Optical/IP Networks

Grooming Switches: Key Requirements

The market for just about everything to do with optical networking is in the dumps right now, but when carriers start spending again, the chances are that grooming switches will be high on their shopping lists.

Why? Because grooming switches hold out the promise of solving a lot of problems for service providers:
  • They boost the capacity and improve the efficiency of the Sonet/SDH infrastructure that carries nearly all of their revenue-generating services.
  • They cut capital expenditure and free up space in crowded central offices by eliminating requirements for digital crossconnects and add/drop multiplexers.
  • They automate provisioning of circuits, which helps carriers respond to market demands faster and slash operating expenditures by reducing requirements for sending engineers into the field to configure equipment manually.

When carriers start spending again, however, the market for grooming switches will have changed considerably from what it was a year ago.

At that time, Ciena Corp. (Nasdaq: CIEN) was pretty much the only serious player. Since then, more than half a dozen vendors have brought products to market that compete with and possibly outgun Ciena's CoreDirector. And those vendors include many of the carriers' traditional suppliers – Alcatel SA (NYSE: ALA; Paris: CGEP:PA), Lucent Technologies Inc. (NYSE: LU), and Nortel Networks Corp. (NYSE/Toronto: NT), to name but a few.

So, now there's a good choice of grooming switches, how do you pick the best?

Good question. For starters, different switches might be better for different applications – and grooming switches can be used in a variety of ways in carrier networks, as this report will demonstrate.

Then there's the issue of comparing grooming switches, and right now, that often comes down to comparing marketing claims. Bearing in mind that grooming switches aren't cheap – they cost upwards of a $1 million each – this simply isn't good enough.

With such important equipment, comparisons need to be based on something much more solid: performance measurements undertaken by an impartial laboratory. They also need to be undertaken on a meshed network of switches – the closest thing possible to real-life conditions in a carrier environment – not on a single box.

This is a challenging task, but it's what Light Reading is aiming to accomplish with its blockbuster test of optical grooming switches, announced in March (see Light Reading Announces Switch Test).

Light Reading has commissioned BTexact Technologies to design and carry out these tests. As the advanced research and technology business division of British Telecom (BT) (NYSE: BTY), BTexact has a long history of determining requirements and evaluating equipment for a big carrier. BTexact will use the leading-edge OC48/STM16 and OC192/STM64 Sonet/SDH test and measurement equipment from Agilent Technologies Inc. (NYSE: A) to undertake the tests.

This report establishes the foundations for our planned test. It's written by Trevor Brown, principal consultant, and Russell Davey, head of optical systems research, at BTexact. And it sets out the "big carrier" view of key requirements for grooming switches.

This forms the basis of the detailed test plan for Light Reading's project. The next step will be to invite vendors to participate in the test, which we hope to do in the coming week. They will be given an opportunity to comment on the test plan before a final version is frozen in late June, with a view to starting tests in late July. We hope to publish the results in October.

This is a big undertaking, not only for Light Reading and BTexact but also for participating vendors. Participation is free of charge (Light Reading is picking up the tab), but vendors will have to build miniature networks of their equipment in BTexact's laboratory at their own expense.

On the other hand, there's a lot to play for here. This is the first ever serious test of optical switches, and it's being carried out in a rigorously fair and professional manner by the research arm of a major carrier. The results are bound to be taken seriously by other carriers and are likely to have a profound influence on the future market for grooming switches – a market that promises to be worth many billions of dollars (see Optical Crossconnects Surging).

Other carriers have a role to play here. They should encourage their suppliers to participate in this test, which will help them save time when short-listing grooming switches for evaluation.

Carriers should also question the motives of vendors that decline to go head to head with competitors in Light Reading's test. A little pressure can be applied by pointing to the results of a recent Research Poll on Light Reading. In the poll, taken by 134 people, respondents were asked for the most plausible reason for a vendor declining to participate in a free test:

  • 39 percent checked "vendor knows that it won't do well in the test."
  • 21 percent checked "vendor wants to discourage comparisons with competing products."
  • 19 percent checked "vendor doesn't have the resources to support the test," which calls into question whether it would have the resources to support the deployment of a far greater number of switches in a real-life project.
  • 16 percent checked "vendor doesn't have a product that's ready for commercial use."
  • A mere 4 percent checked "vendor can't spare equipment for the test."

As already noted, this report covers the first step in Light Reading's test – the definition of key carrier requirements for grooming switches. Here's a hyperlinked summary:


  • What is an optical grooming switch?
  • Why test them?

Common Applications

  • Five typical uses for grooming switches
  • How requirements differ with use

Reliability and Scaleability

  • Reliability
  • Scaleability
  • Performance

Feature Requirements

  • Interface standards
  • Architectural flexibility
  • Software stability

Management Requirements

  • Integration with existing OSS
  • Point-and-click provisioning

Control Plane Features

  • Need to support standards "as soon as practical"
  • Need to scale to more than 100,000 connections

Environmental and Accommodation Features

  • Heat dissipation
  • Power consumption
  • Footprint

Testing Scope and Principles

  • What will be tested
  • How it will be done

Introduction and background by Peter Heywood, Founding Editor,
Light Reading http://www.lightreading.com

About the authors: Trevor Brown is a principal consultant in the technology consulting division of BTexact Technologies. Russell Davey is head of optical systems research for BTexact. BTexact is the research and advanced technology arm of British Telecom (BT) (NYSE: BTY).

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Rock_On 12/4/2012 | 10:19:26 PM
re: Grooming Switches: Key Requirements LR, When do you plan to post the article with the details on your Carrier-class IP VPN Stess Test?
Steve Saunders 12/4/2012 | 10:19:01 PM
re: Grooming Switches: Key Requirements "LR, When do you plan to post the article with the details on your Carrier-class IP VPN Stess Test?"

Cheapseats 12/4/2012 | 9:47:27 PM
re: Grooming Switches: Key Requirements Are there any takers, did this test ever take go anywhere?
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