From owner-freebsd-questions@FreeBSD.ORG Sun Mar 28 20:38:54 2010 Return-Path: Delivered-To: freebsd-questions@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 62BDA1065670 for ; Sun, 28 Mar 2010 20:38:54 +0000 (UTC) (envelope-from dan@dan.emsphone.com) Received: from email1.allantgroup.com (email1.emsphone.com [199.67.51.115]) by mx1.freebsd.org (Postfix) with ESMTP id 2370E8FC16 for ; Sun, 28 Mar 2010 20:38:53 +0000 (UTC) Received: from dan.emsphone.com (dan.emsphone.com [199.67.51.101]) by email1.allantgroup.com (8.14.0/8.14.0) with ESMTP id o2SKcorZ070999 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO) for ; Sun, 28 Mar 2010 15:38:50 -0500 (CDT) (envelope-from dan@dan.emsphone.com) Received: from dan.emsphone.com (smmsp@localhost [127.0.0.1]) by dan.emsphone.com (8.14.4/8.14.3) with ESMTP id o2SKco75003753 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO) for ; Sun, 28 Mar 2010 15:38:50 -0500 (CDT) (envelope-from dan@dan.emsphone.com) Received: (from dan@localhost) by dan.emsphone.com (8.14.4/8.14.3/Submit) id o2SKcn3t003752; Sun, 28 Mar 2010 15:38:50 -0500 (CDT) (envelope-from dan) Date: Sun, 28 Mar 2010 15:38:49 -0500 From: Dan Nelson To: Ron Message-ID: <20100328203849.GD4806@dan.emsphone.com> References: <4BAED536.2060205@rzweb.com> <4baef8de.00G1oLWhtZbJ8Rwl%perryh@pluto.rain.com> <4BAFB9AC.7040406@rzweb.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4BAFB9AC.7040406@rzweb.com> X-OS: FreeBSD 8.0-STABLE User-Agent: Mutt/1.5.20 (2009-06-14) X-Virus-Scanned: clamav-milter 0.95.3 at email1.allantgroup.com X-Virus-Status: Clean X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-2.0.2 (email1.allantgroup.com [199.67.51.78]); Sun, 28 Mar 2010 15:38:50 -0500 (CDT) X-Scanned-By: MIMEDefang 2.45 Cc: Tim Judd , perryh@pluto.rain.com, freebsd-questions@freebsd.org, Jeffrey Goldberg Subject: Re: Freebsd, postfix and push email X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 28 Mar 2010 20:38:54 -0000 In the last episode (Mar 28), Ron said: > Jeffrey Goldberg wrote: > > On Mar 28, 2010, at 1:36 AM, perryh@pluto.rain.com wrote: > >> Er, no. POP3 and IMAP are "pull" services, wherein the client polls > >> the server periodically for any newly-arrived messages. > > > > IMAP, but not POP3, can be used to push, but the iPhone mail client > > doesn't support that as far as I know. It does support being pushed to > > over Mobile Me, but not on regular IMAP. > > So how is Mobil Me and Exchange Servers (MS, Zimbra, etc) doing it? > That's what I'd like to replicate on my FreeBsd server. This seems to be > a well guarded secret I'd like to crack. > > On the iPhone, at least, the phone is not polling the servers, some kind > of message (SMS?) is being sent to the phone that makes it put a little > red badge on the corner of the mail app icon telling it how many messages > are waiting. The messages don't seem to be download during the push, it's > just a count (I could be wrong about this). For ActiveSync at least, the phone has to keep a TCP connection to the server open 24/7, and the server sends a notification when a new mail arrives. MobileMe probably works the same way. The IMAP protocol supports a similar "notify on new mail" option, but for some reason Apple doesn't use it in their client. -- Dan Nelson dnelson@allantgroup.com