There is some movement in the marketplace, and small business subscribers may finally benefit.
Copper access may be getting better. The introduction of new kinds of high-speed modem, together with efforts to reduce network congestion, will help carriers introduce new services. A family of high-bit-rate digital subscriber line solutions known as xDSL now permits both symmetrical and asymmetrical digital access to be provided to small businesses and telecommuters.
Service management is also improving in the access network and at the customer premise.
When teamed with SONET (synchronous optical networks) and asynchronous transfer mode (ATM), xDSL can bring switched digital video (SDV) much closer to the subscriber.
Emerging technologies such as DSLAM (digital subscriber loop access multiplexer) and SDV make better use of the existing copper infrastructure, although their penetration is currently limited mainly to field trials.
NETWORK CONTROL
High-bit-rate transmission alone cannot enable carriers to deploy, and subscribers to choose specific services. Broadband must be supported with intelligent networking that includes:
* Control over different kinds of services.
* End-to-end network management.
* Intelligent customer premises equipment (CPE).
The vendor community is trying to solve these issues with a series of products that lower the cost of handling data traffic and create the potential for new revenues for carriers and Internet providers.
When subscribers download large blocks of data or video-enhanced clips, they need both bandwidth and continuous bit rate. When high speed is not required--for example, when reading e-mail--subscribers should be able to switch to a lower bandwidth and a variable bit rate.
Buying the throughput they need from the LEC gives subscribers some control over cost. For example, Northern Telecom's Service Controller for High Speed Data product delivers point-and-click access to multiple networks and the ability to choose speeds on the fly.
The Controller works with any access medium--from copper to coax. It supports hybrid fiber coax (HFC) and xDSL. It also doubles as a broadband Service Control Point (SCP) by providing network intelligence for high-speed access.
EASING CONGESTION
Data caller patterns differ from those of telephone users, leading to potential capacity problems for telcos. Congestion can occur anywhere--at the subscriber premises, in local loop, or in the backbone network--so no single solution works.
One approach is to use a multivendor access module to take data out of the voice network before it even reaches the originating switch.
Another strategy, requiring no change to a carrier's access network, is to provide tandem relief by capturing the data after it is routed by the local switch.
The ISP collects the data over high-performance ATM and frame relay tandem circuits without having to put its own server in the central office. Nortel's Internet Thruway system uses tandem circuits to separate Internet traffic from voice. Launched in August 1996, it was adopted by Southwestern Bell to support Internet/Intranet access.
Thruway solves only part of the problem, however. Also needed is an end-to-end network management system that allows carriers and ISPs to deliver and monitor new services over the dial-up network. To do this they need:
* End-to-end service management.
* Operations support for the Internet.
* Network status reporting.
* Grade of service flexibility.
All elements of Thruway are managed from one platform, with integrated surveillance, performance measurements, provisioning, and billing. The ISP can thus monitor operations and adjust capacity as needed.
To make data more accessible and manageable for single line subscribers, specialized text-based data can be delivered either to their PCs or to proprietary data terminals.
Such a display can accommodate services such as corporate data, headline news, stock quotes, TV programming, lottery information, weather forecast, transportation schedules, and phone directories.
This telephony-based approach has the potential to open doors to the small business marketplace because new kinds of interactive services can be obtained from the Internet.
HDSL SOLUTIONS
There has been some movement in the direction of high-bit-rate digital ,subscriber line (HDSL) over the past few months. Dataquest believes that symmetrical services will change the dynamics of the xDSL market.
