[E-Mail] SMTP.rcn.com silently not relaying, again in RCN http://www.dslreports.com/forum/r20410623 en Sat, 26 Jul 2008 13:26:04 EDT Sat, 26 Jul 2008 13:26:04 EDT Re: [E-Mail] SMTP.rcn.com silently not relaying, again http://www.dslreports.com/forum/remark,20478103 dehmmy :
said by rcnman See Profile :

This is done in order to control outbound spam from zombies on the network. If you want to get around this block you can purchase a static IP that will open port 25.
Not to be rude but that is exactly what I said in my earlier post.

..............................
Why would a static ip open the port up when I can easily enable it in seconds.

** For purposes of protecting RCN and its policies, I will not discuss, reveal, or reply to any questions or inquiries regarding changing or modifying anything! **
...............................

I'm just making a silly point. Actually I really have no reason I'm just rambling cause I'm on my ADD medications.. please don't fault me for that.

=)

jay]]> http://www.dslreports.com/forum/remark,20478103 Tue, 13 May 2008 21:18:10 EDT Re: [E-Mail] SMTP.rcn.com silently not relaying, again http://www.dslreports.com/forum/remark,20477668 NormanS : Or read RFC 2476. That is the officially designated message submission port. Also, as a de facto standard, SMTPS (SMTP w/SSL) uses port 465.

Also read RFC 2821. SMTP does not require port 25, except for mail transfer.

If all E-mail Service Providers moved message submission to either the designated message submission port (RFC 2476), or even just any other port than port 25, it would be possible to reserve port 25 for mail transfer. Each gateway mail server can then decided for itself if a connecting mail host is trustworthy (allow), or not (deny).
--
Norman
~Oh Lord, why have you come
~To Konnyu, with the Lion and the Drum]]> http://www.dslreports.com/forum/remark,20477668 Tue, 13 May 2008 20:06:24 EDT Re: [E-Mail] SMTP.rcn.com silently not relaying, again http://www.dslreports.com/forum/remark,20476968 negativeduck : Several mail hosts will not accept unauthenticated delivery requests from hosts that are NOT known isp's, or rather they specifically 'reject' or do not allow communication from a host that "appears" to be a dynamic IP pool connecting to their mail exchangers.. now this is a different scenario than say 'smtp' servers while fundamentally they same they like to serve different purposes.

IE if you run your own mail-server on a standard dynamically allocated IP there is a strong chance that you will never be able to deliver your email to alot of hosts. This is where smart-hosting and smart-relaying come in where you transfer your mail to a larger ISP for delivery to another large entity.
--
Bryan Laird
Director Product and Technology]]> http://www.dslreports.com/forum/remark,20476968 Tue, 13 May 2008 17:45:10 EDT Re: [E-Mail] SMTP.rcn.com silently not relaying, again http://www.dslreports.com/forum/remark,20476884 jsolo1 : Norman good point. My response was based on email submission, not transmission. You do bring up a good point though. Not sure how that would work. I imagine there may be a white list of sorts?
--
Insanity is living in a state of disillusion.]]> http://www.dslreports.com/forum/remark,20476884 Tue, 13 May 2008 17:30:37 EDT Re: [E-Mail] SMTP.rcn.com silently not relaying, again http://www.dslreports.com/forum/remark,20476829 NormanS :
said by jsolo1 See Profile :

Perhaps if all servers required authentication, port 25 could be left open. No credentials, no smtp.
How would your email service relay agents move email if they were required to authenticate the connection? The basic idea is to separate message submission (which may require authentication) from mail transfer (which should not require authentication).
--
Norman
~Oh Lord, why have you come
~To Konnyu, with the Lion and the Drum]]> http://www.dslreports.com/forum/remark,20476829 Tue, 13 May 2008 17:22:15 EDT Re: [E-Mail] SMTP.rcn.com silently not relaying, again http://www.dslreports.com/forum/remark,20476594 negativeduck : You can infact relay mail from any mail-client as user@anydomain.com through smtp.rcn.com. Case by Case restrictions to this may be imposed as result of a compromised computer or host although in several of those cases enabling smtp auth will correct this.

If you are having a trouble sending email with your "From" setup as something other than rcn.com I would suggest enabling smtp auth and seeing if that helps with your problem.

We process a tone of email with customers doing just this scenerio so there is a possibility of specific 'one off' spam domains and what not. That being said if you want to message me some details around one of these 'dropped' emails we can research into where your mail is going.
--
Bryan Laird
Director Product and Technology]]> http://www.dslreports.com/forum/remark,20476594 Tue, 13 May 2008 16:34:45 EDT Re: [E-Mail] SMTP.rcn.com silently not relaying, again http://www.dslreports.com/forum/remark,20476329 jsolo1 : Perhaps if all servers required authentication, port 25 could be left open. No credentials, no smtp.
--
Insanity is living in a state of disillusion.]]> http://www.dslreports.com/forum/remark,20476329 Tue, 13 May 2008 15:43:03 EDT Re: [E-Mail] SMTP.rcn.com silently not relaying, again http://www.dslreports.com/forum/remark,20475911 NormanS :
said by rcnman See Profile :

This is done in order to control outbound spam from zombies on the network. If you want to get around this block you can purchase a static IP that will open port 25.
Or, if you are using a Gmail account, use either port 587, or port 465. RCN shouldn't be blocking those ports. You should be able to use *any* message submission server which listens on a proper message submission port. There is no law of nature, or Congress, which requires that message submission must use port 25.
--
Norman
~Oh Lord, why have you come
~To Konnyu, with the Lion and the Drum]]> http://www.dslreports.com/forum/remark,20475911 Tue, 13 May 2008 14:23:36 EDT Re: [E-Mail] SMTP.rcn.com silently not relaying, again http://www.dslreports.com/forum/remark,20475727 rcnman :
said by dehmmy See Profile :

said by NormanS See Profile :

said by dehmmy See Profile :

Yeah, they should at least have deep packet inspection to auto cut would be spammers instead of forcing you to use their smtp.. i agree
They aren't forcing you to use their SMTP server. They aren't blocking message submission ports; that I know of. It is just that, when using their SMTP server, they shouldn't care what your "From:" email address is.
Well, in my area at least they block all outgoing port 25 sessions unless it's to one of their smtp servers thus forcing you to use it and no one elses.

jay
This is done in order to control outbound spam from zombies on the network. If you want to get around this block you can purchase a static IP that will open port 25. ]]> http://www.dslreports.com/forum/remark,20475727 Tue, 13 May 2008 13:53:35 EDT Re: [E-Mail] SMTP.rcn.com silently not relaying, again http://www.dslreports.com/forum/remark,20474599 NormanS :
said by dehmmy See Profile :

Well, in my area at least they block all outgoing port 25 sessions unless it's to one of their smtp servers thus forcing you to use it and no one elses.
Unless they are also blocking ports 465 and 587, they are not preventing users from accessing any other mail servers.

I refer you to the list of mail servers I use, several posts up, none of which are blocked by blocking port 25.
--
Norman
~Oh Lord, why have you come
~To Konnyu, with the Lion and the Drum]]> http://www.dslreports.com/forum/remark,20474599 Tue, 13 May 2008 10:22:24 EDT Re: [E-Mail] SMTP.rcn.com silently not relaying, again http://www.dslreports.com/forum/remark,20473635 dehmmy :
said by NormanS See Profile :

said by dehmmy See Profile :

Yeah, they should at least have deep packet inspection to auto cut would be spammers instead of forcing you to use their smtp.. i agree
They aren't forcing you to use their SMTP server. They aren't blocking message submission ports; that I know of. It is just that, when using their SMTP server, they shouldn't care what your "From:" email address is.
Well, in my area at least they block all outgoing port 25 sessions unless it's to one of their smtp servers thus forcing you to use it and no one elses.

jay]]> http://www.dslreports.com/forum/remark,20473635 Tue, 13 May 2008 02:02:51 EDT Re: [E-Mail] SMTP.rcn.com silently not relaying, again http://www.dslreports.com/forum/remark,20468245 NormanS :
said by dehmmy See Profile :

Yeah, they should at least have deep packet inspection to auto cut would be spammers instead of forcing you to use their smtp.. i agree
They aren't forcing you to use their SMTP server. They aren't blocking message submission ports; that I know of. It is just that, when using their SMTP server, they shouldn't care what your "From:" email address is.
--
Norman
~Oh Lord, why have you come
~To Konnyu, with the Lion and the Drum]]> http://www.dslreports.com/forum/remark,20468245 Mon, 12 May 2008 02:51:28 EDT Re: [E-Mail] SMTP.rcn.com silently not relaying, again http://www.dslreports.com/forum/remark,20468179 dehmmy :
said by NormanS See Profile :

said by dehmmy See Profile :

said by kshakir See Profile :

You can hack around the port 25 restriction by using a third party server on another port...
Or you could input an invalid IP which you'd never send smtp to thus allowing outgoing port 25 (smtp) to any IP but I thought the first example was funnier.
Just trying to figure out how that would work.
just put in the Reply-To: line yourname@company.com which will tell the receiving party to reply to that address...
Not really a satisfactory solution. And a bunch of us, whose ISP gave us Yahoo! mail servers to use, are beating up both our ISP, and Yahoo!, over a similar restriction imposed by Yahoo!.
Yeah, they should at least have deep packet inspection to auto cut would be spammers instead of forcing you to use their smtp.. i agree

jay]]> http://www.dslreports.com/forum/remark,20468179 Mon, 12 May 2008 02:26:19 EDT Re: [E-Mail] SMTP.rcn.com silently not relaying, again http://www.dslreports.com/forum/remark,20465908 NormanS :
said by dehmmy See Profile :

said by kshakir See Profile :

You can hack around the port 25 restriction by using a third party server on another port...
Or you could input an invalid IP which you'd never send smtp to thus allowing outgoing port 25 (smtp) to any IP but I thought the first example was funnier.
Just trying to figure out how that would work.
just put in the Reply-To: line yourname@company.com which will tell the receiving party to reply to that address...
Not really a satisfactory solution. And a bunch of us, whose ISP gave us Yahoo! mail servers to use, are beating up both our ISP, and Yahoo!, over a similar restriction imposed by Yahoo!.
--
Norman
~Oh Lord, why have you come
~To Konnyu, with the Lion and the Drum]]> http://www.dslreports.com/forum/remark,20465908 Sun, 11 May 2008 15:44:10 EDT Re: [E-Mail] SMTP.rcn.com silently not relaying, again http://www.dslreports.com/forum/remark,20464366 dehmmy :
said by kshakir See Profile :

If you are using a configuration like the one below, you might want to check if people have actually been receiving your emails. Just ran some tests, and I'm pretty sure smtp.rcn.com is silently eating email again. No return-receipts, error messages, etc. I wonder where these messages are going...

Background:
- RCN blocks all outgoing SMTP (port 25) traffic, *except* to smtp.rcn.com. This means you cannot use smtp.yourcompany.com (port 25) to send email from home.
- You can hack around the port 25 restriction by using a third party server on another port, but this is NOT explained in the RCN help.
- Until a few days ago, you could send email from yourname@yourcomany.com using the RCN smtp server, even without login (great for visiting relatives), as long as you wer connecting from an RCN ip address.

What changed, smtp.rcn.com seems to:

- Still relay email if it comes From:
> any_user@rcn.com
> any_user@gmail.com (evidence of a whitelist??)
> (possible other whitelist domains I don't know)

- Silently NOT relaying message From:
> any_user@yourcompany.com
> any_user@yahoo.com
> any_user@( most domains ).com

Net result: If you work at home, you cannot use smtp.rcn.com, nor your own server, to send email for work, and are forced to sign up for a third party alternate-port server like gmail (here's to hoping you don't have certain customer email, which you might not want relayed through google ;)).

Anyone know how to report this? I spent hours the last time and got nowhere with the CSRs or sales departments. Posted here and it was fixed pretty quickly, so hoping someone is listening again!

(It'd be nice if RCN unblocked outgoing 25, but I understand that we're currently fighting a war on spam.)
Actually you can.. just put in the Reply-To: line yourname@company.com which will tell the receiving party to reply to that address

It's actually in one of the RCN FAQs

=0

jay]]> http://www.dslreports.com/forum/remark,20464366 Sun, 11 May 2008 06:25:51 EDT Re: [E-Mail] SMTP.rcn.com silently not relaying, again http://www.dslreports.com/forum/remark,20464356 dehmmy :
said by NormanS See Profile :

said by kshakir See Profile :

You can hack around the port 25 restriction by using a third party server on another port...
OR better yet. You could snmpwalk the modem changing only allow outgoing port 25 to RCN to deny all outgoing port 25 to RCN and allow all others. A 180 it would seem.

Or you could input an invalid IP which you'd never send smtp to thus allowing outgoing port 25 (smtp) to any IP but I thought the first example was funnier.

But like you have to be really really smart and it's really hard and I advise people to never EVER do that! ;p

In actuality, they just don't want people spamming.

=)

jay
]]> http://www.dslreports.com/forum/remark,20464356 Sun, 11 May 2008 06:11:25 EDT Re: [E-Mail] SMTP.rcn.com silently not relaying, again http://www.dslreports.com/forum/remark,20456437 NormanS :
said by kshakir See Profile :

You can hack around the port 25 restriction by using a third party server on another port...
I don't consider this a "Hack". RFC 2821 only defines port 25 for "Message Transfer"; moving email messages from MTA to MTA. It doesn't clearly define a method of "Message Submission".

RFC 2476 clearly defines "Message Submission", including defining port 587 as the official "Message Submission" port. In addition, port 465 has become a de facto standard for SMTP with Secure Sockets Layer (SSL). And party running an SMTP message submission server, and expecting access from users on any part of the Internet, needs to compensate for ISPs, such as AOL, AT&T, and Cox, which all (in addition to RCN) block outbound port 25 (and there are others; even Comcast, under certain conditions).

I occasionally use a few third party SMTP message submission servers (as well as two offered by my ISP):

mail.pacbell.net:587*
smtp.aim.com:587
smtp.aol.com:587
smtp.gmail.com:465 (w/SSL)
smtp.gmail.com:587 (w/STARTTLS)
smtp.gmx.com:587 (w/STARTTLS)
smtp.myrealbox.com:465 (w/SSL)
smtp.att.yahoo.com:465 (w/SSL)*
smtp.mail.yahoo.com:465 (w/SSL)
smtp.mail.yahoo.com.au:465 (w/SSL)
smtp.mail.yahoo.co.jp:465 (w/SSL)

(*) denotes my ISP mail servers.

There are some other third party email service providers which use some non-standard message submission ports, as well.
--
Norman
~Oh Lord, why have you come
~To Konnyu, with the Lion and the Drum]]> http://www.dslreports.com/forum/remark,20456437 Fri, 09 May 2008 11:13:12 EDT Re: [E-Mail] SMTP.rcn.com silently not relaying, again http://www.dslreports.com/forum/remark,20421091 rcnman : Indeed, he looked into it and whitelisted some of your domains. ]]> http://www.dslreports.com/forum/remark,20421091 Fri, 02 May 2008 12:25:07 EDT Re: [E-Mail] SMTP.rcn.com silently not relaying, again http://www.dslreports.com/forum/remark,20415294 kshakir : Email is being received again. Please forward my thanks!]]> http://www.dslreports.com/forum/remark,20415294 Thu, 01 May 2008 09:31:33 EDT Re: [E-Mail] SMTP.rcn.com silently not relaying, again http://www.dslreports.com/forum/remark,20414326 kshakir :
said by rcnman See Profile :

I've forwarded over to the guy who runs email.

You can get port 25 open if you buy a static ip. FWIW.
Thank you!

While I'll happily trick out my account with all kinds of packages (love the 20mbps!)-- my "dynamic" ip hasn't changed in a year, and I'd prefer not to pay RCN ransom money purely for ports 25 and 80. ;)]]> http://www.dslreports.com/forum/remark,20414326 Thu, 01 May 2008 00:24:40 EDT Re: [E-Mail] SMTP.rcn.com silently not relaying, again http://www.dslreports.com/forum/remark,20414157 rcnman : I've forwarded over to the guy who runs email.

You can get port 25 open if you buy a static ip. FWIW.
--
Jason Nealis,
Sr. Director, Video Product and Network Operations]]> http://www.dslreports.com/forum/remark,20414157 Wed, 30 Apr 2008 23:44:30 EDT [E-Mail] SMTP.rcn.com silently not relaying, again http://www.dslreports.com/forum/remark,20410623 kshakir : If you are using a configuration like the one below, you might want to check if people have actually been receiving your emails. Just ran some tests, and I'm pretty sure smtp.rcn.com is silently eating email again. No return-receipts, error messages, etc. I wonder where these messages are going...

Background:
- RCN blocks all outgoing SMTP (port 25) traffic, *except* to smtp.rcn.com. This means you cannot use smtp.yourcompany.com (port 25) to send email from home.
- You can hack around the port 25 restriction by using a third party server on another port, but this is NOT explained in the RCN help.
- Until a few days ago, you could send email from yourname@yourcomany.com using the RCN smtp server, even without login (great for visiting relatives), as long as you wer connecting from an RCN ip address.

What changed, smtp.rcn.com seems to:

- Still relay email if it comes From:
> any_user@rcn.com
> any_user@gmail.com (evidence of a whitelist??)
> (possible other whitelist domains I don't know)

- Silently NOT relaying message From:
> any_user@yourcompany.com
> any_user@yahoo.com
> any_user@( most domains ).com

Net result: If you work at home, you cannot use smtp.rcn.com, nor your own server, to send email for work, and are forced to sign up for a third party alternate-port server like gmail (here's to hoping you don't have certain customer email, which you might not want relayed through google ;)).

Anyone know how to report this? I spent hours the last time and got nowhere with the CSRs or sales departments. Posted here and it was fixed pretty quickly, so hoping someone is listening again!

(It'd be nice if RCN unblocked outgoing 25, but I understand that we're currently fighting a war on spam.)]]> http://www.dslreports.com/forum/remark,20410623 Wed, 30 Apr 2008 12:33:09 EDT