Loving the Alien
The Easiest Way to Upgrade Your Optical Network
Another David Bowie song… this time leading to a topic which once was everybody’s darling, but never really took off. Yes, this is going to be a plea for deploying alien wavelengths in your network, either as a replacement or as an add-on… to save you a lot of time and money.
The concept is intriguing… the biggest material value of an optical network lies in its transponders, but a lot of work and quite some money goes into deploying amplifiers and ROADMs alongside the fiber route. Once deployed, optical networks often stay in use for a decade or even longer. During this timeframe the development of new solutions and services doesn’t stop. So at a certain point the network will either run out of capacity or won’t be able to transport new services due to missing interfaces.
Amps and ROADMs don’t care since they are able to boost and route any kind of information as long as it comes with the right frequency. And apart from the lost investment, exchanging them causes a lot of hassle, so why not just leave them in for another decade and only upgrade the terminals?
The biggest opponents of this strategy were the operations teams, partially for good reasons. You have terminals from vendor A and amps from vendor B and something goes wrong… who do you call? Despite of all ‘best of breed’ and ‘mix ‘n match’ messages, the most seamless, and supposedly, smoothest way of running networks is to use only a single vendor. No finger pointing, no interworking tests and no (lack of) network management integration… sounds good to operations, but comes with a high price tag and often a limited overall performance (and the insight that there’s no such thing as seamless, but there’s always finger pointing).
In days of shrinking margins despite ever increasing bandwidth requirements, that might be a luxury carriers need to move away from. Luckily, all these ‘open’ network stories have appeared at the right time. Time for a preconception re-check…
The advantages of introducing alien wavelengths are obvious: instead of ripping out a complete network, deploy some new P-OTS’, connect them to the filters, make sure that the new wavelengths don’t overlap with what's already there and you’ve turned your faithful 10G network into a new one, carrying 20 times the bandwidth per lambda via shiny 200G transponders. Even adding guard bands to minimize the risk of interference doesn’t spoil that business case, and old 10G channels can remain in place for as long as necessary. The ability to manage such a network end to end is a number one priority, which can be broken down into visibility of what's going on and the ability to troubleshoot in case something goes wrong. Let’s tackle them one by one…
All current network management systems have the ability to integrate 3rd party solutions and many carriers are running separate alarm correlation systems anyway. The whole industry is shaken up by a wave of open solutions, so extending the reach of a current NMS installation is ongoing anyway, since no one will exchange it just for the sake of installing something new. Adding a new system for the new terminals isn’t a huge effort, in many cases the use of element managers is sufficient as long as they are connected to an overarching system. In an open SDN-enabled environment this process is even simpler and will soon become regular practice.
Leaves the important case of wavelength management and troubleshooting. A decade ago it required external measurement equipment and quite some combinatorial skills for identifying root causes, today it has become much simpler. Embedded Wavelength Health Management solutions like ECI’s LightPULSETM collect all of the information that is available in the intelligent network elements, analyzes the information, and provides an easy-to-interpret overview of the status of the network. Even the location of a fiber-break can be displayed, as well as historical information about signal-to-noise trends and much more. Combine this with some alarm correlation and all difficult areas are addressed sufficiently.
Deploying alien wavelengths is an easy and economical way to upgrade aging optical networks without the need for a complete overhaul. It reduces the workload of the service staff to the absolute minimum since amplifiers and ROADMs remain untouched and goes hand in hand with the trend to deploy open, best of breed solutions in all parts of a network.
To learn more about how LightPULSE can help you introduce and manage alien wavelengths, download the LightPULSE brochure.