Random: Business Email DoS - Commercial Email Filters now automatically flag messages sent using a different server.

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Feb 10, 2021, 9:46:12 PM2/10/21
to 2600-australia
Stupidity Advisory:

This one is a little one -
A number of commercial email filters, including google now
by default too;  prohibit and flag all email not sent from
the same IP as the sender MX domain. Google in particular
specifically call these "illegal emails" now and actively
discriminate against this sort of email.

Obvisouly this was always an option in the past, but now it
is no longer optional.

Why is this a problem?
Many small organisations use shared hosting or off site
domain and email hosts.     For a variety of reasons due to
standard security configurations, or simply to speed up
outbound email transmission times these organisations cannot
use their email provider for outbound mail  - their ISP may
block it as standard (as is the case in the entirety of xtra
NZ) or the organisation may have multiple mailboxes or
domains, and their mail client (example thunderbird)
defaults to a single outgoing server; which would reject
relay on all messages but the mailbox matching its security

As a result many organisations utilize their ISP's outbound
server, a situation that most ISP's happily cater for - or
install their own in-house local relay server .  In the past
this has worked well for many.  Attachments in particular
will upload faster to a local outbound mail server this way.

This however has resulted in an accidental "DoS" situation
where many of these organisations can now no longer conduct
business with email - all messages sent in this scenario
will immediately be classified as junk/trash and never seen
by the recipient if they use any of the google or similar
commercial mail filters.

With the possible exception of those using their ISP's
internal email address (something which is a stupid idea
given how many online services use email as a form of
identity confirmation, and anyone changing ISP's will
immediately lose their mailbox)   this means a large part,
and possibly the entirely of NZ business's will now no
longer be able to contact a large percentage of the world
using email anymore, and small organisations will likewise
need to telephone or otherwise notify associates to check
their spam folder any time they send an email.  Clearly an
absurd situation for google and the similar commercial
filtering services to have caused.


New and improved 2600... well.. ..we drew on some flames and polished it a bit..
Google - making sure, life is no more, than 1984...
Bill Gates: 640k is more than enough for anybody
PC guy down the road: You will never fill that 10mb Hard disk mate
Abbott/Turnbull: 25Mbps is "more than enough" for the average Australian household.
Turnbull: Actually 10MBs is enough for the average household really.
Abbott/Turnbull: It is cheaper to put in FTTN, you get up to 24mbs/down and 256k up.. we can upgrade it more later...

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