The company says Liddell's appointment follows a number of important milestones for the two-year old CDN, including the recent announcement of Dennis Morgan as CFO earlier this month and its 300th customer win in April.

"Steve's extensive background in telecommunications will be very valuable for Panther Express," says Kevin Ryan, chairman and cofounder of Panther Express. "He has a well-established reputation as a strategic thinker and has successfully scaled a number of early stage businesses. His considerable experience building sizeable international businesses will help Panther advance to the next level of its development and galvanize its position as a formidable contender in content delivery."

Panther Express says Liddell is "highly skilled in all aspects of growing and operating international telecommunications businesses" and was most recently an independent consultant advising private equity firms Columbia Capital and MC Venture Partners on their recent acquisition of GTS, an Eastern European telecommunications operator.

Prior to that, Liddell was chief operating officer of Clearwire International, and from 1999 to 2005, Liddell worked at Level 3 Communications as president of Asia and later as group vice president.

In February, the company reported it had closed a $15.75 million Series B round of venture financing led by venture capital firm Index Ventures to support its international expansion to support its growing list of customers.