Subsea Cables & Internet Infrastructure

The FEC (forward error correction) encoder takes the bit stream and modifies it so the FEC decoder can detect and correct bit errors due to optical or electronic noise. To accomplish this, FEC adds extra redundant bits to the overhead that the decoder can use to identify and fix bit errors. The redundant bits are a mathematical function of the data payload values. This scheme enables transmission to keep bit errors very low without payload retransmission. It is similar in philosophy to the checksum field in IPV4. The difference is that the IPV4 field is strictly limited to detecting overhead errors and the routers respond to checksum failure by dropping the packet and forcing retransmission. In contrast, FEC is designed to detect and fix payload errors without retransmission.  The next interesting step is the bit to symbol conversion. Coherent optics represents bit patterns using combinations of optical properties like phase, amplitude, and the two polarization modes. So the bit pa...

There is strong demand for wavelengths connecting Europe's key routes like London/Paris, Amsterdam/London, Amsterdam/Frankfurt, Frankfurt/Paris, Paris/Marseille, Zurich/Frankfurt, Milano/Marseille, Madrid/Paris, Madrid/Lisbon, etc. Much of this involves African ISPs that come to Europe to peer and buy transit as well as Indian and Asian firms.  But Europe is different. A 100G wavelength varies from the mid to upper 800 Euros per month to the mid 1500 Euros depending on term, route, physical diversity, latency, etc. Because rates are low focusing on price is a mistake. Don't be transactional like a certain American President. You will save little because prices are already low, but sacrifice a lot in terms of latency, time waiting for price quotes, delivery, uptime, routing options and commercial flexibility. For example, my favorite provider has fast routes for general bandwidth users that are usually 1 to 4 milliseconds lower latency than the rest of the pack. So you can save ...