comcast logoA Comcast executive told Telecompetitor today that if 400 Gbps transport equipment were “commercially available and viable,” the company would be prepared to deploy it.

“Today we bundle multiple 100 gigabit [connections] together so we could use 400 G technology today,” said Kevin McElearney, senior vice president of network engineering at Comcast Cable.

To make itself better prepared to deploy 400 Gbps technology, Comcast announced today that it will deploy a packet-optical platform from Ciena equipped with third-generation WaveLogic coherent optical line interfaces, which according to a Ciena press release are the industry’s “first software-programmable coherent technology that scales to 400G.”

Coherent optical technology is often used on transport equipment supporting speeds of 100 Gbps or higher. Unlike the optical processors used on traditional fiber optic systems that simply flash on and off, coherent optical processors work by using variations in phase and amplitude, thereby enabling the systems to support higher bandwidth.

Another reason Comcast chose to use the Ciena equipment is that the equipment has advanced signal regeneration capabilities that can minimize the number of network components — including optical regenerators — that have to be installed in the network.

McElearney said Comcast will use the Ciena third-generation coherent technology on longer network spans that require regeneration. “Everywhere we have larger spans and regeneration we would like to use WaveLogic 3 to reduce the cost of scaling to 100 G,” he said.

Today’s announcement does not mark Comcast’s first foray into 100 G. According to McElearney, the company has deployed 100 G in the “vast majority” of its backbone network and in some high-traffic metro networks.

Deployment of 100 Gbps transport equipment in backbone networks is becoming quite common, with companies as small as Dakota Carrier Network making that move. Deployment of 100 Gbps equipment in metro networks is less common.

Comcast said the requirement for higher-speed transport is driven by demand for high-speed services and applications such as HD video, mobile data and cloud computing.