Virgin Media UK has begun a market test of the world's fastest cable connection -- a service boasting up to 1.5 Gbps downstream and 150 Mbps upstream. The connection is delivered over the same HFC infrastructure and technology as Virgin Media uses to provide residential customers with speeds of up to 100 Mbps, which is currently being rolled out to over half of all UK homes. The 1.5 Gbps service is being tested in east London around Old Street, an area known as "Silicon Roundabout." The high performance is enabled by DOCSIS 3.0 channel bonding.