If you’re a casual observer of the DSL market – heck, even if you’re a bit of an insider – you might not realize that very high-speed DSL (VDSL) is growing like wildfire (something we know about firsthand, having been sent running by the recent events in Southern California). VDSL is not everywhere – a nice way of saying it’s not happening in the U.S. yet – but in certain markets, VDSL is reaching or about to reach millions of customers, offering fiber-like speeds over the existing copper infrastructure.

Now, we know you’re thinking: Haven’t we been hearing about VDSL being the “next big thing” for years? What’s different now? The short answer is standards. After the VDSL Olympics earlier this year, the T1.E1.4 Working Group and the IEEE 802.3ah Ethernet in the First Mile (EFM) Task Force chose DMT over the competing QAM line code as their standard for VDSL deployments. While the ITU-T hasn’t yet reached a decision, the EFM and T1.E1 decisions seem to provide enough consensus for telcos around the world to move forward with their VDSL deployments.

The biggest adoption of VDSL has taken place in Asia, with Korea and Japan leading the way. In both of these countries, where DSL deployments have been incredibly successful, we’ve seen an ongoing “speed war” between competitors. Even basic asynchronous DSL (ADSL) services offer speeds - often 10M bit/sec or higher - that make North American 1.5M bit/sec DSL look paltry by comparison.

In Korea, VDSL deployments are already underway, with 10M and 20M bit/sec service deployments in place. Since the EFM and T1.E1 decisions, vendors we’ve spoken with tell us they are seeing large orders for DMT-based equipment, which, they say, is replacing QAM equipment in major urban deployments such as Busan and Seoul. KT is offering customers 50M bit/sec downstream/11M bit/sec upstream VDSL for not much more than their existing ADSL services, and Hanaro (KT’s biggest competitor) is also moving into VDSL deployments.

In Japan, similar deployments are being pursued by NTT and KDDI. NTT offers 50M bit/sec downstream/ 30M bit/sec upstream services, and KDDI outdoes that by offering a 70M/30M bit/sec service. NTT charges a premium of only $2 per month over its ADSL pricing for this high-bandwidth service.