One Life Remaining (A Science Fiction Thriller) (Portal Book 2) - Portal, #2

Detective Inspector Louisa Bennett's arrest of Portal CEO Benoit Walsh and the resulting scandal have done little to diminish the network's popularity. Its hand-held terminals have been replaced by implants, providing a deeper and more personal integration for millions of devotees. Yet not everyone is so enamoured with Portal's technological utopia. Terrorists strike against the company, demanding the dissolution of its network.
When Louisa's foster son Ben goes missing she faces the possibility that he may have been involved. Desperate to save him, she must track down the terrorists before the inevitable government backlash. But the destruction of Portal is the least of the terrorists' aims.