Bitcoin exchange faces DDoS, even as the digital currency surges

Bitcoin exchange Mt. Gox faced a distributed denial-of-service attack late Thursday, at a time the digital currency is seeing an upward swing.

The Japanese company, which is rated as the largest exchange for bitcoins, was hit by a DDoS attack that was "stronger than the average," the exchange's support team said. Such attacks aim to overwhelm systems by sending an overload of requests to websites.

Bitcoins use a distributed, peer-to-peer cryptographic system to verify transactions. A number of websites including blogging platform WordPress and social news site Reddit have started accepting payments by bitcoins. Expense reports management software firm Expensify said this week that it added bitcoin as a reimbursement option for expense reports. "We see Bitcoin as more than just a gimmick," it said in a blog post.