<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2//EN"> <HTML> <HEAD> <META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=us-ascii"> <META NAME="Generator" CONTENT="MS Exchange Server version 5.5.2653.12"> <TITLE>RE: [JDEV] File transfers</TITLE> </HEAD> <BODY> Mike writes: > Firstly, there is no inherent problem with sending moderately > large files through a software server. Sendmail does it all > day, every day, on a massive scale, without relying on > client-to-client connections. However, most mail is accessed through POP, IMAP, or Exchange, which are definitely client-to-client connections -- for the simple reason that sendmail doesn't scale very well.  For every byte send to a sendmail server, two bytes traverse the network.  Most unfortunately, those two bytes always involve just the one sendmail server and its attached network. What positives do you get for having the sendmail server involved in a large file transaction between two parties?  You get a guarantee of delivery and no need for continued storage on the sending party's side (since the file 'moves' to the sendmail server). If you're sending the file to multiple users at once, you get less traffic on your local network (the server takes the load). You also get an opportunity to mediate the file somehow (e.g., virus checking it as a service, converting it from aac into mp3, storing it for later delivery to other users..) What positives do you get for not having the sendmail server involved?  The network on the sendmail server sees 0X load rather than 2X load; the latency is lower; the sendmail server has no storage requirement; and you have arguably fewer points of failure. Pragmatically, taking the load off the server is more valuable in the normal case than replicating HTTP/FTP/SMTP/FXP yet again. The fact that 'SMTP does it' is not a great rationale for forcing all the jabber servers to pay 2X bandwidth costs for file transfers between their users. F. <CODE> ********************************************************************** E-mail sent through the Internet is not secure. Western Asset therefore recommends that you do not send any confidential or sensitive information to us via electronic mail, including social security numbers, account numbers, or personal identification numbers. Delivery, and or timely delivery of Internet mail is not guaranteed. Western Asset therefore recommends that you do not send time sensitive or action-oriented messages to us via electronic mail. ********************************************************************** </CODE> </BODY> </HTML>