With over 12 submarine fiber optic cables and more than 30Tbps of network design capacity at the submarine landing points in sub-Saharan Africa, a debate is raging on as to whether communication satellite systems will continue to relevant in ICTs in Africa.

A couple of years ago during a panel discussion at the Africacom event in Cape Town, I got squawked for suggesting that satellite was a “stop gap measure” until fiber was rolled out throughout Africa. I did not mean to downplay the role of satellite systems in ICTs in Africa.

The truth of the matter is that even developed countries, such as the United States, still utilize communication satellites in areas that cannot be reached by fiber optic cable. It is safe to assume that communication satellites will continue to play a role in connectivity and other communication needs of Africans.

With innovative new satellite technologies coming into play we should expect that, while fiber optics will play a significantly more dominant role than before, satellite systems will continue to play a role in Africa.

The satellite vs optical fiber debate

Why bother spend a fortune on fiber optic infrastructure when communication satellites are already available?

The number one and most important rationale for operators to deploy fiber optics in their networks is the need for higher transmission rates. There is just not enough capacity on satellite systems to transport all the traffic generated by the ever insatiable bandwidth demand and the expanding mobile and wire-line access networks.

Providing broadband Internet connectivity to hundreds of millions of Africans will require backbone transmission networks with hundreds of Gbps of capacity. Each time mobile operators increase their broadband offerings to higher data rates, say from 2G to 3G to 4G or deploy wire-line broadband services such as xDSL or fiber, it pushes the capacity requirements on transmission backbone networks. This is why International telecommunication standards organizations have long since ratified a standard that enable the transmission of 100Gbps in a single fiber optic channel and are now working on 400Gbps and 1Tbps.

Such high levels of transmission capacity would require a very large satellite fleet. According to data tracked by the Union of Concerned Scientists, there are approximately 500 commercial communication satellites currently in use in the world ranging in throughput from 1Gbps for conventional Ku-band to 10Gbps for Ka-band systems. All the capacity in the entire global commercial communication satellite fleet can be transmitted in a single pair of optical fiber.

Limited capacity on satellite systems implies higher cost/bit compared to fiber. While there is a strong narrative in Africa of fiber being too expensive to roll out, the very low cost/bit of fiber over its long life time makes it more attractive over satellite for high capacity transmission.

Latency is a major disadvantage of geosynchronous satellite systems that orbit at 35,786 km above the earth. Latency for these satellite systems range from 540ms to 800ms and is problematic for data download, voice over Internet (VoIP) transmission, gaming and online trading. See my article, Latency: From Washington D.C to Kinshasa and Back in 567ms.

The main advantage of satellite systems over fiber is coverage, as they can be configured to cover any part of the world where fiber may not be deployable. Today, satellite communications can deliver voice, video, and data that can be accessed anywhere in the world.

Next Generation Satellite systems:

With more capacity available to offer higher speeds at significantly lower costs, next generation satellite systems will play a more pivotal role in provisioning of high speed Internet connectivity to Africa where fiber cannot be deployed.

The proposed O3B system has the potential of playing a more significant role in ICTs than conventional geosynchronous satellite systems.

O3B Networks is a satellite service provider developing a new global Internet backbone for telecommunication operators, Internet service providers (ISPs), and enterprise and government customers in emerging markets. The O3B Network system is going to target billions of consumers and businesses across 177 countries with lower-cost, high-speed Internet connectivity.

Because the O3B Networks satellite system will orbit in the Medium Earth Orbit (MEO) between 10, 000 and 15, 000km from the earth, the latency is significantly lower than that of geosynchronous satellites which comprise the majority of communication satellites today. O3B has a potential of offering services with significantly improved quality than geosynchronous satellite systems.

In conclusion, as more African countries gain access to submarine cables and all countries deploy fiber optic backbone networks, fiber will play a more significant role in providing International bandwidth and cross border connectivity. Satellite systems will maintain a niche market in mobile backhaul and access in remote areas. It will also provide redundancy where there are no alternative fiber optic paths.

For training on optical communications, visit FiberGuide's certified optical network associate (CONA) page.