Re: 172.16.x.x routable?

From: Volker Birk (bumens_at_dingens.org)
Date: 10/15/05 

Date: 15 Oct 2005 13:25:03 +0200

null <null@null.null> wrote:
> I was under the impression that 172.16.x.x-172.31.x.x addresses were
> used for private ip addresses like the 192.168.x.x addresses are.

Yes, see RFC 3330. To be exactly: 172.16.0.0/12 is set aside for use in
private networks.

> I
> also thought that meant they're not routable.

Oh, they're routable. One should not route them to the Internet, though.

> The other day while I was
> helping someone they pinged me and the return address on their packets
> was 172.16.x.x. They were several hundred miles away so their packets
> had to get routed through a number of hops before it got to me. Can
> someone explain why this worked? Thanks.

Please post a traceroute.

Yours,
VB. 

-- 
"Ich bin ein freier Mensch und werde jetzt von meinen Freiheitsrechten
Gebrauch machen - und zwar ausgiebig - natürlich nur in dem Rahmen, den
Otto Schily mir noch zur Verfügung stellt."
                   Wolfgang Clement am 10.10.05 als Noch-Superminister

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