Don't think the current telecom lull means there's nothing going on. There's a massive shift underway from circuit- to packet-switched networks. And carriers looking for a way out of the downturn will eventually have to buy their way out by investing in technologies that enable them to offer revenue-rich data services.

Enter Virtual Private LAN Service (VPLS), or Transparent LAN Service. An emerging subset of technologies, VPLS has captured the collective imagination of the telecom industry as a preferred alternative for creating Virtual Private Networks (VPNs), which allow corporate users to secure pipes through public networks.

In fact, VPLS has generated so much interest that Light Reading's paid research service, Optical Oracle, has devoted an entire report to the topic -- "VPLS Variations," released to subscribers this month.

VPLS stands out from alternative technologies, such as IP VPNs, because it seamlessly integrates carrier and customer networks, works with carriers' existing infrastructures, is simple to provision, and offers massive scaleability, particularly in routed networks.

Using VPLS, for instance, customers can connect multiple sites over a provider-managed IP/MPLS network. All sites using VPLS appear to be on the same LAN, regardless of their location. More importantly, VPLS uses the ubiquitous Ethernet protocol as the customer handoff, simplifying the LAN/WAN boundary and allowing for rapid and flexible service provisioning.

Despite all this, the road to VPLS deployment is anything but straight and narrow. The standard has been in development for the last two years, but the technology is dependent on the rollout of Ethernet services. What's more, vendors are wrestling over the best methods of implementation.

Products, which are just starting to roll out, conform to one of two drafts: Lasserre-V.Kompella and Kompella. In a scenario typical of all great standardization efforts, there's lots of drama, as a cast of characters that includes two brothers ranged on opposing sides (see Kompella vs Kompella) debates issues of scaleability, device discovery, and signaling.

On one side are the majority of vendors, which are adopting the Lasserre-V.Kompella draft. This list includes:

On the other side, implementing the Kompella draft (which many of the aforementioned vendors helped author) is Juniper Networks Inc. (Nasdaq: JNPR).

Going it alone is quite a gamble for Juniper, but the vendor was one of the first players to develop VPLS technology -- and once you head down a certain path, it’s hard to reverse course. Juniper argues that it's making provisions to back both technologies in its equipment.

Who will win? Who will lose? The stakes are clearly delineated in the 18-page Optical Oracle report, which describes in detail what VPLS is, how its two key drafts compare with each other and other technologies, and what differentiates the protocol. One section provides a detailed product assessment and financial analysis of leading vendors as a basis for handicapping the market.

"VPLS Variations" is available for sale here. A single-user subscription to the single report is $400. An annual subscription to the service, which costs $1,250, grants a user access to this report as well as the entire archive of past Optical Oracle Research -- and any new reports for the next 12 months.

— Mary Jander, Senior Editor, Light Reading

Editor's note: Light Reading is not affiliated with Oracle Corporation.