In the voice world of fixed channels and circuits, the absolute predictability of SONET bandwidth was not only reassuring, it was necessary. Voice needs an efficient packing of circuits in exact multiples of 64kbps, especially one that scales mightily and provides failure protection.
In the data world, SONET is anything but efficient, wasting megabits of transmission space because the unpredictable bandwidths of data flows don't fit the SONET mold. That deficiency was never more exposed than when DWDM moved into the metro space. Now, rather than just having underutilized SONET multiplexes, carriers had whole waves that were not used to their potential.
For the long-haul carriers, it is more economical for them not to burn waves by putting on a single signal, but to try to pack in as much as they can, up to the full 10 gigs. --Voltaire Cacal, senior analyst, Ryan Hankin Kent Inc. |
Now, a number of small startups are introducing DWDM metro products, which many of them term multiservice provisioning platforms. They not only provide a rich variety of data alternatives to SONET, but claim to do it more efficiently and cheaply than existing solutions. Also, Lucent Technologies Inc. (www.lucent.com) has introduced a high-speed optical networking system aimed at local networks and ISPs.
"The need in the metro market is real," says Voltaire Cacal, senior analyst, Ryan Hankin Kent Inc. (www.rhk.com). "It needs transparent optical networking, bit-rate independence or protocol independence on each wavelength. This has been a big selling point in the metro market because there we see more different bit rates and more varied services compared to the long haul."
Alidian Networks Inc. (www.alidian.com) announced April 3 its Optical Service Network (OSN), a family of digital cross-connects for metro DWDM that operate in ring or mesh topologies to deliver flexible bandwidth for multiple services. The OSN uses two new technologies: WavePack, which creates multiprotocol waves with services such as IP, ATM, Ethernet and TDM, all running in native mode; and WaveMux, a transport that scales from a single OC-48 to dozens of OC-48s. The system's WaveSwitch can move traffic from one wavelength to another and can drop services from wavelengths without disturbing the rest of the payload.
"We are in the metro gap between the long-haul networks and access network," says Ted Rado, director of marketing, Alidian. "The metro gap today is built on SONET, which is optimized for voice." Rado says the cards used to enable the Alidian system to drop and add services are less costly than in other platforms, and the company's cross-connects will be half the price of long-haul-oriented products from Sycamore Networks Inc. (www.sycamorenet.com) and Tellium Inc. (www.tellium.com).
Others introducing new products include Astral Point Communications Inc. (www.astralpoint.com), which unveiled its ON 5000 on March 6. Also a meshed DWDM-based metro product, the Astral Point product will switch services or aggregate T1 traffic onto optical networks. Bill Mitchell, vice president of marketing, describes the network as based on intelligent optical nodes that "are peer level nodes that communicate with each other, unlike digital cross-connects that do not communicate, but just make connections." Advanced TelCom Group Inc. (www.atgi.net) has signed a beta test agreement with Astral Point Communications to test the ON 5000 Optical Services Node within ATG's networks.
Also in this space are Appian Communications Inc. (www.appian.com), which announced its formation in January; Chromatis Networks Inc. (www.chromatis.com), which announced product in March; Mayan Networks Corp. (www.mayannetworks.com), which announced products early in February; and Sirocco Systems Inc. (www.siroccosystems.com). Most are still at the beta test stage or have not yet introduced technology. "Because they are smaller, they are able to address the market more quickly and in a more focused way," says Cacal.
Although some of these companies emphasize their ability to put multiple services in a wave, "most LECs want to see waves as independent, so they put all their IP on one and SONET on another and ATM on another," Cacal says.
"For the long-haul carriers, it is more economical for them not to burn waves by putting on a single signal, but to try to pack in as much as they can, up to the full 10 gigs."
If the equipment turns out to be as cheap as advertised, service providers will adopt it for access, Cacal says, because they do not want to have to manage services at the backbone, but just at the incoming terminal.
The Lucent Wave- Star Data Express 10G, the newest entrant into Lucent's WaveStar family, is optimized to carry IP traffic in a local or regional network at speeds up to 10gbps (OC-192). Lucent claims the products provide a 60 percent cost savings.
Adding a 10gbps product in the local arena means Lucent can offer end-to- end transmission at this high data rate, across long-haul and metro networks.
Metromedia Fiber Networks Inc. (www.mmfn.com) will trial the new product first in the network that connects its Palo Alto Internet Exchange (PAIX) with other exchange sites in the San Francisco Bay area.
