Month: December 2014

Whenever I make a hotel reservation these days I can't help but wondering how good their Wi-Fi actually is or if it works at all. Most of the time I don't care because I can use my mobile data allowance anywhere in Europe these days. Outside of Europe, however, it's a different story as it's more expensive so I still do care. Recently I came across HotelWifiTest, a website that focuses on data rates of hotel Wi-Fis based on hotel guests using the site's speed tester. Sounds like an interesting concept and it's promised good speeds for the next hotel I'm going to visit. So let's see…

With LTE-Advanced Carrier Aggregation being deployed in 2014 it recently struck me that there's a big difference in deployed capacity between LTE and UMTS now. Most network operators have had two 5 MHz carriers deployed for quite a number of years now in busy areas. In some countries, some carriers have more spectrum and have thus deployed three 5 MHz carriers. I'd say that's rather the exception, though. On the LTE side, carriers with enough spectrum have deployed two 20 MHz carriers in busy areas and can easily extend that with additional spectrum in their possession as required. That's also a bit of an exception and I estimate that most carriers have deployed between 10 and 30 MHz today. In other words it's 15 MHz UMTS compared to 40 MHz LTE. Quite a difference and the gap is widening.

To secure my fixed and mobile data transfers I've been using OpenVPN for many years know. With fixed and mobile networks becoming faster I have to continuously improve my setup as well to make maximum use of the available speed at the access. At the moment, my limit at the server side is 30 Mbit/s while at the access side, my Wi-Fi to VPN Gateway's limit is 10 Mbit/s. Time to change that.

A quick recap of what happened so far: Earlier this year I moved from an OpenVPN server on an OpenWRT Wi-Fi Router to an OpenVPN Server running on a Raspberry. At the time my VDSL uplink of 5 Mbit/s was the limit. With that limit removed the next limit was the processing capacity of the RaspberryPi which limited the tunnel to 10 Mbit/s. The logical next step was to move to a BananaPi who's limit with OpenVPN is around 30 Mbit/s.

In many cases I was still limited to 10 Mbit/s, however, as I was using a Raspberry Pi as a Wi-Fi / VPN Client Gateway to tunnel the data traffic of many Wi-Fi devices through a single tunnel. For details see this blog entry and the Wiki and Code for this project on Github. To move beyond the 10 Mbit/s, I had to upgrade the hardware on this side to a BananaPi as well. The process is almost straight forward because I run Lubuntu 14.04 on the BananaPi which, like Raspian running on the BananaPi, is based on Debian Wheezy. With a few adaptations the script I put together for the RasbperryPi also runs on the BananaPi and converts it to an OpenVPN client gateway in a couple of minutes.

While I expected to see a throughput of 30 Mbit/s, the link between the two BananaPi levels out at 'only' around 20 Mbit/s as shown in the screenshot on the left. I haven't yet found out why this is the case as on both devices, processor load is around 65%, so there are ample reserves left to go faster. For the moment I ran out of ideas what it could be. However, doubling the speed with this step is not too bad either.

Just a quick post today because I struck me today what a wide difference in size there is today between network operators. On the high end of the scale there are network operator organizations that serve countries with a population of over a billion, i.e. 1000 million people and have a significant market share. And on the other end of the spectrum there are countries, yes, independent countries, with just half a million inhabitants in Europe, i.e. countries that are much smaller than even only a single mid-sized city in bigger countries.

In other words, even if one of the network operators in such a country is dominant, it doesn't have more than a view hundred thousand subscribers. Between 1000 million and less than a million are 3 orders of magnitude! Breathtaking that the way mobile networks are built and operated works on both ends of the spectrum and that there doesn't necessarily seem to be a sweet spot at some point in between for an ideal network and organization size.