Thunderbolt, originally introduced in February on Apple's Macintosh computers, was pitched as being optical technology but currently uses copper wires. Fiber optics are expensive to implement, and copper wires are working much better than expected, said Dadi Perlmutter, executive vice president and general manager of the Intel Architecture Group, in an interview at the Intel Developer Forum being held in San Francisco.

Thunderbolt, originally known as Light Peak, was announced in 2009 and was designed to use fiber optics to transmit data among systems and devices. However Intel and Apple released Thunderbolt based on copper, with data transfer rates between host devices and external devices of up to 10Gbps (gigabits per second). The trend of using copper wires could continue, and it could be many years before fiber optics are used in Thunderbolt.

"It's going to be way out," Perlmutter said. "At the end of the day it's all about how much speed people need versus how much they would be willing to pay."

The cost of implementing fiber optics is significantly higher than copper, and copper can transfer data at adequate speeds at this stage, Perlmutter said. There is still more room for data transfers to jump on copper.

"Copper will continue to improve, which happens. There have been many technologies that had been predicted dead 20 years ago that are still making good progress. We'll see," Perlmutter said.