ROADM Map

The notion of that sort of mesh/ring mix was at the heart of Meriton Networks' recent acquisition of Mahi Networks, which turned to the ROADM market through its own acquisition of Photuris after its own homegrown product (a large transport platform) failed to catch on. Meriton and Mahi said they often found themselves in competition with each other for the business of large incumbent carriers that wanted a mix of mesh and ring topologies. Both Meriton — whose gear is optimized for mesh networks — and Mahi — whose gear is optimized for rings — were forced to offer prospective customers future products that covered the other bases. Finally, they decided to combine their efforts. By next year, the gear will be integrated with a common management system.

“Meshes are problematic because to make meshes work, you use routers,” Holliday said. “The problem with that is routers are slow.”

Though mesh networks can't keep up with Sonet's 50 ms reflexes, he said, meshes are advantageous in that they allow carriers to switch more granular traffic streams inside the wavelength itself instead of having to switch only the entire wavelength.

Other vendors are forwarding their own unique approaches to ROADM, adding variety and differentiation to the sector. Early next year, Ciena will introduce what it calls “dynamic wavelength routing” — a combination of WSS and sub-wavelength grooming, which allows operators to groom more granular slices of bandwidth (in Ciena's case, 155 Mb/s), perhaps even individual services. Ciena calls dynamic wavelength routing “the third-generation ROADM.”

One vendor is even taking on the ROADM market with non-ROADM technology. Infinera's optical switch uses integrated photonics to avoid the high cost of components that translate optical signals into electrical ones and back again. Though not a ROADM, the company competes against ROADM vendors and serves applications that ROADMs would, such as the nationwide deployment along Level 3 Communications' backbone announced earlier this year. Perhaps hoping to take his fair share of ROADM buzz as well, Infinera's marketing director Rick Dodd said he's often tempted to call his company's technology “READM,” substituting the word “electrical” for “optical.” For an equipment vendor as unique and innovative as Infinera to consider describing itself as a ROADM sound-alike is perhaps one more testament to the power of its popularity.