The three-hour outage came after aon Thursday for six hours. Both involved issues with the cable giant's domain name servers, which translate and route Web page requests from users. Although Internet applications such as instant messaging could continue to operate, Web site requests either did not respond or were sluggish.
A Comcast spokeswoman said Tuesday night's outage was first noticed about 6:30 p.m. PT and service was restored about three hours later.
"We were able to identify the situation right away," Comcast spokeswoman Jeanne Russo said. "We are working with the (hardware) vendor to make sure it doesn't happen again."
Russo declined to identify Comcast's hardware vendor.
Throughout online message boards, including Comcast's own forum, subscribers fumed at the company's second outage in four days. Michael Spoonauer, a software engineer and Comcast customer from Quincy, Mass., noticed the issue Tuesday evening when Web site requests continued to time out. Spoonauer said Comcast's support representative told him that that the network was experiencing an unscheduled outage due to server maintenance.
Spoonauer bristled at Comcast for not informing its users about the outage, and added that the company's Web site offered little information about why the service was down again.
"I would consider it to be corporately responsible to send a message to customers saying what happened, why it happened and what they're going to be doing to prevent it," Spoonauer said. "It's not too much to ask from a company."
Comcast's Russo said the company communicates issues through areas on its Web site and sometimes through recorded messages that greet callers.
Comcast is the nation's largest broadband Internet access provider. It reported 7 million subscribers at the end of 2004.