“2020 is the 150th anniversary of the founding of the Eastern Telegraph Company, Sir John Pender’s cable network which would span the entire British Empire by the end of the century. At the end of the 1920s this group of cable companies merged with the Marconi wireless interests to form Cable & Wireless. The Telegraph Museum in Porthcurno, Pender’s first cable station and now a world-class museum, will be having various events in 2020 to celebrate their history.

The company’s first cable system was to connect Britain to India, and this image is the landing of the shore end at Aden, with Great Eastern out to sea.”

 – Bill Burns

igure 2 - Landing of the Eastern Telegraph Company’s Britain to India cable at Aden with the Great Eastern out to sea

Figure 2 – Landing of the Eastern Telegraph Company’s Britain to India cable at Aden with the Great Eastern out to sea

1.1.1 Historical Perspective

The first submarine cable in the world was laid in the English Channel in 1850 by the stream tug Goliath. It was a revolutionary event that communication beyond the ocean became possible, although the communication method was telegraph. In 1866, the first commercially successful transatlantic submarine cable was completed between Valentia, Ireland and Heart’s Content, Newfoundland, and submarine cable networks in the world were gradually expanded. (Ash, 2014)

Figure 3 - Cable Ship Goliath

Figure 3 – Cable Ship Goliath

In 1876, the telephone was invented, and communication was expanded dramatically, and in 1891, the world’s first submarine cable for telephone was built in the English Channel. In 1901, transatlantic radio communication was successfully demonstrated by Marconi, but it was not until 1923 that two transoceanic communication methods were realized – submarine cable communication and radio communication.

The first attempt at laying a transatlantic telegraph cable was promoted by Cyrus West Field, who persuaded British industrialists to fund and lay one in 1858. However, the technology of the day was not capable of supporting the project; it was plagued with problems from the outset and was in operation for only a month. Subsequent attempts in 1865 and 1866 with the world’s largest steamship, the SS Great Eastern, used a more advanced technology and produced the first successful transatlantic cable.

The first transpacific submarine telegraph cable was completed in 1902. It ran between Australia, New Zealand, and Canada via Norfolk Island, Fiji and Fanning Island. In 1906, the submarine cable between Tokyo and Guam was opened to traffic, and telegraph service with US was inaugurated. However, after that, telegraph and telephone traffic using radio communication increased because of the installation and operating costs.

The first transoceanic coaxial submarine cable, including repeaters, was TAT-1 laid across the Atlantic Ocean, and went into service in 1956. In 1963, the first transpacific coaxial cable (COMPAC) connecting Australia and New Zealand with Canada via Fiji went into service. It was followed in 1964, by TPC-1 which connected the US with Japan via Guam and Hawaii. In 1967, INTELSAT-II was launched over the Atlantic Ocean, and satellite communication was inaugurated.

1.1.2 The Optical Age

In the 1980s, optical submarine cable systems were developed. The first transoceanic fiber optic system was the transatlantic, TAT-8, which was ready for service in 1988. Telecommunications with high quality and high capacity became possible, and optical submarine cable networks were extended all over the world. The first generation of optical systems regenerated the optical signal within the submerged repeaters. In the mid-90s regenerators were replaced by optical amplifiers, which allowed the simultaneous transmission of more than one wavelength. Currently, the main method for international telecommunications is the use of submarine cables; 99 percent of international telecommunications is carried over submarine cables.

Antarctica remains the only continent yet to be reached by submarine telecoms cable. In 2017, the Arctic received its first significant submarine cable system. Future such systems, both regional and transoceanic, are in the planning stages. The goal of a northwest or northeast Arctic passage seems within reach.

In recent years, many submarine cable projects have been progressing in the world. Communication infrastructure with higher speed and larger capacity is required to support the rapid growth of the Internet and, video transmission, and so demand for new submarine cables is increasing. This trend is expected to continue for the foreseeable future.

1.1.3 History of Oil & Gas Submarine Cables

In the late 1970s, Offshore Telephone deployed a coaxial Oil & Gas cable system followed by in the mid-1990s PetroCom’s FiberWeb inter-platform fiber cable system. Both systems were in the Gulf of Mexico and both systems failed and were eventually abandoned. (Berlocher, 2009)

The first successful Oil & Gas submarine fiber cable was installed in the early 1990s in the North Sea for BP. In 1998, PetroBras developed an offshore platform system in the Campos Basin and in 2001, BP developed the Central North Sea Fiber Optic Cable, a submarine cable that linked the Scottish mainland with offshore platforms. In 2002, Saudi Aramco developed the Offshore Fiber Optic Cable System and in 2008, BP developed the BP GoM cable system, the latter of which becoming the model for future such systems. Since 2001, the total length of all fiber cable in use for Oil & Gas cable systems has increased by over 550 per cent. (Nielsen, 2012)

As the industry focuses on utilizing new technologies to increase efficiency and automation as a key strategy to reduce cost and maintain margins, it is expected to drive up the demand for new offshore fiber systems. Worker tracking and safety, remote monitoring, improved seismic mapping, big data analytics and more all require higher bandwidth and lower latency than traditional satellite and O3b connections can provide. The push for efficiency to reduce costs and increase production help to offset weaker oil price when times are tough and maximize revenue when prices are high. As these techniques and processes become more widespread, new submarine fiber optic systems will be required.

1.1.4 The Modern Era

Since the 1990s, the submarine fiber market has been characterized by rapid development in optical technology which has improved both network efficiency and system design capacity. Over the last 30 years, the industry has gone from measuring capacity in Megabits in the early 90s to systems with hundreds of Terabits in 2019. One of the biggest contributions to this capacity increase was the development of Wavelength-Division Multiplexing (WDM) – first introduced on the SEA-ME-WE 3 system in 1999.

This technique allows cable systems to send multiple optical wavelengths over a single fiber pair, reducing the amount of fiber needed and eventually bringing down the cost of new cable systems. The introduction of Dense Wavelength-Division Multiplexing (DWDM) allowed many more wavelengths – or channels – to be added on a single fiber pair which further accelerated the increase in design capacity on a single cable.

Wavelength capacity has increased at a rapid pace since the early 2000s with 10 Gbps first entering the market around 2003 and 100 Gbps wavelengths appearing as early as 2010. This tenfold increase in wavelength capacity in the span of less than a decade is another major contributing factor to the rapid increase in available global bandwidth over the last 20 years.

Alongside the increase in channel capacity, the concept of system upgrades was developed. In the early to mid-2000s, it became possible for system owners to swap out components in the Submarine Line Terminal Equipment (SLTE) to increase capacity instead of the need to build an entirely new cable system. Systems upgrades have since become the most cost-effective way to add capacity along a submarine cable route and can be actioned in a much shorter time frame than developing a new system.

Looking ahead, advancements in Artificial Intelligence (AI) managed systems will increase the capability and efficiency of networks as they become increasingly more complex.