& cplSiteName &

Reconfigurable Optical Add/Drop Multiplexer (ROADM)

Craig Matsumoto
The Buzz Bin
Craig Matsumoto

An all-optical switching element for adding wavelengths to (and dropping them from) a DWDM stream.

The ROADM provides a way to do this in the optical domain, without having to terminate the traffic. More significantly, ROADMs gave carriers a way to nail up these wavelengths by only making changes at the endpoints. Previously, adding a wavelength meant manually configuring every node the wavelength was going to pass through.

ROADMs have room for improvement. For example, the configuration at those endpoints still has to be done manually. But they've become an integral part of the optical network.

ROADMs are deployed as modules -- cards slotted into optical transport equipment. They've become elemental to packet-optical transport systems (P-OTS). (See Optical's Packet Magic.) Sam Lisle of Fujitsu Network Communications Inc. explains as much in this 2008 video.

The heart of a ROADM is a Wavelength Selective Switch (WSS). WSSs are commonly available in sizes up to 1x9 -- capable of adding or dropping eight wavelengths. (The ninth is the "express lane" fiber that goes straight out of the ROADM, for traffic that doesn't need to be terminated at that node.)

The next large step could be a 1x23 WSS, which some companies began showing in 2010. (See ROADMs Get Sized Up and OFC/NFOEC: ROADM Roundup.)

This JDSU (Nasdaq: JDSU; Toronto: JDU) custom video from early 2010 notes the size trends in ROADMs -- and the possibility of going colorless and directionless, which we'll outline next.

Colorless, directionless, contentionless, gridless
Vendors would like ROADMs to be more automated. As Glenn Wellbrock of Verizon Communications Inc. (NYSE: VZ) put it in May 2010, an ideal feature would be a big "defrag" button that resets the network to its optimal state. (See Verizon: Give Us More Flexible ROADMs for 100G.)

Here's what they're asking for:

  • Colorless: Able to send any wavelength to any port, and to change these assignments automatically.

  • Directionless: Allowing output ports to send traffic in any direction.

  • Contentionless: Allowing one ROADM port to use a wavelength that got dropped by another port. This could be accomplished with an NxN switching element. Large all-optical switches, of sizes up to 768x768, could also play a role here. (See OFC/NFOEC 2009 Preview and Calient Gets Ambitious With Optical Switching.)

  • Gridless: Some carriers think they'll want ROADM to assign wavelengths off of the International Telecommunication Union (ITU) grid. When Terabit Ethernet gets invented, for example, it might be easiest to let it occupy two ITU grid spaces, or 1.5, or some other arbitrary proportion. (See OFC/NFOEC: For ROADMs, Less Is More.)

Here's a 2010 video where Wellbrock goes over these issues.

The business
As of 2009, JDSU was the market leader in ROADM components, with Finisar Corp. (Nasdaq: FNSR) coming on strong as a competitor. (See Finisar Climbs ROADM Ranks.)

Recent acquisitions and partnerships related to ROADMs:

Finisar CEO Jerry Rawls explains the Nistica deal at the end of this video, from OFC/NFOEC 2008.

(7)  | 
Comment  | 
Print  | 
Newest First  |  Oldest First  |  Threaded View        ADD A COMMENT
User Rank: Light Beer
8/16/2016 | 6:04:08 AM
I want to use ROADM but which service provider will best.

Zaful Coupons
User Rank: Light Beer
6/10/2016 | 8:25:13 AM
To easy to do
To easy to do this stuff visit my web address t fine out some more..
User Rank: Light Beer
4/17/2016 | 1:55:26 PM
Its very hard to reconfigurable  optical add.If you have know knowledge about that please dont do that.Use any specialist.


Coquitlam counselling Bc
User Rank: Light Beer
1/21/2016 | 3:23:11 AM
fb online
this is the tool for generator of hacker facebook that can give you fb account online.
User Rank: Light Beer
6/9/2015 | 6:13:00 AM
The consecutive falling of two waves will create nodes where the frequency will be zero. The ROADMs has provided the option to change the frequency manually. To get it automatically it has to follow aussie essay which has the leads to do it.
User Rank: Light Beer
12/5/2012 | 5:09:26 PM
re: Reconfigurable Optical Add/Drop Multiplexer (ROADM)


Just read a portion of your story of new products at OFC.  When reading the ROADM portion, I did not see any "new" news.  Only old news.  ather it was a summary of actions in the ROADM space and stories in 2009 / 2010.  I mistakenly assumed this story was to have new content and to be about new announcements at OFC 2011.


User Rank: Light Beer
12/5/2012 | 5:06:01 PM
re: Reconfigurable Optical Add/Drop Multiplexer (ROADM)

Too too old news!

Light Reading’s Upskill U is a FREE, interactive, online educational resource that delivers must-have education on themes that relate to the overall business transformation taking place in the communications industry.
Friday, October 21, 1:00PM EDT
Security: Evolving the Data Center
Rasool Kareem Irfan, Head, Telecom & Infrastructure Security Practice, Tata Communications Transformation Services Ltd (TCTS)
Wednesday, October 26, 1:00PM EDT
Security: Tackling DDoS
Gary Sockrider, Principal Security Technologist, Arbor Networks
Friday, October 28, 1:00PM EDT
Security: The Plusses and Minuses of Open Source Software
Nick Feamster, Acting Director, Center for Information Technology Policy, Princeton University
Wednesday, November 16, 1:00PM EST
SDN 101
in association with:
From The Founder
Light Reading today starts a new voyage as part of a larger Enterprise.
Flash Poll
Live Streaming Video
Charting the CSP's Future
Six different communications service providers join to debate their visions of the future CSP, following a landmark presentation from AT&T on its massive virtualization efforts and a look back on where the telecom industry has been and where it's going from two industry veterans.
LRTV Custom TV
Next-Generation Technology Beyond DOCSIS 3.1

10|20|16   |     |   (0) comments

At SCTE 2016, Huawei's Liu Jianhua speaks with Alan Breznick for an exclusive interview.
LRTV Custom TV
Hybrid Video Solutions to Change TV, Change Future

10|20|16   |     |   (0) comments

At SCTE 2016, Huawei's Ian Locke speaks with Alan Breznick for an exclusive interview.
LRTV Custom TV
Huawei Future-Oriented Giga Coax Network

10|20|16   |     |   (0) comments

At SCTE 2016, Huawei's Allen Wang speaks with Alan Breznick for an exclusive interview.
LRTV Custom TV
Huawei at SCTE 2016

10|20|16   |     |   (0) comments

Join Alan Breznick of Light Reading and take a sneak peek at the Huawei booth at SCTE 2016.
LRTV Custom TV
Assuring Network Quality in a Rapidly Changing Environment

10|20|16   |     |   (0) comments

As the rate of change and complexity increases in agile networks, the importance of introducing DevOps methodologies for integrating active test and assurance solutions throughout the full service lifecycle becomes critical to ensure that customers are experiencing the service quality they demand. The industry landscape is changing, and software-based test and ...
Telecom Innovators Video Showcase
A10 Networks on Service Providers' Industry Needs

10|20|16   |     |   (0) comments

Light Reading's Steve Saunders hears how A10 enables service providers to accelerate, secure and optimize their application delivery to drive down costs, enhance service availability, and better respond to customer requirements, so they can improve customer satisfaction, monetize their network, and grow revenues.
LRTV Custom TV
New NFV Use Cases for Cable TV

10|19|16   |     |   (0) comments

A large number of NFV use cases are focused on the enterprise domain, looking at virtualization of customer-premises equipment (CPE). To date, there has been little focus on the use cases and business case for virtualization of the video content delivery networks required to deliver unicast and streaming video to consumers. Amdocs commissioned Analysys Mason to ...
Women in Comms Introduction Videos
Meet the Future Workforce: New Faces, Expectations & Motivations

10|19|16   |   5:33   |   (1) comment

Millennials and their younger peers, Gen Z, expect more out of their network and more out of their work. Intel's Lynn Comp shares how the industry can prepare for this new generation of workers.
LRTV Custom TV
ZTE Global Services User Congress 2016 Highlights

10|19|16   |     |   (0) comments

ZTE held its 2nd Global Service User Conference in Dusseldorf on October 13-14. Representatives from network operators, leading industry analysts and ZTE senior expertsattended the event, exploring the best practice in managed services and the vision to transform network operations into the operations center of the future (OpCF) in the software-defined networking ...
LRTV Custom TV
Cliff Grossner on Cloud & Network Synergy From Carrier Service

10|18|16   |     |   (0) comments

Local carriers offer the collaborated cloud and network service that benefits from their understanding of the regulations operating in different vertical markets.
In this interview, Cliff Grossner from IHS Technology talks about how this advanced service can support business agility and flexibility.
LRTV Custom TV
VeEX: Live from SCTE Cable-Tec Expo 2016

10|17|16   |     |   (0) comments

Cyrille Morelle, VeEX's President and CEO, talks with Light Reading's Alan Breznick live from the SCTE Cable-Tec Expo 2016. They discuss DOCSIS 3.1 technology, deployments and early lessons learned. New products on display include the CX350s-D3.1, CX380s-D3.1, CX310, AT2500-3G, FX150 OTDR and MTT WiFI Air Expert.
LRTV Custom TV
Smith Micro's Carrier-Grade WiFi Component

10|17|16   |     |   (0) comments

Join Carol Wilson of Light Reading as she interviews the CTO of Smith Micro, Dave Sperling.
Upcoming Live Events
November 3, 2016, The Montcalm Marble Arch, London
November 30, 2016, The Westin Times Square, New York City
December 1, 2016, The Westin Times Square, New York, NY
December 6-8, 2016, The Westin Excelsior, Rome
May 16-17, 2017, Austin Convention Center, Austin, TX
All Upcoming Live Events
Hot Topics
Verizon Wants More Data on Yahoo Breach
Alan Breznick, Cable/Video Practice Leader, Light Reading, 10/20/2016
US Issues Total Flight Ban on Samsung Note 7
Dan Jones, Mobile Editor, 10/15/2016
Oh Snap! Qualcomm Unveils X50, Its First 5G Modem
Dan Jones, Mobile Editor, 10/17/2016
SDN Champions ONF & ON.Lab Tie the Knot
Carol Wilson, Editor-at-large, 10/19/2016
Telecom Italia Plots Digital 'Overlay,' Not Transformation
Iain Morris, News Editor, 10/17/2016
Like Us on Facebook
Twitter Feed
BETWEEN THE CEOs - Executive Interviews
Join us for an in-depth interview between Steve Saunders of Light Reading and Alexis Black Bjorlin of Intel as they discuss the release of the company's Silicon Photonics platform, its performance, long-term prospects, customer expectations and much more.
There's no question that, come 2020, 5G technology will turn the world's conception of what mobile networking is on its head. Within the world of 5G development, Dr. ...
Animals with Phones
Live Digital Audio

A vital part of increasing the number of women in comms is transforming the ways companies can support and empower women. While progressive company policies that support both men and women in achieving work-life balance are a step in the right direction, creating a company culture that supports those policies can at times be more challenging.

During this show, we'll talk to Lynn Comp, Senior Director of Industry and Sales Enabling (ISE) in the Network Platforms Group at Intel, about why those challenges exist and how companies can overcome them. She'll provide insight into how Intel has worked to create a culture that supports work-life balance, and provide steps and guidance for other companies wishing to do the same. We will also leave plenty of time to get your questions answered live on the air.