Comments on: Hotmail Delivery Problems Are Not Like Yahoo Mail’s http://www.emailbattles.com/2006/04/20/email_aadeefedia_di/ Spam, Security, Privacy, Spyware, Phishing & Viruses from the Front Lines. Wed, 08 Sep 2010 15:22:55 +0000 http://wordpress.org/?v=2.0.4 by: Thorne Wood http://www.emailbattles.com/2006/04/20/email_aadeefedia_di/#comment-745 Fri, 21 Apr 2006 22:39:42 +0000 http://www.emailbattles.com/2006/04/20/email_aadeefedia_di/#comment-745 Although this is not a case of greylisting, it delivers some messages with a slower speed rate. Although this is not a case of greylisting, it delivers some messages with a slower speed rate.

]]> by: Aaron http://www.emailbattles.com/2006/04/20/email_aadeefedia_di/#comment-744 Fri, 21 Apr 2006 14:37:25 +0000 http://www.emailbattles.com/2006/04/20/email_aadeefedia_di/#comment-744 DBarclay, plug hotmail.com into the Mail Server Profiler (http://www.trimmail.com/news/tools/) a few times, and you'll see that the first IP address for each MX record times out every single time. <br> <br> If they were greylisting early in the SMTP conversation, you'd expect to see a temporary SMTP deferral. They may be greylisting after they've determined the sender's and recipient's email addresses, but it doesn't look like they're doing it during the initial connection.<br> <br> It may be that these IPs are only for outgoing mail... DBarclay, plug hotmail.com into the Mail Server Profiler (http://www.trimmail.com/news/tools/) a few times, and you’ll see that the first IP address for each MX record times out every single time.

If they were greylisting early in the SMTP conversation, you’d expect to see a temporary SMTP deferral. They may be greylisting after they’ve determined the sender’s and recipient’s email addresses, but it doesn’t look like they’re doing it during the initial connection.

It may be that these IPs are only for outgoing mail…

]]> by: DBarclay http://www.emailbattles.com/2006/04/20/email_aadeefedia_di/#comment-743 Fri, 21 Apr 2006 11:55:21 +0000 http://www.emailbattles.com/2006/04/20/email_aadeefedia_di/#comment-743 Could Hotmail be engaging in a kind of "grey listing" by having the first IP address for each MX list always closed to incoming traffic?<br> <br> The hope might be that a dumb SPAM bot will not use the alternate MX records and give up, while a reasonable/legitimate mail server will try the other MX records and successfully deliver.<br> <br> This is slightly different from the other definition of "grey listing" that I have seen: returning a 4xx non-permanent SMTP error on the first connection from an IP, then accepting subsequent connections. The hope is that a "dumb" SPAM bot will just move on and not re-try. Could Hotmail be engaging in a kind of “grey listing” by having the first IP address for each MX list always closed to incoming traffic?

The hope might be that a dumb SPAM bot will not use the alternate MX records and give up, while a reasonable/legitimate mail server will try the other MX records and successfully deliver.

This is slightly different from the other definition of “grey listing” that I have seen: returning a 4xx non-permanent SMTP error on the first connection from an IP, then accepting subsequent connections. The hope is that a “dumb” SPAM bot will just move on and not re-try.

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