Portal unplugged

Workers benefit from easy, searchable access to information published on company intranets and portals. The Rolodex, binders, and thick files of correspondence that used to weigh down every cubicle are dwindling; a copier jam is no longer a work-stopping emergency. But there is one term for electronic information that speaks to its crippling limitation: “online.”

The modern workforce is scattered, operating at the mercy of slow hotel dial-up, unpredictable wireless, and flaky home DSL connections. Yet the design of most internal information systems presumes that all users have LAN-grade connectivity.

BackWeb Technologies Ltd. ProactivePortal Server’s mission is to give disconnected users transparent off-line access to portal and Web content. BackWeb manages this by maintaining local replicas of intranet content. Whereas Lotus set the standard for this approach, BackWeb extends off-line viewing to shops without a Lotus back end, something IT departments need.

There are some interesting technical innovations in BackWeb, but BackWeb’s ingenuity is outweighed by proprietary technology and unnecessary complexity. If you desperately need basic off-line capabilities now, BackWeb will get you there. But if you wait a while, its salient features will appear in the portal, Web, and OS software you’re already using.

We tested BackWeb’s ProactivePortal Server 2.0 on a pair of Toshiba Satellite Pro laptops running Windows 2000 Server. The vendor’s testing configuration included Plumtree Shared Information Server, the BEA Weblogic Java app server and the SQL Server 2000 database. BackWeb claims its solution will work with any portal server. Oracle is supported as an alternative to SQL Server.

Shifting the burden

The concept behind BackWeb is simple and familiar: Identify the network-hosted content that users care about and make a copy of it on their PCs. ProactivePortal Server is not so much a comprehensive off-line viewing solution as it is a rebranding of BackWeb’s existing push and caching technologies. It optimizes LAN replication and shifts the burden of managing replicated content from the users to administrators and authors.

BackWeb administrators control what is replicated to users. They set up user subscriptions (users can also select their own subscriptions) and create special push packages that are delivered to selected groups of users. Authors must add tags, expressed in BackWeb’s proprietary OTML (off-line tagging markup language), to documents in order to identify related files and to mark content that can’t be viewed off-line. In our view, an off-line solution shouldn’t require content changes. BackWeb’s administrative overhead is too high.

BackWeb keeps users’ local replicas in sync by shipping compressed packages of site changes to them while they’re connected. BackWeb uses “differencing” to send only the portions of files that have changed since the last update. It compresses the data to optimize bandwidth utilization.

BackWeb also performs what it calls Polite Communications, watching the network and sending updates during dips in activity. When traffic rises, BackWeb waits for things to quiet down before it starts sending again. And clients that disconnect during transfers don’t have to start over from the beginning. The BackWeb client resumes interrupted transfers at the point they halted.

Another BackWeb innovation is NeighborCast, a sort of peer-to-peer relaying. Instead of blasting all replication data to clients directly from the server, clients that subscribe to identical data can copy the changes from each other. This is a cool concept, but it doesn’t help off-line users. Unless you’re lucky enough to share a hotel room with someone who reads the same pages you do and who has already downloaded them, you’ll still have to wait for a server connection to replicate.

Missed window

In ProActive Portal Server, BackWeb tried to combine push, proxy/cache, LAN-usage optimization, and off-line viewing into a single solution that works with any portal or intranet. The result is a package that inadequately addresses each of these objectives.

For illustration, consider two things BackWeb can’t do. BackWeb’s client tracks users’ paths through subscribed content. Managers can use this to make sure a new HR policy document was actually read (or at least clicked on) by those it affects. BackWeb should analyze the tracking data to predict users’ habits and shape their subscriptions accordingly, but it doesn’t. BackWeb should push content to groups of users at the same time using multicasting. Again, it doesn’t. It also doesn’t address the needs of users of non-PC devices, and a proprietary BackWeb client is required.

Administrators must look to BackWeb for usage tracking. BackWeb impersonates users when it gathers data for replication, so Web or portal server logs will have trouble discerning between BackWeb and interactive users.

BackWeb’s shortcomings could be forgiven if it were a simple, elegant solution. It’s anything but. When off-line features become intrinsic to server software, there is almost no chance that BackWeb’s client, markup language, and convoluted server architecture will get picked up. Any off-line solution built around BackWeb ProactivePortal Server will require a lot of effort and expense for the temporary benefits it imparts.


ProactivePortal Server 2.0

Business Case: This portal server allows users to view company-hosted data when they can’t reach the LAN, but it relies on a complex, proprietary approach.

Technology Case: BackWeb’s differencing, compression, and peer-to-peer relaying cut down on network traffic, but do little to benefit disconnected users.


+ Combines proxy/cache, push, and off-line viewing

+ Innovative LAN traffic optimization techniques


– Needlessly complicated back-end architecture with high administrative overhead

– Content must be rewritten with proprietary markup language tags

– BackWeb client required

– No intelligent caching of content based on user’s access history

Cost: Starts at $50,000 for the server plus $100 per seat

Platform(s): Windows NT 4, Windows 2000 Server

Company: BackWeb Technologies; http://www.backweb.com

Scores (rating 1-10):

Ease of use (4)

Implementation (3)

Innovation (6)

Interoperability (4)

Scalability (7)

Security (7)

Suitability (2)

Support (3)

Training (4)

Value (2)

Score Summary:

“Reject” (4)