Thank you, Comcast.

Mikeal Clark mikeal.clark at gmail.com
Fri Feb 26 06:36:07 UTC 2016


Totally agree.  It's silly that my home lab has to cost me 5x the
normal rate if I want to use some of the standard ports but that is
normal now.

On Fri, Feb 26, 2016 at 12:27 AM, Mark Andrews <marka at isc.org> wrote:
>
> In message <alpine.DEB.2.02.1602260718460.11524 at uplift.swm.pp.se>, Mikael Abrah
> amsson writes:
>> On Thu, 25 Feb 2016, Jared Mauch wrote:
>>
>> > Make sure you permit TCP/53 for DNS queries so if TC=1 lookups work.
>>
>> Speaking of which, historically ISPs have been blocking TCP/135, TCP/445
>> and a few others towards customers (at least that's what I know). TCP/25
>> seems to be blocked as well.
>>
>> Why isn't UDP/53 blocked towards customers? I know historically there were
>> resolvers that used UDP/53 as source port for queries, but is this the
>> case nowadays?
>>
>> I know providers that have blocked UDP/53 towards customers as a
>> countermeasure to the amplification attacks. As far as I heard, there were
>> no customer complaints.
>
> Because complaining is like talking to a brick wall most of the
> time.  People work around the ISP idiocy by shifting ports, its
> easier than trying to get through help desk hell.
>
>> --
>> Mikael Abrahamsson    email: swmike at swm.pp.se
> --
> Mark Andrews, ISC
> 1 Seymour St., Dundas Valley, NSW 2117, Australia
> PHONE: +61 2 9871 4742                 INTERNET: marka at isc.org


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