US Provisioned GSM cards abroad... SSL Issues?

William Waites ww at
Thu Nov 15 21:15:59 UTC 2007

On Wed, Nov 14, 2007 at 06:18:17PM +0000, Steven M. Bellovin wrote:
> "Mike Lyon" <mike.lyon at> wrote:
> > 
> > Curious. Has anyone on the list here ever encountered issues while
> > traveling in EMEA accessing SSL websites back in the states while
> > using an ATT/Cingular GSM data card? We are seeing some issues with
> > this and were curious to see if anyone else is seeing the same issue.
> > 
> Do you have a tcptraceroute?  Might some "helpful", "transparent" proxy
> be getting in your way?  (You don't say anything about what your issues
> are.)

Such broken "transparent" proxies seem to be very common on GSM carrier's
data networks. I've even recently seen problems that look like a re-direct
loop without ever really hitting the server, with a pre-paid SIM from
Yoigo (a Spanish carrier). Mind you, this was a complex SSL setup involving
client-side certificates, and "normal" SSL sites.

Solution: set up a "good" squid proxy somewhere, perhaps on an uncommon port,
to bypass the "evil" proxy.

Next problem: empty bank account when the roaming charges come home ;)


More information about the NANOG mailing list