hour, or five per second, with almost no errors. >> reporter: so the site can handle high volume, but security may be another scory, because there are two main components to the federal exchange and one part was never security tested all together before going live. that was so security improvements could be made after october 1. >> was there ever any end-to-end testing on the exchange? >> there was end-to-end testing on the hub. there was individual modular testing and demonstration testing inside the exchange, meaning we had sample cases, sample situations that we tested all the way through. we obviously could not test live until we went live. >> reporter: the top republican and top democrat at today's hearing said they are optimistic the website will be mixed, but there were lawmakers on both sides of the aisle who gave the website a failing grade. >> after nearly $400 million,