Re: can not ssh from certain isp's

From: Greg Pratt (usenet@gp.users.panix.com)
Date: 03/27/03 

From: usenet@gp.users.panix.com (Greg Pratt)
Date: 26 Mar 2003 22:01:00 -0500

In article <3e80180c@news.alphalink.com.au>, huw <huwgo41@hotmail.com> wrote:
>Since early 2002 I have been unable to ssh from my main isp (Alphalink
>australia) to the australian national university and vice versa. However I
>have no such problems when using ssh from my eisa dynamite work isp. The
>university does not require keys or anything like that and there seems to be
>no reason why one isp should be able to connect flawlessly while another
>times out before the login screen appears..
>
>running a traceroute from the university shows that the packet never leaves
>the local network.

That doesn't mean much; many sites have firewalls that eat ICMP packets
so that people can't snop around on their networks, especially from the
outside. (Some disable it from inside, too.)

>I have tried to connect to the ANU via alphalinks own ssh server as well but
>no such luck.
>
>If anyone has any ideas as to why one isp would be blocked while another
>works fine I am all ears. (btw I have done some checking. no other aussie
>isp seems to have any trouble using ssh to connect to the university.

The problem ISP may have misconfigured its firewall; I've been to hotels
with high-speed Internet access which disallow anything but web and
telnet (!) traffic. Or, your ISP may be blocking SSH traffic on
purpose, thinking that it's a security leak. In any case, it's probably
ignorance (accidental or wilful) that has lead to your ISP blocking ssh
connections. 

-- 
Gregory Pratt                                  usenet@gp.users.panix.com
East Rutherford, NJ, USA
PGP Key Fingerprint:  DC60 FCDE 91E2 3D41 91A3  45DB B474 3D3A 3621 AAFE

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