Deregulation in the UK telecomms market has failed to make a dent in BT's dominance.
A recent survey puts the telco in poll position in the number of users for traditional services such as basic telephony, as well as new functions including video conferencing.
According to this year's annual survey of members of the Telecommunications Managers' Association (TMA), BT provides basic services to 64 per cent of the 450 respondents. The nearest competitor is Cable and Wireless Communications used by 13 per cent of the respondents.
BT's dominance is unlikely to change unless the UK giant loses its monopoly of the 'local loop' - the final link to the user's telephone, agreed 66 per cent of those polled.
Said David Harrington, TMA director general, "BT owns the local loop and unless it invests heavily in upgrading its network or if there's a divestiture that will force it to open it up."
However BT's position could also be attributed to its success in turning the business around amid aggressive competition. Martyn Hart, TMA chairman said: "While other factors may be in place, that's in part down to the growth in the various markets and also a measure of BT's success in meeting the potential challenge of competitors."
He continued: "That means, paradoxically, that we need more and stronger competition, for example to do something about prices."
On the mobile telephony side, the dominant supplier is Vodafone, used by 48 per cent of respondents, followed by Cellnet with a close 44 per cent.
The TMA also praised operators for improvements in their service quality ratings. All the main suppliers used by the respondents: Energis, Worldcom, Colt, BT, AT&T, Cable and Wireless Communications, and Racal, all improved their grades from last year, albeit slightly.
The respondents awarded them ratings on a scale of one to 10, with Energis leading the pack with 7.54 points. Colt, the winner last year, fell to number three position this year, though its rating of 7.14, compared with last year's 7.08.
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