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Netflix experience on Ka-Band VSAT in Kenya

January 8, 2016 7 comments

Yesterday I, like most people here; woke up to the news that the American multinational provider of on-demand Internet streaming media; Netflix, has expanded into several countries including Kenya. Social media reaction in my view was a tie between those who think these new comers will ‘disrupt’ the market currently dominated by Multichoice’s DStv. The jury on what exactly is the meaning of disruption as applied in that discussion, is however still out.

My views on their foray into Kenya aside, I decided to test the service on my home VSAT link. This was after I read on how it works just in case I had made any assumptions that were wrong. Here, I found out that the minimum recommended bandwidth is 3 Mbps for SD quality video and 5 Mbps for HD quality video.

The particulars of the link are as follows:

  • Ka-band service off the Avanti Hylas-2 satellite at 31 degrees East (somewhere above Uganda)
  • 74 centimeter elliptical dish with a 1 watt Ka-band radio
  • Hughes HN9260 satellite router
  • 15 Mbps download and 2 Mbps upload speed
  • Netgear AC2350 Nighthawk X4 WiFi router

With the VSAT kit I achieved a strong enough signal to enable a DVB-S2 carrier at 8-PSK 8/9 on the down link and do a TDMA/FDMA carrier of 2048 Ksps at QPSK 4/5 on return w.r.t the remote terminal

The 74 centimeter dish with a clear view of the western sky. From Nairobi the look angle is a favourable 88.5 degrees

The 74 centimeter dish mounted on a perimeter wall  with a clear view of the western sky. From Nairobi the look angle is a favourable 88.5 degrees

I registered an account and selected a 58 minute SD quality documentary titled “Rise of the drones” and proceeded to view it. Its took about 3 seconds to open the stream and the streaming started.

The Netflix main screen opened on the Firefox browser

The Netflix main screen opened on the Firefox browser

The picture quality was as expected for  an SD video on my old laptop, I however could not identify how to check this video’s resolution on the stream.

Video quality was consistent throughout the session with no downward review of picture quality

I watched it to the end without a single “Netflix and Chill as it buffers” moment and the stream download rate indicator was about 5 minutes ahead of the play indicator throughout the time.

rate

The progress bar (in lighter shade of grey ahead of the red play duration bar) showing about 5-minute lead

The VSAT links Cacti graph for the 58 minute session showed  that the stream consumed an average of just below 3 Mbps with a peak of 3.7 Mbps. During this time the total downloaded data was 1.3 GB by calculating the area under the graph.

Cacti graph utilization during the 57 minutes of documentary streaming.

Cacti graph utilization during the 58 minutes of documentary streaming.

The above results means that in a multi-viewer scenario where more than one person is using Netflix on the LAN , the VSAT’s 15 Mbps capacity can support 4 concurrent viewers without a problem and will be limited only by the WiFi routers’ capability.

Update: I did Netflix for the entire day on Saturday 9th (via a HDMI stream dongle on TV) with my kids in the usual TV schedule as we do on DSTv (punctuated with sessions of outside play, reading/study, quiet times and no TV during meals). We had consumed 19.4 GB by the time we went to sleep.

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Ka-band Satellite Broadband: Hit or Hype?

August 21, 2012 8 comments

60cm Ka-band dish on a roof top capable of delivering up to 15Mbps

With the landing of several undersea cables in Africa in the last three years, many a pundit have hailed it as a new dawn of telecommunications in the continent. The cables brought with them massive bandwidth capacities to the continent that enabled faster and cheaper communications. Before the arrival of these undersea cables, Satellite was used to connect Africa to the rest of the world. These satellites had the following characteristics:

  1. Expensive due to the fact that satellite transponder leasing was expensive due to the extremely high demand for the capacity. This demand reached peak circa 2005 when operators were even buying capacity from satellites that were still on paper, not yet built and launched.
  2. Due to the cost and scarcity of capacity, many back-haul pipes were congested making satellite communications slow and irritating to use.

The arrival of cheap and abundant terrestrial capacity led many to declare that satellite was destined to history books and that there will be no market for satellite broadband in the years to come.

Three years down the line, reality has hit home as the following facts downed:

  1. The issue of back-haul was resolved by the undersea cables, these cables did not however address the last mile access problem. There is a lot of capacity at the landing stations that cannot be distributed to end users as there is no good last mile infrastructure in place. Spectrum scarcity has also made things worse.
  2. Even on the existing last mile networks and those being put up to meet this demand, reliability has been a key issue due to poorly designed networks and fiber cuts. Industry leaders now seem to agree to this fact as seen here
  3. No regulatory framework was set-up to harness the advantages brought by the availability of bandwidth. Regulators failed to come up with new policies and laws such as infrastructure sharing, spectrum farming and sharing

The result is that the consumer has not benefited much as ISP’s and NSP’s continue to offer mediocre services. There are reports of some ISP customers getting as low as 92% availability which translates to about 29 days of outage in a year.

Will Satellite make a come back?

Before we answer this question, we need to be aware of the key advantages that satellites provide. These are:

  1. Very high availability. No technology beats satellite when it comes to availability. Downtime is rare and far in between making majority of well designed satellite systems achieve the proverbial 99.999% availability (52 minutes of outage in a year).
  2. Satellites offer instant availability of service over a large area without the need to lay additional infrastructure.

With the advent of Ka-band satellites, the landscape is about to change as these will bring with them large amounts of bandwidth and make them available instantly to large geographical regions. The key advantage of Ka-band satellites over the more traditional Ku-band and C-band satellites are:

  1. In terms of capacity, one Ka-band satellite is equal to about 100 Ku-band satellite yet they cost the same to manufacture and put into orbit. This means that capacity on Ka-band will be much cheaper to the point of giving fiber capacity competition.
  2. Ka-band utilizes spot beam technology that enables the use of smaller antenna (as small as 60cm) and cheaper modems. At the moment, a full Ka-band kit is competitive on price to terrestrial technology equipment. Intelsat is developing a spot beam architecture utilizing all bands that will allow 2 satellites to cover all populated continents of the world. Read more on the Intelsat Epic™ project here

With more capacity available to offer higher speeds at much lower costs, with equipment being cheaper and more competitive to terrestrial offerings and giving much higher reliability that terrestrial services can only dream of. What will prevent Satellite broadband from making a come back?

If recent events are anything to go by, Satellite broadband is already making a come back to Africa. The recent launch and uptake of capacity on Yahsat 1B and Hylas-2 satellites over Africa will  avail high-speed capacity whose quality rivals that of majority of the terrestrial services latency not withstanding. The main reason why i think Ka-band will be a game changer in the African broadband market is that operators have realized that it is one thing to roll out a terrestrial infrastructure and another to operate and maintain it. Operational costs of the newly laid terrestrial wired and wireless networks are becoming prohibitively high due to vandalism and sabotage. The terrestrial networks offer very many points of failure to offer any reliable service. Ka-band satellite will offer cheaper bandwidth that is more reliable and easy to access and install on any place in the continent. It takes an average of 3 weeks to survey and install a fiber cable in a city like Nairobi, it takes about 2 hours to fully set-up a Ka-band dish and connect to the Internet….. Once the fiber hype dies, Ka-band broadband via satellite will be a hit in Africa.

Anyone dismissing my argument should look at the following links that talk of roll-out and expansion of Ka-band satellite in Europe, Middle east and USA which we consider to be pretty “wire up” than Africa.

  1. Hughes announcement of the launch of Echostar 17 to offer 100Gbps broadband services in North America: http://bit.ly/ShARi6 after the successful launch and sale of capacity on Spaceway satellites
  2. Viasat Ka-band 100Gbps broadband service offering in North America: http://bit.ly/ShBAjj
  3. Avanti communications announcement of the launch of Hylas-2 to offer services in Mideast, Africa, Europe and the Caucus: http://bit.ly/ShBYhL

Africa Will Ignore Satellite Communications At Its Own Peril

May 25, 2012 7 comments

The landing of various undersea cables on the African shores in the last three or so years has heralded a new dawn of high speed communications that offered clearer international calls and faster broadband speeds. These cables have made bandwidth which was once a scarce commodity be in near oversupply. Indeed as I write this, quite a huge chunk of the undersea capacity is unlit.

With the arrival of these cables, telcos and ISPs that once depended on expensive FSS (Fixed Satellite Service) capacity moved their traffic to the more affordable undersea cables. Cost of bandwidth came down but not to the level envisioned by the consumers as most fell by about 40% and not the expected 90%. I had warned of the possibility of these prices not coming down by 90% as was the expectation and hype in a previous blog post in 2009.

Satellite At Inflection Point

Incidentally, when the cables were arriving, some major developments were happening in the Satellite world. However, due to the hype and excitement of the arrival of undersea cables, majority of us didn’t care or notice these changes that were set to revolutionize satellite communications. These changes have created a lot of excitement in the telecommunications world but are largely ignored here as we believe that the undersea cables are the future.

The Situation In Kenya (and by extension Africa)

With several cables landing on the Kenyan coast, it would be expected that quality of service from ISP’s would be at its best. However, this is not the case as the quality of service has greatly deteriorates over time due to a poorly maintained last mile network. We have bandwidth at the shorelines but we are unable to fully utilize its potential. Majority of the operators in Kenya embarked on ambitious plans to lay last mile fibre cable around the country, the same thing is happening in other African countries too albeit at a slower pace. these are good steps, however, these telcos have oversimplified the issue of last mile access to that of laying cable on poles or burying it underground. That’s just 5% of the entire job of last mile provision, the other 95% lays in maintaining the network which sadly none of the telcos were prepared for. they thought that after laying the cables, money would start flowing in. Last mile cable cuts due to civil works is currently one of the biggest cause of downtime in Kenya today, hardly a day ends without incidents of cable cuts as roads are being expanded, new buildings come up and natural calamities such as trees falling on overhead cables and flooding of cable man holes.

Collectively as Africa, we seem to underestimate the size of this continent, operators do not know what it will take to wire Africa to the same levels as Europe or the US. The map below shows the task ahead of us as far as wiring Africa is concerned, its not going to be an easy job. Africa is the size of the US, China, India, Europe and Japan put together. Click on it for a larger image

True size of Africa

This size poses a challenge as far as laying last mile networks in Africa is concerned, the lack of reliable electric power supply also poses a challenge on how far these networks can grow from the major cities. Click on this map here  to see how far behind Africa is in as far as power supply distribution is concerned, it was taken by NASA at night sequentially as each part of the earth moved into night time.

As seen above, it will take quite a large amount of investment to bring this continent to the levels of other continents as far as connectivity is concerned.Even when this is done, it will be an expensive affair which will make connectivity expensive as investors will need a return on their investment.

However, all is not lost as the once derided Satellite service is now making a comeback and will soon give terrestrial services a run for their money. Already, the US and Europe are undergoing a major shift in the use of Satellite to provide broadband service. Currently there are more investors putting their money into satellite launches than into laying undersea cables.

Below are some of the developments in Satellite that will herald this comeback but have sadly slipped past most of us.

Ka-Band Commercialization

Unlike Ku and C band satellites that were in use before the arrival of cables in Africa, Ka-band satellites use spot beam technology which allows frequency re-use and the provision of hotter beams. What this means is that satellite capacity can be greatly expanded due to frequency re-use and CPE equipment is now cheaper due to a hot beam/signal. A single Ka-band satellite is now equivalent to about 100 Ku-band satellites for the same cost. The two main reasons why satellite was ditched for fiber was the cost of equipment and bandwidth. Due to these two developments, satellite operators will soon be offer prices as low as 300 USD per Mbps down from about 6,000 USD per Mbps.

The reason why Ka-band was not commercially viable for sometime was because the technology had not mature enough for viable commercialization. Ka-band which operates at the 17-30Ghz range is susceptible to weather interference but there now exists techniques to counter this hence greatly improving reliability. The High operating frequency meant more expensive detecting equipment (modems) but advances in technology have allowed for the manufacture of affordable 200 USD modems today.

More Efficient modulation Schemes

In Communications, the amount of data that can be sent over a transmission channel is dependent on the noise on that channel and the modulation scheme used. There have been great advances in modulation techniques and noise suppression allowing the pushing of more data over smaller channels. This includes the use of Turbo coding which is so far mankind’s best shot at reaching the Shannon limit. One recent and notable development was by Newtec where they managed to push 310Mbps over a 36Mhz transponder which translates to 8.6Mbps/MHz , previously the much you could do was 2.4Mbps/MHz. Read the Newtec story here.

Combine this with Ka-spot beam frequency re-use and you will have satellite capacity that is cheaper than fiber bandwidth, if you add this to the reach that satellite foot print provides, you will have instant broadband available on the entire continent.

MEO Satellites

At around the same time the cables were landing, a Google-backed broadband project was being announced. The project dubbed O3B (Other 3 Billion) denotes the unconnected 3 Billion people in the world. Google believes that this is the most viable way to avail broadband to the masses. Otherwise how do you explain the fact that Google has never invested in fiber capacity to Africa or the developing countries? I wrote about the O3B project in a previous blog post that you can read here.

The O3B will utilize satellites that are closer to the earth hence the term MEO which stands for Medium Earth Orbit. The fact that these satellites are closer means that latency on the links will be much lower (at 200ms) compared to traditional satellite capacity that gives about (600ms). This will enable higher throughput at lower latencies. To read more on the relationship between  latency and throughput, read this tutorial here

Satellite Refueling

majority of the satellites in orbit have a lifespan of about 15 years. This lifespan is determined by the amount of fuel it can carry. This fuel lasts about 15 years and once its depleted, the satellite cannot be maneuvered and is therefore not usable. As a write this, Intelsat which is the worlds largest commercial satellite fleet operator, has signed up for satellite refueling services from MDA corp to extend the life of some satellites by about 5 years. What this means is that operators can get more money out of their satellites due to extended life and therefore they can now offer cheaper bandwidth.

Combine the advantages of Ka-band spot beam, efficient modulation, LEO satellites and ability to refuel satellites and you have with you the solution to the myriad of problems afflicting consumers in Africa today as far as reliable and high speed broadband connectivity is concerned.

By the end of 2014, Satellites will offer cheaper, reliable and more affordable bandwidth than undersea fiber optic cables. This is the reason why investors are flocking to launch satellites than lay cables. These include Yahsat which is an Abu Dhabi company, Avanti communications launching in Europe and Africa and Hughes which is launching Ka-band satellites in the US mainland for broadband connectivity.If undersea cables were as good as was touted by local operators, why are investors putting money in launching in the US and Europe which are more wired than Africa? Locally, the Nigeria government launched its own communication satellite that they say will enhance broadband reach in the country faster than terrestrial technologies.

Watch this space….