SMTP Server Roundup

NTMail
NTMail supports Enhanced Simple Mail Transfer Protocol (ESMTP), POP3, and IMAP4. HTTP supports Web access to mail and system administration functions. The product also supports the Finger and Passwd protocols, which let users publish information about themselves and let Eudora users change mail passwords from their mail client. NTMail supports three account types. For the first account type, you can use a password that the mail-server's Registry stores to create an NTMail account. For the second account type, you can define an NT group with the same name as the email domain to create an NT SAM database account for NTMail. For the third account type, you can store account information in a custom database. To employ the third account type, you must write a custom DLL to provide an interface between NTMail and your database. NTMail supports APOP and AUTH to provide secure client connections.

Installation. NTMail was one of the easiest to install of this group of products. The installation file is a single self-extracting executable file. When you run this program, the installation wizard starts. The wizard asks you to verify basic information such as mail domain name, server IP address, company name, and installation directory and enter a password for the Postmaster account. You must supply more information if you use a dial-up Internet connection rather than a permanent network connection. After installation completes, you can view the NTMail Release Notes.

I used a Web browser to connect to NTMail on port 8000 and enter the license keys. The product documentation didn't include instructions for entering license keys; luckily, I found these instructions in the email message that contained the license keys.

Documentation. The Lab's review copy of NTMail shipped with two manuals, the Administrator's Guide and the Reference Guide. Both manuals ship in hard-copy and PDF format. The software's retail version will include a user's guide. The Administrator's Guide includes a good introduction to Internet mail concepts, including DNS and the relationships between various mail protocols.

Configuration and management. NTMail doesn't have a standalone administration and configuration utility; you use your Web browser to administer the product. You can use the Web-based administration tools to tune the software for performance. You can set the number of concurrent connections to NTMail for incoming SMTP mail, outgoing SMTP mail, POP client connections, IMAP client connections, and Web mail connections to a maximum of 255. Although this number of connections is certainly adequate for many organizations, the limitation affected my benchmark tests, which required a concurrent connection for each simulated user. However, one simulated user in my benchmark tests generated a much larger mail load than any individual user would generate. Although Gordano says 255 threads is more than sufficient for some very large sites that use NTMail, I suspect that large organizations with POP or IMAP clients that connect every few minutes to check for new mail might find 255 threads limiting.

Gordano supplies the mail.exe utility with NTMail for diagnostic and scripted operations. Some of the utility's functions are meant to be used interactively (e.g., to look up MX records associated with a particular host name). Other functions are intended for scripted or batch operations (e.g., to create a batch of new users from a text file).

NTMail has flexible support using NT accounts for mailbox access authentication. The easiest method is to create a group on the mail server with the same name as the mail domain. The software automatically creates mailboxes for group members. Alternatively, to support multidomain environments, you can create the group on a member server anywhere on the network or on the PDCs of several domains.

POP, IMAP, and Web access. Using POP3 and IMAP4 clients to send, receive, and manage email was easy and unremarkable. I found no surprises in this phase of the testing. I sent and received mail, created IMAP folders, and moved mail between folders.

Web access is the most convenient way to access NTMail. Because Web access requires no special client program or profile, you can retrieve your email from any computer that can provide a network link to the NTMail server. In addition to letting you read and send email, the Web client also lets you edit information that the software returns in response to a Finger request and establish automatic replies to incoming email messages. The software lets you limit the frequency at which the software sends your automatic reply to people who regularly email you once every n days.

However, for reading and sending email—what the majority of users most want to do—NTMail Web access support is a failure. When you want to view a list of your incoming messages, you can see only five messages at a time, and NTMail lists incoming messages in chronological order, forcing you to wade through your older messages before you can read the newer ones. When you finally get to view new messages, all of the SMTP headers display, which makes finding the text portion of the message difficult, particularly if the message is short. You can't resize the portion of the screen that the program dedicates to message display, and the screen is so small that you need to scroll through all the headers to find the message, as Screen 6 shows. The Web interface allows no access to folders—all email messages display in one list. I would use NTMail's Web access mail client only if I were desperate.

List-server features. NTMail includes an integrated list server that is limited to a maximum of 250 members per governed list and a maximum send rate of 5000 messages per hour. For larger lists or faster throughput, you must purchase NTMail's companion product, NTList. NTList is a full-featured product that integrates tightly with NTMail. You can run NTList as a standalone list management server with other mail servers, such as Microsoft Exchange. You administer NTList through the same Web interface that NTMail uses, and NTList supports both moderated and user-selectable digested lists. You can control list access in many ways; for example, you can restrict lists to list members, password-protect lists, and employ wildcard email address restriction. You can also configure list access to be unrestricted or shut down list activity without deleting the list.

Performance. Although NTMail's performance is respectable, its tested throughput, at 34.3tps, is half the throughput rate of the fastest server in this group. Even so, 34.3tps is more throughput capacity than most organizations need.

Final valuation. As a standalone package, NTMail is my least favorite product of the six I tested. If you need licenses beyond 50 users, NTMail is more expensive than better-performing and more fully featured systems. Although the product has a Web client, the client is painful to use. Finally, NTMail's performance-tuning options are more restrictive than those of some of the other servers in this group. I can't recommend NTMail.