Computer Sciences Corp. said Friday it had received a contract for up to $613 million to manage voice services for the Department of Defense’s Defense Information Systems Agency.

The DISA is a combat support agency that provides services to the president, vice president, secretary of defense and other DOD units. The contract extension has a two-year base period and three one-year options. Computer Sciences was in position to win the new contract after acquiring the company that has been providing network management support to the agency since 1999.

Computer Sciences shares rose 51 cents to $50.12 in pre-market trading Friday after the announcement, then fell back to $49.74 by midday, up 15 cents from Thursday’s close.

The company said Thursday it had been awarded a five-year, $113 million contract to provide supercomputer integration support for the National Aeronautics and Space Administration.