Technologies for working anywhere

This is the second in a series of Flexibility articles aimed at IT, telecommunications and facilities managers and others responsible for specifying, designing, putting in place and supporting the electronic infrastructure for anywhere / anytime working.

Here we examine the various technologies that allow users away from the main office to connect to their corporate voice and data systems.

For most people undertaking office work away from their main office, either full-time or part-time, the ideal solution is to "stretch" the corporate desktop in its entirety to the remote location. In theory this means:

• The telephone operates without compromise as a fully-functioning extension on the corporate telephone network.

• The computer operates without compromise as if it were connected directly to the corporate wide area data network.

In current practice compromise is almost always necessary, as the costs of providing fully functional, high bandwidth voice and data connectivity are still prohibitive.

Here we examine the strengths and weaknesses of four solutions for remote access:

• Full voice and data routing

• Voice divert, data dial-up

• Voice divert, data via ISP

• IP only

Solution 1: Full voice and data routing:

This solution currently comes closest to the conceptual ideal, though with data bandwidth restrictions and cost implications:

• ISDN is installed at the remote location, together with special routing equipment

• All corporate telephone network services and features are extended to the remote location over one ISDN channel

• The corporate local area network is fully routed to the remote location, using data compression to increase the effective available bandwidth.

The strengths of this solution are seamless operation - the phone and PC at the remote location (e.g. home) operate identically to the office.  Also online user and technology support services can remain unchanged.

The weaknesses are modest data speed (even with compression), long-distance phone calls and relatively high capital expense.

 Solution 2: Voice divert, data dial-up:

This is probably the most popular solution currently, largely because it is cheap to implement:

• Inbound voice calls are diverted to the remote location by the corporate PBX or public network; outbound calls are dialled directly or via the PBX

• Modem or ISDN dial-up (with or without compression) provides data access to a remote access server or, for web browsing, to an internet service provider.

The strengths of this approach are that its costs are low and that it is easy to configure.  The weaknesses are low data speed, non-seamless operation, long distance phone calls and the need for special support arrangements.

Solution 3: Voice divert, data via ISP:

In this option, an Internet Service Provider (ISP) is used to provide data acc

• Voice is handled as in the previous section.

• Data connection is achieved using internet "tunnelling": this effectively allows the internet, rather than the telephone network, to provide the secure link into the corporate systems.  The new high bandwidth internet access services such as ADSL, cable modems and fixed radio can be exploited to good effect.

Strengths are low equipment and usage costs (unmetered internet access services can be used) and relatively easy configuration.  Weaknesses are possible security concerns, internet bottlenecks, low data speed using modem or ISDN internet access and difficulties in managing remotely.

Solution 4: IP only:

Making greater use of the Internet will probably be the preferred solution of the future:

• Telephony is delivered via the PC using "voice-over-IP"

• Data connection is as in the previous section.

The strengths are full location-independence, no long distance calls and low equipment costs.  As the internet improves, high speed unmetered access becomes available and wireless services are launched this approach can only get better!  Weaknesses are that it is still relatively unproven, voice quality and grade of telephony service may be variable and Internet bottlenecks may further degrade service.

Nevertheless this is a "fully converged" solution and will also support the widespread use of online meeting and collaboration tools.

The inventor of the Internet, Vinton Cerf, proudly wears a T-shirt proclaiming "IP under everything"!  In due course all corporate communications will probably be built on the Internet Protocol.

Next article: The location-independent desktop