Wireless Email - 18 Apr 2001

Work around the pitfalls of wireless functionality

About 5 years ago, I tested my first wireless email device—an early wireless modem that I plugged into a Windows CE 1.0-based handheld PC (H/PC). The combination was large and clumsy but much smaller and lighter than any notebook PC. I took the device on a business trip, and when I arrived at my hotel, I tossed my suitcase on the bed and automatically began searching the room for a power outlet near the phone. I planned to go through my usual routine of checking my email while waiting for room service. I was about to dial room service when I realized that I didn't need a phone to check my mail. I had a battery-powered Personal Digital Assistant (PDA) and a wireless modem. After ensuring that wireless connectivity worked in Seattle, I left the hotel and read my email at a local sushi bar.

After that experience, I didn't want to return the test device to the vendor. When I inquired about the cost of keeping it, I was shocked. The vendor wanted $500 for the modem, and the attendant service would run as high as $400 per month. Needless to say, I resigned myself to wired email, but I've always cherished that experience—and I've taken every opportunity to test new wireless alternatives.

Through the years, I've learned a great deal about how to use wireless email. The technology is one of the most exciting to come along in years, but it's also one of the most problematic for systems administrators. If you're interested in wireless technologies, you need to understand the basic types of devices. In their current state, these devices offer many benefits but also introduce many problems. Keep reading: I have a solution that might work well in your environment.

Two Kinds of Wireless Devices
I've used many kinds of wireless devices for email access, including wireless modems that work with both PDAs and notebook PCs, and various pagers. I've also used digital cell phones—either with a PDA or by themselves—for email. In my experience, these devices fall into two broad categories: devices that require you to use a special email account specific to the device and devices that give you access to your regular email account.

That wireless modem that I tested in Seattle had its own email address, as do most pagers and dedicated wireless devices, such as the Palm VIIx that I carry today. These devices don't give you direct access to the Internet or corporate data, but they provide access to email and other services specific to the device. For the purpose of this column, I call all wireless devices that have their own email address first-generation devices. (At first glance, first-generation devices seem needlessly complex—because of the need for a separate email address—but as you'll see in a moment, you can work around that complexity.)

Second-generation devices—those that provide wireless access to your regular email account—include notebook PCs or PDAs that use a Cellular Digital Packet Data (CDPD) modem, or PDAs that work in conjunction with a cell phone that's based on the Global Standard Messaging (GSM) or personal communications services (PCS) standard. Unlike first-generation devices, these devices give you direct wireless access to the Internet and corporate data. Palm users can get a Mobile Internet Kit (MIK), which lets you connect the PDA to a digital cell phone and use the cell phone as a wireless modem. An MIK will work with a slew of GSM and PCS phones. (For a list of such phones, go to http://www.palm.com/software/mik/phone.html.) Most Windows CE and Pocket PC users can obtain the same functionality by using a Socket Communications Digital Phone Card (DPC). Socket Communications' DPC cards also work with notebook PCs.

Second-generation devices should—by nature—be superior to first-generation devices, but for three reasons, this expectation isn't always met. First, no second-generation device provides coverage that is truly nationwide. (Some first-generation devices—notably pagers—do.) These devices are all based on some flavor of digital cellular service. As travelers are all too aware, not all services are available in all areas. CDPD is particularly annoying because the modem requires a separate account with a wireless carrier (just like a cell phone). Service is flawless in major metropolitan areas, but you're likely to encounter gaps in coverage when you travel the countryside.

Second, none of the broadly available wireless technologies provide a data rate higher than 19.2Kbps, which simply isn't fast enough to let you efficiently access a regular email account. To compensate for this deficiency, the email applications built into wireless-capable PDAs let you view only message headers. You then decide whether to download a complete message. However, you end up wasting time looking through headers of messages that you won't download. And don't even think about downloading binary attachments. Although some devices (e.g., Windows CE 3.x- and Windows CE 2.x- based H/PCs, Pocket PCs) let you download attachments at 19.2Kbps or slower, the download takes an eternity. (As a workaround, some people carry a wired modem. When they need to download a long message or attachment, they find a phone line and power outlet and connect the old-fashioned way.)

Third, although second-generation devices claim to provide direct access to corporate email accounts, such access doesn't usually work. For example, CDPD modems give you wireless Internet access, but only through the wireless service provider's gateway. The service provider assigns your device an IP address in the provider's domain (not your company's domain) and provides DNS services. Therefore, you can access corporate email only if your company uses a public POP3 or IMAP4 server. (If your company is security-conscious, such a setup won't be an option.) You can use a somewhat more flexible GSM or PCS phone for wireless access to any standard dial-up server (provided the system uses simple username and password access control), but you can forget about access to systems that use complex authentication schemes. Also, I have yet to find a wireless device that works through a VPN portal—although Certicom offers VPN software for PDAs. (For more information about Certicom's solutions, go to http://www.certicom.com/vpn.html.)

Using a second-generation device for corporate email access also involves considerable cost. Wireless providers frequently charge on a per-message or per-kilobyte basis, comparable to the per-minute charge for cell phone use. On any second-generation device, you'll also get hit for roaming charges when you're outside the local area. (First-generation devices tend to be cheaper. You can buy "all you can eat" wireless access for as little as $39.95 per month.) The dream of pitching your modem cable and enjoying seamless access to corporate email without wires is exactly that—a dream.

A Better Way
If you simply must use a wireless device—either first-generation or second-generation—for corporate email access, I have a solution for you. Instead of trying to read all your email on the wireless device, try using the device only for high-priority messages and limit the device to short, plaintext memos.

Imposing such a limitation is easy because most of today's corporate email systems support rules. I recommend that you use these rules to selectively forward to your wireless email device only messages that fit the aforementioned parameters. I've used this technique for years—first using a corporate Microsoft Exchange Server system and more recently using Microsoft Outlook 2000 as a desktop client to my ISP's POP3 server. Here's a set of rules that I've used with some success:

  • The system forwards short (e.g., smaller than 1000 bytes), high-priority messages to my wireless email account, as Figure 1 shows.
  • When the system receives a long (e.g., larger than 1000 bytes), high-priority message or a low-priority message, it sends an automatic out-of-office reply to the sender.

I recommend using a standard out-of-office message, the text of which can explain that you have a wireless mailbox and that the system will automatically forward short, high-priority, text-only messages. That way, people who need to reach you quickly will know how to do so.

This approach has the virtue of hiding your first-generation device's wireless email account. People don't send mail to that account; they simply send the mail to the regular account and the system forwards the messages. Also, the underlying technology (e.g., alphanumeric pager, Palm VII, Pocket PC with a CDPD modem) doesn't matter. All that matters in message-forwarding is that you have a separate email account for wireless use.

What if you have a second-generation device that doesn't have a separate email address? The answer is simple: Provide one. Any standard POP3 mail server can provide an email account. If your company runs a public server that's outside the firewall, you can use that server. Alternatively, you can set up an account with MSN Hotmail or another free email provider. This solution also lets you read messages from any Web browser if you wander outside the wireless coverage area or if the device's batteries die.

If you're a one-person shop, or if you already buy your email service from an ISP, you can apply the aforementioned rules to your desktop PC (i.e., set up Outlook to dial in hourly and apply the three rules). However, a solution that I'm more comfortable with is Primate Systems' server-based agent MonkeyMail (http://www.monkeymail.com), which scavenges my regular email account, grabs messages, and forwards them to my Palm VIIx. The only problem I've encountered is the lack of a simple way to turn MonkeyMail on and off. (Outlook's rules give you nice flexibility in this area.) Therefore, my Palm VIIx's mailbox periodically fills up, and I must manually clean it out. Fortunately, Palm's cleanup process is fairly easy—simply go to http://myaccount.palm.net, and select Mailbox Cleanup from the menu. MonkeyMail works with any mobile device, including pagers and mobile phones, that has an Internet address.

Only the Beginning
Of course, this short column doesn't provide a complete overview of wireless email. I haven't touched on the middleware solutions that provide direct access to corporate email—as I hope to do in future columns. Additionally, some readers—particularly those who work in secure environments—might object to my suggestion to forward messages to an unsecure POP3-based system outside the corporate LAN. (Indeed, the topic of wireless security warrants a separate column.) Suffice it to say, any system that transmits data by radio runs the risk of interception.

I hope this column has opened your eyes to the possibilities of wireless email. Although message-forwarding might seem crude, it's a great way to experiment without incurring a tremendous investment in specialized hardware and software.

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