Video Boom Forces Verizon to Upgrade Network

Laboring under a surprising load of online-video traffic, Verizon Wireless has had to spend millions more this year to upgrade its network.

The cellphone carrier long enjoyed a reputation for having the country's most robust network, while rival AT&T suffered complaints about call quality. But now it is Verizon that has been caught off guard by the onslaught of data traffic, contributing to what its executives have acknowledged is a performance decline in key cities such as New York, Chicago and San Francisco. In some places, wireless download speeds on Verizon's high-speed 4G network have dropped more than 20% since last year, according to data from industry tracker RootMetrics.