Consumer moves away from old-fashioned landlines are the major challenge. But major telecommunications companies such as AT&T, Verizon and Sprint Nextel (NYSE:S) are also struggling to make more money from customers who now spend more time sending text messages or using the Internet on wireless phones than talking, The New York Times reported Wednesday.

"In short order, sentiment in the telecom sector has gone from bullish to guarded to ... well, slightly queasy," Craig Moffett, a research analyst at Sanford C. Bernstein & Company wrote in a recent report, referring to increased competitiveness in the market.

Maintenance costs for upgrading landlines might even lead some traditional telecommunications firms to consider giving up the business altogether, encouraging their customers to jump to wireless options, suggested one anonymous executive.