I think my curiosity is satisfied!
P