Satellite vs terrestrial?

Why is this the wrong question?


Johannesburg, 11 Mar 2019

As humans, we want to compare. It is in our nature. Perhaps it is left over from the grading system in our schooling years; perhaps it is because we understand better when we have a reference or a guide to compare against. Yet, as much as comparisons aid in understanding, they can also be very misleading if the context and reference is not well defined.

Look at how helpful it would be to compare flying to Cape Town versus taking the train. Both are transport mediums, so it sounds like a good idea to do a proper comparison before we make a transport buying decision. Yet, somehow, we know this is not so logical.

Let's talk satellite, fibre, 3G, ADSL, microwave, and wireless. These are all solutions for communication networks, and each option has some specific advantages and disadvantages. In our view, these are alternative technologies, not necessarily competing options. Apart from being communication technologies, these options have very little in common and actually have very diverse and fundamental physics and architecture differences.

Why satellite vs fibre is the wrong question

At its very core, satellite is a broadcast point-to-multipoint architecture. Fibre is a point-to-point network architecture. If it is a broadcast solution that is required, why would you consider a point-to-point network and vice versa? There might be other short-term requirements like time-to-market, or landlord access rights that can influence deployment choices to favour satellite as an interim service.

The principle architecture difference of point-to-multipoint versus point-to-point is also reflected in the commercial models available. Whereas satellite can enable pay-per-use or pay-per-site options, fibre is very much a pay-per-circuit model. When the user requirement is for long-term high-capacity demand at a fixed location, and fibre is the ideal point-to-point option, then that is the logical choice.

However, if you need to service multiple user locations, and some locations might not be suited for long-term investments or even have very fluctuating capacity demands, then rather use satellite, which, by nature, is more flexible and much more tactical than fibre.

Changing perceptions, one innovation at a time

The perception is that satellite is slow, expensive and the latency is a problem.

That was almost true back in 1960, when satellite was invented. With the latest satellite technologies enabling +50Mbps links to customer sites, and cost points dropping, it is a completely new landscape. Our advice is that perceptions and past experiences should best be evaluated under new technology scenarios to get an objective and updated view.

The innovation of new high-throughput satellites linked to satellite modem enhancements plus traffic optimisation solutions have moved the goalposts. For example, the high-capacity, deliver anywhere, nature of satellite can enable very effective business continuity services between multiple regional head offices. Linked to "pay-per-use" commercial models, this then becomes a very effective option for regional fibre networks.

It is not 'or', it is 'when'

We propose the discussion changes from: "Do I use satellite or fibre?" to: "When do I use satellite and when do I use fibre?" These are very different communication technologies, and they are alternative options, not competing options.

In summary, fibre is the long-term, point-to-point, fixed location and fixed cost option. Satellite is the tactical, anywhere, anytime, flexible, point-to-multipoint option. Understanding the principles, and considering the use case along these criteria, will map into feasible and sustainable solutions.

Share

Editorial contacts

Kim Gruttke
Q-KON Africa
kgruttke@qkon.com