VDSL2

Mass-market broadband access technology is hotting up again. Strong consumer demand over the last few years has made 2-Mbit/s Internet access pretty much the entry-level option, placed within the reach of virtually all consumers wanting Internet service. But the telecom landscape continues to change, and telcos are beginning to take the plunge into much deeper bandwidth waters as they gear up to offer real-time IPTV services -- especially in their impending HDTV form -- and generally converge everything they can think of onto a single high-bandwidth digital pipe into the home.

This is all part of the celebrated recrafting of the network that Light Reading continues to chronicle in detail. A big issue for telcos is what role -- if any -- copper will play in this new scheme of things. Running a couple of simultaneous HDTV channels plus online gaming and Web browsing/downloading and so on into a home will put the bandwidth demand north of 20 Mbit/s, and therefore out of reach for most users of even the fastest flavor of ADSL. Fiber (especially GPON) and Ethernet in the First Mile clearly have a big role to play, but will not, or cannot, be used everywhere.

Fortunately, a new DSL standard -- VDSL2 -- has recently been published by the International Telecommunication Union, Standardization Sector (ITU-T) , and it appears to be garnering wide support within the industry as defining an important technology for supporting mass-market IP/Ethernet broadband access at many tens of megabits per second -- up to 100 Mbit/s, in theory, over short ranges. A key attraction is that VDSL2 can be deployed in mixed CO/cabinet modes in parallel with existing ADSL/ADSL2/ADSL2+ systems, thereby providing a migration path.

So what can the new VDSL2 do? What improvements does it offer over the earlier, ill-fated VDSL1? How does it perform in the field? And what are the migration issues in moving from the various flavors of ADSL to VDSL2?

Here’s a hyperlinked contents list:

• Page 2: VDSL2 Technology & Standards

• Page 3: VDSL2 Bandplans

• Page 4: Deploying VDSL2

• Page 5: VDSL2 Migration Issues

Webinar

This report is based on a Webinar, VDSL2: Deployment & Migration Issues, moderated by Andy Bray and sponsored by Ericsson AB (Nasdaq: ERIC). Speakers also included John MacDonald, representing the International Telecommunication Union (ITU) . MacDonald played a key role in the development of the VDSL2 standard and is in charge of DSL performance evaluation for BT Group plc (NYSE: BT; London: BTA). An archive of the Webinar may be viewed free of charge by clicking here.

About the Authors

— Tim Hills is a freelance telecommunications writer and journalist. He's a regular author of Light Reading reports.

— Andy Bray is Principal at Netrius Associates , a marketing consultancy firm based in the U.K., and active in telecommunications and digital media.

Next Page: VDSL2 Technology & Standards