It is unquestionable that the amount of data sent all over the world is rising dramatically and that the time available to double the capacity of our network throughput to carry this increasing traffic is getting shorter and shorter.
At the same time, we still need to use interfaces of less than 100 Gbps throughput.
From the article DWDM – what it is and why you need it you already know that the passband of amplifiers is limited and that you cannot add new channels endlessly. So, what can we do to use the optical spectrum more effectively and, at the same time, enable your clients to use low throughput interfaces?
To prepare your network most effectively for the increase in traffic and also for future expansion, you should consider the following aspects:
- The profitability of the solution – primarily, the rate of return on investment,
- The preference for compact size and low energy consumption – compact equipment reduces the costs of leasing space in server rooms and low power consumption will enable you to keep OPEX under control,
- The ease of management, scalability and maintenance – all have an impact on your ability to activate new services using existing technical staff and can have a positive impact on operation costs,
- Providing a wide range of services – the more universal the device can be, the more of your clients’ needs you can satisfy.
The Wavelength Division Multiplexing technique enables you to significantly increase the potential capacity of a single fibre. If you assign a dedicated wavelength to each of your services, no matter whether it is Fibre Channel, Ethernet, SDH or OTN transmission, and then you multiplex it, you can send a great number of data streams over the same fibre. The important thing is that different services require different optical spectra.
Today, the most commonly used DWDM solutions are based on 100 GHz or 50 GHz grids. The number of channels available in such systems has been specified by ITU-T Recommendations. Thus, what should be done so as “not to waste” an optical channel for single services, e.g. 10 Gbps?
Help comes in the form of muxponder technology which enables you to aggregate a great number of services in a single wavelength. Similar to the standardisation of DWDM networks, in this case you can also make use of ITU-T recommendation G.709.
This describes, among other things, the principles of mapping various services to OTN. This standardisation, also in the case of muxponder-type solution, may be of key importance as this approach enables you to cascade muxponders in order to use bandwidth more effectively.
The popularization of coherent technology (more on this subject in our article: Understanding coherent transmission) has led to the current situation in which single wavelengths in WDM systems frequently carry 100/200 Gbps and the role of muxponders is to help in this process. An effective muxponder should support the following protocols: 10/40/100 GbE, 8/16/32G Fibre Channel or OTU2/2e/3/4.
Such a solution will enable you to fill the 100/200 Gbps lambda. Another question is how to deal with the low speed services that remain in our networks and what to do with services such as FE/GE, 1/2/4G Fibre Channel or STM-1/4/16? An optimal solution seems to be the cascading of muxponders.
Lower speed services can be aggregated to an OTU2 signal on one muxponder and the entire OTU2 stream can then be a component of the signals aggregated by a higher rank muxponder. This approach is possible due to standardisation. Moreover, it enables not only an optimal use of the optical spectrum, but also the clients’ ports available on their devices.
The growing demand for large amounts of data to be sent over optical networks makes it a constantly evolving challenge to optimize the use of the available resources.
On one hand we should maximize the use of the network, and on the other, we must consider the costs of running it.
Salumanus is a helping hand for companies whose functioning and effectiveness depend on efficiently working networks.