Quantum Bridge?s Optical Access System lets carriers bring serious bandwidth to small and midsize businesses without deploying new fiber.
by Doug Allen
OPTICAL ACCESS SYSTEM
Occasionally, the major telecom pundits (who generally don?t agree on the value of convergence, much less new product announcements) all unite behind a new technology or implementation. This harmonic convergence doesn?t come often?(I think Multiprotocol Label Switching [MPLS] was the last example)?so when it does, let?s savor it and take a look at the recipient of this positive attention.
Optical networking start-up Quantum Bridge ( www.quantumbridge.com ) has come up with an impressive Central Office (CO) and Customer Premises Equipment (CPE) suite called the Optical Access System (OAS). Early boosters include Tom Nolle at CIMI, the Yankee Group, Vertical Systems, Pioneer Consulting, and Current Analysis, among others.
Why all the love? Because with OAS, carriers can use existing fiber optic cable to bring serious bandwidth to small and midsize businesses, a traditionally underserved market. That bandwidth can be scaled from 1Mbit/sec to 100Mbits/sec and charged for accordingly. Essentially, Quantum Bridge is bringing fiber access closer to the customer, much the way fiber to the curb was supposed to work before its low-yield profit ratio slowed deployment.
OAS bridges the CO and CPE with Passive Optical Networking (PON) technology that eliminates deployment-killers such as expensive outside-plant active network elements. A PON system costs less because it only requires devices at the node and at the customer premises to switch and translate the optical traffic: Termination costs are estimated to run a tenth that of ring technology. That makes fiber to the business a much more profitable bid for carriers, while business customers can get access that meets their needs as traffic demand grows. It is hoped (though it remains to be seen) that the carrier savings will be passed on to the customer.
The suite also uses the vendor?s proprietary Dynamic Wavelength Slicing (DWS) protocol. This lets traffic destined for multiple end points share a single wavelength, so carriers can appropriately divvy up a channel based on the applications and QoS required. This flexibility and depth of bandwidth provisioning make the system?s management capabilities that much more critical.
The OAS also includes an integrated element management system with service provisioning, fault and performance management, and software administration capabilities for Service Level Agreement (SLA) guarantees.
?Quantum Bridge?s solution is unique and hard to replicate for the competition,? says John Freeman, vice president of research at the Fearless Group ( www.fearlessgroup.com ). ?For a service provider that has a fiber optic infrastructure in a dense urban area, the OAS will maximize revenue off this fiber and target a much broader market for high-speed access. This cannot really be done today with existing Dense Wave Division Multiplexing [DWDM] or SONET technologies.?
Case in point: Comcast ( www.comcast.com ), a broadband service provider for all traffic types, has bought the OAS (commercially available in the second quarter of 2000) with plans to more fully utilize some of its unfilled, stranded fibers that happen to pass businesses. Comcast intends to offer Ethernet and DS1 voice and private line services with incremental builds of the embedded Hybrid Fiber Coax (HFC) network. Another application, Freeman points out, is as a feeder to multitenant, unit-based access pipe that uses in-building copper for the final link to the subscriber.
So what does this system look like? The QB100 Intelligent Optical Terminal (see Figure 1) sits at the customer premises and supports 10/100 Ethernet, Time Division Multiplexing (TDM), ATM, and frame relay DS1 interfaces (and more are on the way). Hundreds of these terminals can be carried on the QB5000 Optical Access Switch (see Figure 2), a CO switch that aggregates the incoming QB100 traffic located downstream. The switch offers an OC-12c trunk, a redundant 5Gbit/sec IP and ATM switching fabric, packet and ATM over SONET, ITU, DWDM, and Gigabit Ethernet that can interoperate with legacy equipment. The 15-slot chassis can support more than 200 businesses and scale up to 800 businesses. Distances can run up to 20 kilometers at 622Mbits/sec.
One caveat: PON may be less expensive and less complex than active elements, but deployment will likely require unique skills that are currently unfamiliar to many technicians. |
