100G Ethernet

Comcast Thinks Big

2:00 PM -- While I've never been to the SCTE Cable-Tec Expo, it sounds like the proper venue for cable operators to talk big about technology. Comcast Corp. (Nasdaq: CMCSA, CMCSK) seems to be taking advantage of that today, talking up the biggest routers from Cisco Systems Inc. (Nasdaq: CSCO) and Juniper Networks Inc. (NYSE: JNPR).

It's old news that Comcast has deployed Cisco's CRS-1. (Actually, it's even older news.) Today, the operator is announcing a live test of 100-Gbit/Ethernet on the router, though. (See Comcast, Cisco Test 100-Gig.)

It's the second test of 100-Gbit/s that we've seen in a couple of weeks, as Avago Technologies Pte. , Infinera Corp. (Nasdaq: INFN), Ixia (Nasdaq: XXIA), and XO Communications Inc. teamed up for a demo at NXTcomm. (See 100-Gig Demo.)

Perhaps in the interest of equal time, Comcast is also saying it's ordered "additional Juniper Networks MX-series Ethernet Services Routers and T1600 core routers." (See Comcast Deploys Juniper.) I think the "additional" part refers to the MX, which Comcast says it started using a year ago, and not to the T1600. Come to think of it, I wasn't aware Comcast was using the T640.

I'll be talking with all the parties involved, seeing if there's a more complete story I can build up here.

— Craig Matsumoto, West Coast Editor, Light Reading

Pete Baldwin 12/5/2012 | 3:37:43 PM
re: Comcast Thinks Big (I deleted the previous version of this message and am reposting it. Call it an occupational perk.)

The test was using StrataLight's transponder chassis. Similar to the Avago / Infinera / Ixia / XO test from last week, it used multilane distribution (MLD) to stripe 10x10Gig wavelengths from the Cisco CRS-1 to the StrataLight box. It sounds like StrataLight then sent a single wavelength, using a modulation scheme they don't want to specify, to send the signal 300km.
AutoDog 12/5/2012 | 3:37:43 PM
re: Comcast Thinks Big Whose DWDM transport gear did Cisco & Comcast use to carry this 100GE traffic between cities? Was it over a single lambda?

^Eagle^ 12/5/2012 | 3:37:43 PM
re: Comcast Thinks Big Pretty sure it was Stratalight.

Note; this from common knowledge on the street about who is upgrading Comcast's backbone to 40G and who is Cisco's OEM for 40G solutions and from the recent announcement that Stratalight has developed 100G electronics to drive the lambda's.

Also pretty sure it was over a single wavelength. Don't know the modulation format, but probably DQPSK or Pol-DQPSK.


Stevery 12/5/2012 | 3:37:42 PM
re: Comcast Thinks Big sailboat: Also pretty sure it was over a single wavelength. Don't know the modulation format, but probably DQPSK or Pol-DQPSK.

That is what I would have guessed as well, but I would lean towards Pol-DQPSK: Given the size of the market + how much money they have already burned would make recovering the R&D costs of 50G electronics a tough business. 25G would require much less investment.

The interesting thing to me is that they did not want to reveal the modulation format. It probably means that either:

1. We're wrong (the above are obvious guesses), they're using something else
2. They have patent infringement worries.

In any case, props to the tech team for making this work. None of this crap is easy.
farsonic 12/5/2012 | 3:37:39 PM
re: Comcast Thinks Big So the CRS1 was generating the traffic over 10x10GE links into a starlight chassis?

How is this worthy of a Cisco press release, seems to me that the starlight is doing the heavy lifting. Several vendors could transmit line rate 10x10Gb/s into such a chassis.

Props go to the DWDM chassis and the traffic generator :)

Pete Baldwin 12/5/2012 | 3:37:38 PM
re: Comcast Thinks Big The client interface wasn't a plain 10x10Gig; it was the first demonstration of the MLD interface -- which, yes, happens to be 10x10 but starts with a 100-Gig stream of packets. I guess what I want to stress is that (to my knowledge) Cisco didn't take 10 unrelated 10-gig streams and send them to the DWDM box independent of each other. The CRS-1 did have to do some "100-gig" work.

So yes, you could argue StrataLight deserves moreof the credit, but Cisco still lays claim to the first pre-standards-based client interface for 100GE. As press releases go, they've done more with less.

Some additional details/trivia here:
Sign In