Not even the biggest economic downturn since the Great Depression could slow the ongoing explosion of traffic over international Internet connections, and service providers are still building to accommodate it.

The world economy slid into crisis about a year ago, crippled by key events such as the bankruptcy filing by investment bank Lehman Brothers, which occurred one year ago Tuesday. But between mid-2008 and mid-2009, the volume of Internet traffic between countries has actually grown faster than the prior year, according to research company Telegeography.

International Internet traffic has grown at 79 percent since last year, up from 61 percent in 2008, a study released Monday found, according to a Telegeography press release. The study focused on links between, rather than within, countries.

International traffic has more than doubled in the past year in emerging markets, including Eastern Europe, South Asia and the Middle East, but more mature regions are also seeing rapid growth, the company said. Traffic on international links connected to the U.S. and Canada grew 59 percent.

Despite hard times, carriers have not been shy about building up their networks to handle the new traffic, which is being driven by new video services as well as mobile data hitting the wired backbone and other factors. For example, India's Tata Communications said last month it would increase the capacity of its 6,700-kilometer TGN-Intra-Asia undersea cable, which went into operation just this year. TGN-Intra-Asia was designed partly to alleviate bottlenecks between Japan and Singapore and currently has a capacity of 650Gb per second (Gbps). It originally was set for expansion next year, but demand has grown, partly because the cable bypasses a seismically active area around Taiwan where some other cables have suffered earthquake damage.

Service providers have been building up their international network capacity by 60 percent or more since 2007 and added 9.4Tbps of new international capacity just this year. Only two years ago, all international Internet links combined added up to just 8.7Tbps, according to Telegeography. Despite that expansion, the average utilization of networks has grown in some areas, rising from 56 percent to 62 percent within Asia.