by Stephen Hardy
Len Bosack, a co-founder of Cisco Systems and current founder and chief executive of emerging optical equipment company XKL LLC (www.xkl.com), has a clear picture of his intended customers, mostly network managers at enterprises and ISPs.
“The problem for a lot of enterprise customers is these guys are perfectly good at running their corporate campus networks and their corporate WAN, but they’re terrified of anything optical,” he says. “And heaven forefend that they should have to manage something that uses TL1-that’s not something that they regard as a positive development.”
This perception of optical communications would appear to pose a challenge for any company hoping to sell WDM equipment. However, Bosack believes that the attributes of XKL’s new DXM Optical Transport System line will win over network managers who don’t know much about optical communications-and like it that way.
Bosack founded XKL in 1991 after leaving Cisco. The company originally developed computer input/output technology (with MCI and Digital Equipment Corp. among its customers) before turning its attention to telecommunications, according to XKL sales and marketing coordinator Michael O’Brien. Its first telecom products are aimed at enterprises, ISPs, and others with metro data networking requirements that only optical fiber can fulfill. Leased services, if they’re even available from the local carriers, can be expensive and inflexible, O’Brien says. That likely will tempt network managers to take advantage of dark fiber to create their own networks. However, many data network designers don’t have experience with optical power budgets, protection mechanisms, or the network management schemes most optical communications equipment employs, O’Brien says.
The DXM Optical Transport System platforms are designed to make optical equipment look, feel, and act as much as possible like the data networking hardware with which XKL’s target customers are familiar. “We designed this system so you can go into an enterprise or an ISP-anyone who types at a standard CLI (command line interface)-and drop it in front of them and they’ll figure it out,” O’Brien explains.
The product line consists of a series of 1RU boxes that provide Layer 1 WDM connectivity and path protection, the latter at speeds of less than a millisecond. They are designed to provide value, ease of use, and reliability. In the value category, the small package requires less rack space, cooling, and power than the optical systems large vendors typically offer. As for reliability, the platforms combine the rapid path restoration capability with redundant cooling and power mechanisms.
However, XKL has placed its primary focus on ease of use. “It’s system engineered to be a system component in their data network. We don’t want them to have to learn optical physics,” Bosack explains. The platforms don’t contain line cards and they use standard SFP and XFP transceivers. Users can program each box to accommodate a variety of channel counts and line rates via a standard CLI. The systems also can be managed with SNMP, rather than a proprietary network management system and graphical user interface.
The DXM line comprises transport terminals that operate on sub-bands of the C-band and “band combiners” that enable terminals to be stacked to accommodate denser channel counts on a single fiber. The DXM offering includes:
• DXM3: This platform offers 3-Gbit/sec multirate interfaces to accommodate Gigabit Ethernet (GbE), 1G/2G Fibre Channel, and OC-48 traffic. The DXM3-10 offers single-path transport of 10 channels per unit via 100-km DWDM optics. The DXM3-5R offers five-channel dual-path ring-protected capability per unit. When stacked, DXM3s can support up to 40 DWDM channels.
• DXMh: This more capable box combines 3- and 10-Gbit/sec multirate interfaces to handle 10GbE, 10G Fibre Channel, and OC-192 requirements. Like the DXM3, it comes in five-channel and 10-channel configurations. The 10-channel box provides single-path transport of six 3-Gbit/sec and four 10-Gbit/sec client channels per unit and supports a reach of 80 km. The five-channel box provides dual-path ring-protected transport of three 3-Gbit/sec and two 10-Gbit/sec client channels, also at 80 km. Both platforms scale to 40 total channels.
• DBC: The “DWDM band combiner” enables users to combine the capabilities of multiple transport platforms to accommodate large channel count requirements. The DBCa also provides the ability to add/drop a single DXM band. The DBCd supports a dual-path DXM combination, while the DBCs supports single-path combinations.
The platforms will accommodate ring, mesh, and point-to-point topologies, with an internal crossbar switch aiding both network architectural and protection flexibility. Along this line, the proprietary dual-path protection mechanism for ring networks illustrates the company’s drive for simplicity, Bosack says.
“You take the data from the front client port, replicate it, and you shoot it down two different lasers around the ring….You get to the receive end, the software makes a decision based on received power levels which way the switch goes, and then it goes out to the client there,” he explains. “It’s as dumb as grass.”
The DXM systems are in general availability, with two small deployments already announced, one an ISP in Los Angeles and the other a data services company in Washington State. Bosack hints that the announcement of a European deployment may arrive soon.
Based on a quote he provided for XKL’s use, Infonetics Research founder and principal analyst Michael Howard believes the company may be on to something. “The DXM opens up a new target market for optical equipment-enterprises that can use an optical network, but don’t know how to build and operate one. The DXM allows such enterprises to set up and operate an optical network in a fairly simple, easy-to-use, and cost-effective way,” he is quoted as saying. “If enterprises respond positively, then it’s natural that carriers will want to consider using the product line as well.”