ISP port blocking practice

Curtis Maurand cmaurand at xyonet.com
Fri Sep 3 12:44:42 CDT 2010


I use SSL only and even then, it requires authentication.

--Curtis



On 9/3/2010 1:00 PM, Owen DeLong wrote:
> I have had it happen in some metro areas on sprint. I have experienced it in at least a dozen hotels over the last 12 months. I have run into it in various airports with free public wifi. I have run into the problem in several coffee shops.
>
> By far, the worst offenders are the most expensive hotels where the Internet access, damaged as it is generally goes for $25+ per day. I almost always end up getting free Internet as a result because I report the issue as a problem and their technical support usually can't spell tcp let alone understand what I mean when I say a port is blocked.
>
> Even worse is the ones that silently redirect your smtp (regardless of port) session to their MTA. Fortunately, my configuration is good enough that it just breaks in these cases, but I know many people who thought they were connecting to their own server via TLS only to later discover that their mail was relayed in clear text through several third party servers. (most mua's seem to have an unfortunate default to "ssl or tis if available" and keep right on sending even if tis negotiations are rejected.)
>
> Owen
>
>
> Sent from my iPad
>
> On Sep 4, 2010, at 12:08 AM, JC Dill<jcdill.lists at gmail.com>  wrote:





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