Corrigent Comes Out

WASHINGTON, D.C. -- Yet another vendor touting resilient packet ring (RPR) technology is aiming to make a splash at the Comnet tradeshow today, with a live demo of 10-Gbit/s Ethernet metro gear achieving sub-50-millisecond restoration times (see Corrigent Demos 10-Gig RPR).

The company, Corrigent Systems is showing its CM-100 transport platform for the first time. The box carries Ethernet traffic while also providing the full range of existing TDM (time-division multiplexing) and Sonet-based services at 10 Gbit/s, according to Corrigent, which claims that it can do this for half the cost of alternative solutions.

What differentiates Corrigent’s new product from the dozens of other players in the RPR market is that the product supports a full implementation of Sonet and is specifically designed to help tier-one service providers migrate their networks from circuits to packet networks.

Other solutions like those from Lantern Communications Inc. and Luminous Networks Inc. are based on Ethernet, while Cisco Systems Inc. (Nasdaq: CSCO) uses RPR for its router interfaces. But Corrigent has taken a different approach. It uses Sonet as the physical layer to take advantage of the timing mechanism inherent in the Sonet protocol. This allows the sub-50-millisecond restoration. Then it uses the RPR MAC for resilience, with Ethernet or another packet service layered on top.

Unlike other solutions that carry Ethernet over Sonet, Corrigent is not encapsulating the Ethernet traffic. Instead, it is able to carry native Ethernet over RPR over Sonet, making for more efficient use of bandwidth, says Gady Rosenfeld, director of strategic marketing for Corrigent.

It’s the use of the Sonet physical layer in combination with RPR that allows Corrigent to carry time-sensitive and jitter-sensitive traffic like voice and also allows the device to be deployed within a Sonet infrastructure. As a result, the company asserts, service providers can have all the features of Sonet without allocating a spare fiber for protection. Rosenfeld says it can save providers anywhere from 50 to 80 percent on operating costs.

“A lot of the players have been pushing a next-generation approach,” says Dave Dunphy, an analyst with Current Analysis. “But Corrigent doesn’t seem to be taking that tack. They’re offering a transition by supporting a broad range of traffic types.”

But Corrigent isn’t the only RPR vendor claiming to have the flexibility to handle Sonet/TDM traffic. Luminous Networks Inc. also supports Sonet/TDM traffic. Luminous differs from Corrigent in two main ways. One, its architecture does not use the Sonet physical layer; it uses Ethernet. Second, it only handles 2.5-Gbit/s rings in its current version, whereas Corrigent handles 10-Gbit/s rings with an architecture that scales to 40 Gbit/s.

”Ten Gbit/s is certainly an important factor,” says Dunphy. “It’s starting to become more and more important to providers.”

While Corrigent may outperform Luminous on speeds and feeds right now, Luminous has one big advantage over Corrigent. It is actually shipping its product to real live customers. Cox Communications Inc. (NYSE: COX) is deploying the Luminous product under the Scientific-Atlanta Inc. (NYSE: SFA) label. Luminous also announced earlier this month that China Netcom Corp. Ltd. has deployed its PacketWave in nine cities, with three city rollouts planned for later this year (see Chinese Get Luminous). Corrigent’s CM-100 hasn’t even shipped for beta testing yet.

Corrigent executives say it should be ready for general availability no later than the middle of this year. And unlike other RPR companies, which are still working out the terms of certification with Telcordia Technologies Inc., Corrigent claims it will be fully Osmine compliant by September of this year.

Corrigent, like startups Luminous and Lantern, has been very active in the RPR working group, helping draft the Darwin proposal that was recently accepted by the group (see RPR Moves Forward). This trade show marks the first time the company has exhibited in public (see Corrigent Joins Metro Ethernet Mix).

— Marguerite Reardon, Senior Editor, Light Reading
etherguy 12/4/2012 | 11:00:55 PM
re: Corrigent Comes Out corrigent is under-funded and the vcs won't touch it because it's too far behind luminous and even lantern which has a 10-gig product almost ready for trials. the company was spun out of orckit and when's the last time you saw a successful spinout of an isreali company? it happens but not very often.

the market isn't ready for 10 gig in any other application other than aggregation and core switching. maybe they'll line up some trials but they are 6-9 months away from shipping and by then lantern (if they get their act together and deliver something that works) and luminous will have a solid 18 months in luminous' case and about 8 months in lantern's case, lead.

these guys are d.o.a. unfortunately. orckit should spin it back in (they probably will).
William F. Letcher 12/4/2012 | 11:00:52 PM
re: Corrigent Comes Out Unlike other solutions that carry Ethernet over Sonet, Corrigent is not encapsulating the Ethernet traffic. Instead, it is able to carry native Ethernet over RPR over Sonet, making for more efficient use of bandwidth, says Gady Rosenfeld, director of strategic marketing for Corrigent.

um, not sure I understand exactly how this makes more efficient use of bandwidth.

but I do think the concept of an evolutionary approach will win out over that of an evolutionary one to carrier migration from TDM to packet based networks. making SONET (specifically synchronization, framing, etc) the underlying transport mechanism was the right move, there's too much SONET out there now. but I question the encapsulation method - not even sure I understand it as explained in the article.

once again, this is great for ethernet and data traffic but if luminous, lantern, corrigent or anyone else thinks any legitimate carrier is going to deploy a TDM over ethernet over RPR architecture for voice/TDM transport, they've been smoking too much weed.

BBBoa 12/4/2012 | 11:00:49 PM
re: Corrigent Comes Out Sounds good, but carriers are not deploying Ethernet at 10 Gig - they're barely deploying Ethernet at 1 Gig. Carriers are deploying DS-3 and OC-n services because that's what they know from an operational support perspective and that's what their salespeople know how to sell.

Corrigent will be successful if their funding can sustain them long enough to realize their vision - while holding off Luminous, Lantern and a host of others in their space. My bet is that they are betting on a big player to swoop in, gobble them up and cash out.
fundamental_guy 12/4/2012 | 11:00:47 PM
re: Corrigent Comes Out
When carriers are filling for chapter 11 having
spend all their cash on BW they still lack services
to turn their "BW assets" into revenues.

Most MANs have some sort of heirarchy: access rings connected to metro core rings with mega-pops
on the core rings. The collector-hubs that
connect these access rings to core aggregate data to one entity at the metro-pop while aggregating TDM to another entity at either the same pop or another one. Hence, very little BW sharing happens on metro core rings. In fact BW sharing provides
very little visibility for capacity planning in
the metro core.

What makes more sense for carriers is to deploy
RPR in the access rings and use traditional
multiservice-sonet gear in the core. Access rings
are dominantly 2.5 gigs.

Corrigent is barking up the wrong tree of
combining RPR with 10 gigs. Lantern did and now
finds no more lamp-oil to keep its lantern lit.
Often pragmatism takes over technology ecstacy.
Further, one will sell more boxes focused on
access rings rather than metro core rings.

So what next? Orkit -> Corrigent -> ???
veemee 12/4/2012 | 11:00:44 PM
re: Corrigent Comes Out Are any of the BIG guys deploying RPR(or are only China and India the only major markets)?

Who is CISCO referring to when it says it has already a 100k ports deplayed?
mjm 12/4/2012 | 10:59:12 PM
re: Corrigent Comes Out It seems this solution isn't much different from NT's. They have Sonet gear with RPR, they have 50 msec failover, and I am told they have been doinig it for over a year.... Not to mention they are already in the Carriers.

The only thing I see different is the BW, and how long before they increase that....

What am I missing?
Sign In