Currently our network services use technology provided by Ciena and Juniper. Institutions are connecting their equipment to Ciena Ethernet Service Switches, and internet traffic is being handled by Juniper routers. These switches and routers are located in our data centres and on the premises at institutions. To send customer traffic, we use Ciena’s Common Photonic Layer (CPL) as a transport system. This is a DWDM (Dense Wavelength Division Multiplexed) system, which is able to transport 88 colours of light down a single optical fibre. About a year ago Ciena announced it was discontinuing sales of this system, which means that maintenance and support by Ciena will also be phased out. It is time for a new optical layer within the SURFnet network. We will soon be starting on the implementation of this new optical layer. What opportunities does it offer?
Innovation within the optical layer
The technology surrounding optical transport networks has not stood still over recent years. That is why 2017 is a good time to replace our optical system. In practice this means a tender. In issuing this tender, which took place in 2016, knowledge was applied from the Request For Information (RFI) of 2015, the WDM Conference in Nice, the European Conference on Optical Connections, as well as knowledge obtained from experiments and tests.
At the end of 2016 we concluded a contract with ECI Telecom, the winner of this tender process. This contract enables us to manage a transport network for up to 10 years, which will not only serve as data transport for the service layer, but which can also be used to develop optical services. Examples of optical services include alien wave transport services and supplying accurate time and frequency information. Alien wave transport services are ultra-transparent transport services in which the customer supplies DWDM coloured light and thus takes charge of a large part of the required transport technologies.
Over recent years, optical transport architectures have been able to make the transport within the network increasingly more flexible. At the start of the CPL era, waves were still being statically coupled and decoupled and forwarded via a fixed route through the fibre optic infrastructure. Now, at the end of the CPL era, light is still statically coupled and decoupled but is routed flexibly through the network. The static element comes from the fact that each one of the 88 different colours has its own, coloured coupling and decoupling port and that in turn has one per direction in which the light leaves or comes into a location. Imagine if when you left home on your red bike, you always had to start by turning right and when on your blue bike had to start by turning left. If you actually wanted to go the other way, then you would either have to change bikes or cycle as far as the first junction and then adjust your route, at which point you would still not be allowed to do a 180 degree turn.
SURFnet8: new situation
The SURFnet8 optical layer removes this restriction. It no longer matters what the colour of the light (colour of your bike) is and in which direction the light is coupled (left or right). All input and output ports are able to send light of any wavelength in any direction. In the case of a fibre optic fault or scheduled maintenance this means it is possible to recover or divert bandwidth, which the service layer can take advantage of, meaning that users will notice little or no deterioration in their service experience.
A future-proof transport layer
We expect that as a successor to Ciena’s CPL platform, ECI’s Apollo will also be around for a good 10 years. During this period it will be easier for SURFnet to offer connections above 10 Gbit/s even in the outer edges of the network. In this way, the network will grow organically in a way that will improve the robustness and availability of the network in more and more locations. Because now more and more institutions and users are locating their data in data centres, the periphery is becoming increasingly important.
The first step, however, is to replace the Ciena CPL platform by ECI’s Apollo platform. For this purpose, a design of the new SURFnet8 optical transport layer has recently been created and a provisional Bill of Materials (BoM) has been drawn up, which ECI will be using to make and configure its Apollo systems over the coming year. These systems will then be deployed to meet the current transport functionality and to provide bandwidth for the SURFnet8 service layer, for which the tender will be completed this year.
- Read more about the implementation of the optical layer at https://www.surf.nl/en/surfnet8
- For more information, contact Rob Smets at firstname.lastname@example.org