Author: Martin

When it comes to cellular networks, Austria is one of the most advanced countries concerning network ubiquity, speed and low prices. To see how things evolve, a German mobile communication magazine together with a test house does an anual in-depth test of networks in Germany, Austria and Switzerland. Their reports of these activities are usually quite insightful. Here's a link to the ENGLISH version of the 2012 report for Austria. An interesting read that shows what's possible, even in a country where for around 20 euros a month there's so many voice minutes included and so much data that it's hard to hit the limit (read: usage is high).

The Internet is great for freedom of choice, freedom of use, freedom of expression, freedom of speech. I really like that I'm able to post things on my blog that can be read anywhere in the world where the open Internet is available. I equally like that there are search engines that let me find documents and information no matter where they are stored and I like small companies that are offering videos, podcasts and other content on niche topics that would never make it to the mainstream media.

So all of these things are great and do not match the title of this post at all. However, the Internet is now more and more also used to restrict the freedom we used to have. Here are some examples: Companies such as Apple, Google, Microsoft and Amazon have great products that are used and enjoyed by people around the world including the author of this post. But more and more these companies are trying to build silos by offering software and hardware that is tightly controlled by them. Third parties offering services and content independently are unwanted. A few examples: Apps can only be downloaded to the iPhone from the Apple store, Amazon's kindle only accept apps from Amazon's store and also Microsoft wants to go down that road with Windows 8, as metro apps can only be installed from Microsoft's web store.

Why such limitations and why now? The second part is answered easily, it's because it's possible to do it now. 10 years ago, restricting devices to a particular web store was not feasible as many PCs were not yet connected to the Internet and hence, installation of new programs from disks and CDs was the norm rather than the exception. Nobody would have accepted to only be able to install programs that had a Microsoft certificate. This has significantly changed as most devices are now connected to the Internet and the ease of use of exclusive web stores make many people blind to the fact that they are giving up a freedom they used to have. Giving up this freedom means that those who do are subjecting themselves to the values that a company thinks are the right ones rather than your own.

The first question of why this limit is imposed is often answered by saying that this protects users from badly designed or even malicious programs and that it's in the user's own good. To a certain extent that is of course true as programs go through a centralized audit. But I am a grown up and responsible person and I want to decide for my own. Someone else deciding what is good for me or not, no, thanks, I like my freedom. Google is using a somewhat different approach for Android. By default, downloading and installing apps from third party sources, e.g. from this web site or via sideloading from an SD card is blocked. However, the user is informed that if he really wishes to do that, it can be enabled in the settings. From my point of view that is a fair middle ground. It protects users from accidental installs of malware but still allows to open the door to freedom for those who want it. Also it is an incentive for users to buy software and content from the company that built the device or the operating system which is, by the way, the main reason for companies going down that road. Company interets and freedom do not have to be at odds with each other if done the right way.

One should also keep in mind that malicious programs are not the only way for a device to get infected by malware. Zero day exploits in web browsers that can inject malicous code that downloads keyloggers, scareware and other nasty programs are still frequently found. Web browser plugins such as Flash and Java leave the barn door wide open as well. Also, documents in email attachments that exploit weaknesses in office programs and files looking like documents but being executables are also able to infect systems and are very common today. A centralized and exclusive app store does not help against any of that. So the security argument might even backfire as it creates a false sense of safety.

Unfortunately, the anti-freedom effect the Internet has these days doesn't stop here. More and more, ubiquitous Internet access is also used for location and usage tracking, and only media pressure has so far prevented some excessive forms from becoming the norm. Anyone remember the "Carrier IQ" row from only last year? Yes, people forget quickly… Oblivion is the enemy of freedom.

Let also think about cloud services, freedom and privacy for a moment. Have a look at the terms and conditions of your favorite cloud service company. Is the data you store there, be it emails, documents, pictures, etc. really still yours or have you, by uploading them to that cloud service given the owner of the cloud service usage and redistribution rights to your data? You don't know? Well better check it out and ask yourself if this is acceptable to you or not. Note that I am not saying that all cloud services are bad. I use cloud storage for example but only with encrypted containers and the key is under my control and never ends up in the cloud. I also use email, obviously, one of the first cloud services and I am quite aware that I have no control over who sees what on the way from me to the recipient. And I act accordingly.

No, not everything is bad and if one is aware of these things one can act accordingly. My desktop is free, I am using a Linux distribution and I can install whatever software I like. Yes, it's not the only choice for a free desktop today, but companies are working hard to make it the only choice in the future. I use a VPN solution to protect my Internet connectivity when I travel and to prevent unwanted interference with the data I exchange such as unwanted network side compression or VoIP blocking. On the mobile side I use an operating system that lets me install any third party software I want and I only use cloud services to store unencrypted data I don't consider private, personal or my own. All of that takes effort, another enemy of freedom.

Freedom is not given it has to be struggled for.

For years, I've been collecting information from all around the web about which mobile network operator has how much bandwidth in which bands. Such information is quite helpful when it comes to understanding strategies and arguments in debates. No need to do that anymore as CEPT has just released a very comprehensive document giving an overview of spectrum owners for all European countries for the 800 MHz digital dividend band, the 900 MHz GSM/UMTS band, the 1800 MHz GSM/LTE band, the 2100 MHz UMTS band and the 2600 MHz LTE band. Here's the link to the page and here a link directly to the document ('ECO Report 03'), enjoy!

I recently noticed how relative time can be. Take 5 minutes for example, is that a long or a short time? I'd say it depends. Here are three examples

• Waiting 5 minutes in a call center queue seems like ages.
• Waiting for 5 minutes for a file download to finish because the server is on the other side of the world and has a slow link feels sluggish at best. 

• But: Waiting for 5 minutes in a doctor's waiting room before it's your turn feels very short.

Now how do the extra 6 seconds required to establish a voice call between two LTE mobiles due to Circuit-switched Fallback (CSFB) feel?

With mobile network operators using more and more radio systems (GSM, UMTS and LTE) simultaneous and on many different frequency bands, it's getting a bit difficult with traditional network coverage maps to find out where what kind of mobile device can be used. Some network operators have therefore now begun to diversify their maps with options to show different technologies and different frequency bands different colors.

Two interesting examples:

Elisa from Finland shows GSM, UMTS 900 and UMTS 2100 and LTE (1800???) coverage and dual carrier operation in separate colors

T-Mobile Germany that shows GSM, UMTS, LTE 800 and LTE 1800 in different colors (especially for devices that are not LTE 800 capable…)

In both cases, GSM coverage is still wider than the combined UMTS and LTE coverage. Such maps are also interesting to deduct what kind of network strategy the operator follows.

Quadrature Amplitude Modulation, or QAM for short, is a modulation technique used by systems such as UMTS, LTE and also by microwave backhaul systems. UMTS and LTE use QAM, 16QAM and 64QAM to encode 2, 4 or 6 bits per transmission step. And 64QAM already pushes the limits quite hard and is only used when a user is very close to the base station.

The highest modulation technique I have heard about for microwave Ethernet backhaul systems to transfer data back and forth from and to the cellular base stations so far is 256QAM, i.e. 8 bits per transmission step. This is possible due to the very directional focus of the radio beam versus sectorized transmission in cellular systems.

Now Dragonwave is saying that their latest system is capable of 2048QAM, i.e. 11 bits per transmission step. Further numbers cited in the article match that claim. A peak throughput of 550 Mbit/s over the channel mentioned in the article would mean that a 50 MHz channel is used for data transmission. Quite a fat pipe but not unheard of for microwave backhaul (see also link above).

An incredible number from today's perspective despite the directional nature of the transmission and pushes the state of the art quite a bit.

P.S. The latest version of Wi-Fi, 802.11ac uses 256QAM for very good signal conditions.

I've come to like tablets for purposes such as eBook reading or the occasional web search or Youtube video on the couch. However, I can't imagine just taking a pad with me instead of a small notebook computer when I travel, it's just too restrictive in terms of multitasking especially when it comes to creative tasks from email to word processing. But I think we are getting closer with Canonical just having announced that they've created an easy installer to get the current Ubuntu version running on a Google Nexus 7 tablet.

It's just experimental at this point but if there is enough processing power in that ARM based CPU then it will hopefully mature quite quickly. With one gigabyte of RAM it is on par with my 3 year old first generation Intel Atom based netbook that I've used intensively as my private PC when traveling during that time.

And who knows, perhaps in a year from now together with a thin or foldable Bluetooth keyboard for productivity, a pad running a decent Ubuntu version might finally be an alternative for a notebook. Kudos to all working on this!

When mobile networks are discussed, it's usually about the air interface, i.e. the last few meters between the base station antenna and people's mobile devices. What gets little attention in the press, however, is how the data is transported between the base stations, the radio network controlers (in case of UMTS) and the core network. This is what's called the 'backhaul' network. On a very high level it's clear that UMTS and LTE networks today due to their broadband transmission speeds can no longer use 2 MBit/s E-1 connections but have to use something else. In practice that something else is either Fiber, copper cable or microwave. But which technologies are actually used over that medium in different parts of the backhaul network? This is what 'Mobile Backhaul' by Juha Salmelin and Esa Metsala gives an in-depth answer to. While reading the book I've learned a lot about how pervasive Ethernet technologies have become in recent years over any kind of medium. I've gained a much better understanding of how Ethernet protocol extensions for use in the WAN work and how MPLS plays into the game. In short, a very recommended read!

When you perform a manual network search in the UK today, you'll see 5 networks on the display. They are in no particular order:

• O2
• Vodafone
• T-Mobile
• Three
• Orange

But in fact with the recent decision of the UK regulator to allow network sharing between Vodafone and O2, there are a mere two mobile networks left in the UK. And non of the above mentioned 5 companies are actually operate one of those networks anymore. And here's why:

T-Mobile and Orange have merged and are soon going to be re-branded Everything Everywhere (EE) for consumers as well. From what's in the press they have already begun to put their network together, which reduces the number of companies to 4.

And then there's the UMTS network sharing deal between EE (form the T-Mobile side) and Three UK in a common company called MBNL (Mobile Broadband Network Limited). On their web page they write:

"Having successfully delivered the consolidation project, MBNL is now responsible for managing the consolidated network of sites including the 2G and consolidated 3G radio access networks for Three UK and Everything Everywhere. We are also responsible for the delivery of all site upgrades to continuously improve the consolidated network."

So we are down to three, i.e. MBNL, Vodafone and O2. But now Vodafone and O2 have been allowed to share their network as well, perhaps to 'compensate' the two companies for EE's early LTE start in the 1800 MHz band? As part of the network sharing agreement, Vodafone and O2 will establish a new network operator called "Cornerstone" that will manage and operate their consolidated network.

In other words, in the future there will only be two networks left in the UK:

• MBNL
• Cornerstone

I really wonder how under such circumstances competition will continue to flourish!?

In effect, Vodafone will be unable to differentiate from O2 and EE has no real means to differentiate from Three. They all claim that using their own spectrum will keep competition alive but I strongly doubt that. After all, everything is shared, from the antennas, to the base station to the backhaul. Only core networks will remain in the hands of the 4 'hollow operators'. So what for example if one gets a capacity issue in some locations? If the company had its own base station it could simply add a carrier. But that won't work so easily now because the base station and backhaul is shared. Is there enough capacity and room left for another carrier? Also, putting another base station into place close by will be difficult as the partner that shares the network might not want to do that. Perhaps putting micro base stations somewhere under direct control of the parent? Again difficult because neighbor cell relationships and handovers need to be coordinated. No, probably not possible with a shared network either. And even without that the bill is likely to come later when 'real' network operator asks for more money after the contract expires.

So it's down to two networks in the UK and it's going to be difficult to impossible to revert that trend if things don't work out for the consumer. A hazardous and unnecessary experiment…

Recently I read that one of the 4 big network operators in the US supposedly has 37.000 base stations in the country. Sounds like a lot, doesn't it?

Well perhaps, but only until you compare it to other places in the world. Take Vodafone Germany for example. Back in 2009 they said that they have 20.000 GSM base stations, so about half of that number above. But, it's for a population of 82 million compared to almost 314 million in the US and a landmass that is significantly smaller than the US. From that point of view 37.000 base stations is not very much and explains a lot…