Pairgain technologies, which convert analog traffic to digital, can carry 32 conversations. This increases capacity without the expense of increasing the number of wires. These technologies serve different tiers of service at different price points, and all will be part of the evolving telecom landscape. These vendors make or acquire the access, switching, and transmission technologies necessary to build a network from end to end. Big, diversified, and well followed, these companies tend to be fairly valued, so I'm not buying any of them right now.
Good values do arise from time to time.
Small companies are driving the market in access devices, which concentrate traffic from different sources onto digital trunks connected to the central office. Many access devices connect one of the broadband data-transmission standards like asynchronous transfer mode or frame relay to the switched telephone network. More sophisticated devices offer integrated access for multiple forms of data and voice traffic transmitted over digital trunks to the central office. Premisys competes with Newbridge Networks, Tellabs, and Nokia, but offers the most flexible and powerful integrated access solution. The portfolio is underweighted in communications stocks, which had been overvalued for months before coming down hard in the first quarter.