Mobile Middleware in the Broadband Era

With mobile broadband networks like EV-DO and HSDPA becoming more widely available, many IT managers are asking about the role of mobile (or wireless) middleware. Is it still needed with the higher speeds? The answer is yes, but the reasons have changed. For background, mobile middleware is the system that operates between amobile device and a server. Usually it consists of software on a mobiledevice and a mobile server that acts as a proxy for the mobile node soit can communication with an end server such as a mail server, Web serveror database server. The objective of this architecture is to optimizethe communication between the mobile node and the mobile server for wirelessconnections, addressing such unique wireless communications challenges asslower speeds, higher and variable network latency, intermittent connections,changes in IP address because of connections being reestablished and so forth.

In its earliest forms, mobile middleware made it feasible to use really slownetworks such as Mobitex and CDPD with applications that would have performedmuch too slowly in their native form. Today, with typical speeds of 3G networksapproaching a megabit per second, speed is less of an issue. In fact, manynetworking applications will function quite well with no middleware assistance,especially with light use. However, the mobile environment is still fundamentallydifferent from the high-speed Ethernet world over which many networkingapplications function.

I can see this with my use of a Treo 650 and POP e-mail, where about 20 percentof e-mail downloads fail because of variable delays and occasional slow throughputthat confuse either the TCP or the POP3 protocols and result in timeouts. Comparethis with a RIM BlackBerry architecture that is rock solid in its mail delivery,regardless of wireless network type. Why? Because it employs a mobile middlewarearchitecture, including the BlackBerry Enterprise Server and RIM's NOC.

The same goes for the other wireless messaging gateways. With sufficient mobiledesign emphasis, there's no reason that direct client/server interaction cannotbe improved for the mobile environment -- as Microsoft has done with Windows Mobile5 and SP2 for Microsoft Exchange. However, this is not the case for most applications.So we are left with a situation where even Web browsing over EV-DO and HSDPA can beenhanced by a factor of two to four using Web optimization (another form of mobilemiddleware). With today's busy Web pages, downloading a Web page in 3 seconds insteadof 10 over a 3G connection is a noticeable gain.

However, speed is just the tip of the iceberg. Another crucial element is security.Most enterprises employ VPNs for remote access, including 3G wireless use. Oneapproach is to use a standard VPN from the likes of Checkpoint, Nortel or Cisco,which is certainly feasible. But an increasingly popular alternative is to usemobile middleware with VPN functionality (referred to by some as mobile or wirelessVPNs) from companies such as Ecutel, IBM, ipUnplugged, NetMotion Wireless and Padcom.Not only do you get the secure tunnels, but you also get transport optimizationthrough compression. In addition, depending on vendor, you may get importantfeatures such as session maintenance, so if you lose connections -- dropping fromcoverage, for example -- the mobile middleware maintains your application sessions,allowing them to quickly resume once you are back in coverage. Some mobile middlewaresolutions also allow users to maintain secure applications sessions even as theirnetwork changes, say from 3G to Wi-Fi.Another increasingly important and relatively new function that mobile middlewarecan potentially support is policy enforcement. This is where the mobile middlewareenforces what applications can access the network with what network connection type.If you only have limited bandwidth because you've roamed into a 2.5 G coverage area,it might be nice if bandwidth-hogging applications such as Windows auto-update wereput on hold, letting you download your e-mail efficiently. With so much automaticnetworking activity occurring on today's laptops, this is a feature I can trulyappreciate -- currently, I manually disable virus updates, Windows updates, spywareupdates and so forth before using my wireless connection.

And what if your enterprise policy is to always use a VPN for networking, but youfind yourself at a wireless hotspot where you need to use a browser outside of thetunnel to enter your hotspot login credentials? Some mobile VPNs can let you do thisby temporarily allowing a browser session outside the tunnel.

The benefits of mobile middleware are quite clear, but which specific solution touse can be much less obvious. Feature sets and architectural approaches vary considerablyamongst the vendors. The challenge is sorting through all the available approaches;not only are there mobile middleware vendors dedicated to this space, but the mainstreamapplication vendors and VPN vendors are also adding mobility functions to their products.

Bottom line: If you or your users are making light use of wide-area wireless networks,you can probably get by without using mobile middleware. But if you're going to doany heavy lifting, where applications will be doing large numbers of networkingtransactions every day, where you may have a large number of users in the fieldand user productivity can only be achieved through applications that work extremelyefficiently and reliably, then you seriously need to consider mobile middleware aspart of your overall architecture.