Monthly Archives: January 2015

Article, English

Whatsapp’s web interface

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Finally! The long awaited web interface for Whatapp is here! But wait a minute. It is not all that wonderful as you expected. The new web interface for Whastapp simply creates a bridge between a web browser and your phone which is ultimately sending your messages.

Image from enter.co.

 

The good thing is that Whatsapp can claim that the messages sent this way are secure.  This argument is fair enough, although it could have been avoided.

Let’s now start enumerating the bad things.

  • Only works with Google Chrome. Yes, the web interface only works if you use Chrome. Forget it if you want or prefer to use other browsers.
  • Only works with the app on Android, Windows Phone and Blackberry. Do you have another mobile OS? You cannot use this feature.
  • Your phone needs to be connected. If you paired your phone but you lost connection or your battery died, that’s it: no more Whatsapp for you. The D-tour that the messages have to do is just, sigh, idiotic.

Sure, it is better than nothing. Still not good enough to make it my preferred messaging application.

Article, Español

4G en Argentina

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En 2014, el gobierno argentino licitó las frecuencias para el uso de LTE, la cuarta generación de redes de telefonía celular. Lo que en el mundo se conoce también como 4G. En este artículo vamos a ver qué hay que tener en cuenta para prepararse para disfrutar de 4G en Argentina.

Bandas de frecuencia

Como es tendencia en todo el mundo, se abrieron nuevas bandas de frecuencias para la implementación de 4G. A las dos bandas usadas hoy en Argentina (conocidas como bandas de 850MHz y 1900MHz), se agregaron la bandas AWS y 700b. La banda AWS usa espectro en 1700MHz y 2100MHz para subida y bajada de datos respectivamente. En 700MHz existen muchas variantes, por eso no hay que conformarse al leer en las especificaciones que un teléfono funciona con LTE 700MHz. Para evitar confusiones, todas las bandas de LTE se les asignó un número. De hecho la banda en AWS es la banda 4, mientras que la banda que se va a usar en Argentina en 700MHz es la banda 17.

En resumen, las redes 4G de Argentina van a implementarse en las bandas 4 y 17. La banda 4 (que es una frecuencia alta) se va a usar en centros urbanos. La banda 17 (que es una frecuencia baja) se va a aprovechar para dar servicio a zonas rurales o pueblos chicos.

Hay que resaltar que a medida que el 4G se convierta en el estándar (como lo son 2G y 3G hoy en día), las bandas usadas para 2G y 3G se van a usar para 4G también. Por ello, podemos decir que Argentina también va a usar estas bandas para 4G. Estas bandas tienen los números 2 (1900MHz) y 5 (850MHz). Es decir que Argentina se van a usar las bandas 2, 4, 5 y 17 para LTE.

Fases de implementación

Como parte del contrato de licencia de las nuevas bandas para 4G, los poseedores de las mismas tienen plazos para ofrecer el servicio correspondiente. Las fases del despliegue de la nueva red se ven a continuación.

Screen Shot 2015-01-05 at 2.46.50 PM

Dado que las primeras fases requieren la cobertura de ciudades grandes, es de esperar que la banda 4 se utilice para ello.

Teléfonos compatibles

Dado el resumen dado arriba, los teléfonos con las bandas de LTE 2, 4, 5 y 17 van a funcionar en Argentina. Pero al inicio de la implementación de las redes 4G, solo la banda 4 va a usarse, seguida por la banda 17.

Todo dicho así es muy simple. El problema es que los fabricantes de teléfonos no van a proveer de teléfonos con soporte para todos los mercados. Hay que notar que hasta el momento hay 44 posibles bandas de LTE. Obviamente si uno adquiere el equipo a través de uno de los operadores, es de esperar que ese teléfono funcione en sus respectivas redes.

Para los que quieran traer equipos del extranjero, vayan sabiendo que van a tener dolores de cabeza. Uno de los factores principales es la fragmentación en el uso de las bandas en la región. Por ejemplo, Brasil y Chile usan la banda 7 en este momento, Paraguay 2 y 4, en Europa las bandas 3, 7 y 20, en Estados Unidos 2, 4, 5, 12, 13, 17, 25, 41. Ver lista completa de bandas por operador y país aquí.

El único equipo que da soporte a todas las bandas de Argentina es el iPhone 6 y 6 plus. Otros teléfonos iPhone, Android, Windows Phone o Blackberry proveen un soporte fragmentado, dependiendo del país de procedencia del equipo. Los equipos vendidos para Estados Unidos generalmente tienen las bandas 4 y 17.

Por eso hay que tener el ojo bien abierto. Limitándonos entre las bandas 4 y 17 damos unos ejemplos. iPhone 5c modelos A1532 y A1456, iPhone 5s modelos A1533 y A1453 , y iPhone 5 modelo A1428 proveen soporte en las bandas 4 y 17, pero no todos los modelos.  Para dar un ejemplo en Android, el Nexus 6 versión de EEUU provee soporte ambas bandas, mientras que el Nexus 6 para el resto del mundo no provee soporte para ninguna de las bandas usadas an Argentina. El Motorola Moto X 2014 tiene la banda 4 en todas sus versiones estadounidenses, pero el modelo europeo no posee ninguna de las bandas argentinas.

Mejora general en los servicios de celular

Si bien 4G provee velocidades de transferencias de datos de hasta 225Mbps, el hecho que se esté implementando en bandas de frecuencia distintas a las usadas para los servicios actuales de telefonía celular va a beneficiar a los usuarios en general. Los usuarios de 4G van a tener un espectro limpio al inicio (aunque cobertura limitada). Además 4G usa el espectro mucho más eficientemente que las tecnologías anteriores. A medida que la adopción de 4G crezca, el uso de la actual infraestructura de 3G y 2G van a ser explotada por menos usuarios. Por lo tanto, los usuarios de 2G y 3G se van a beneficiar.

Claramente estos beneficios se van a notar a medida que las empresas desplieguen la red 4G y empiecen a migrar a sus usuarios hacia 4G. Esto, por desgracia, va a llevar un par de años. Lo importante aquí es que se dio el primer paso.

Article, English

Whatsapp is just retrograde

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Here is the thing: I’m nicely sitting on my cough browsing the web with my tablet. Suddenly, I get a Whatsapp message. I’m giving no other option than grabbing my phone and attend the received message.

Same situation at work: I sit at my desk, receive a Whatsapp message and even when I have two monitors and a full-fledged keyboard, Whatsapp forces me to tap the tiny screen of my phone.

Why the heck does not Whatsapp provide multi-device support? This is not rocket science, any other basic messaging platform gives this facility.

Honestly, I haven’t given up on Whatsapp yet because of its popularity. I tried to convince some of my contacts to ditch it, but not everyone really seems to have the issues I have with it. Here is a summary with the pros and cons of this retrograde service. Sure, moving people to yet another platform is simply cumbersome.

A web interface for Whatsapp is being rumored for quite a while. But until that happens I will still be swearing Whatsapp and its users for this.

Article, English

Waze

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At a first glance, Waze looks like a traditional GPS navigation app. Once you start using it you can start seeing some interesting functionality. I will describe some of this functionality in this post.

Social

The first difference with any traditional navigation software is that you can have friends, and share with them your rides, chat with them, etc. Also, you can interact with other users of the service by reporting traffic issues along your way. This crowdsourcing of the traffic information allows all the users of the service to know what the traffic conditions are and use that info to, for instance, optimize their route. Another useful feature is that users can report the gasoline prices on the way.

Fun

As an incentive to use the service as much as possible, you may be involved in some competitions. For instance you can team up with fellow wazers to collect points. These points are collected by means of amulets you find on your way. Sure, it is far from being functional to the use that a standard user of a GPS navigation app will expect, but it keeps you busy and entertained while using Waze.

Collaborative

Waze provides some basic mapping infrastructure. So the maps still may suffer from defects such as incomplete or incorrect information. Users can then report problems with the maps so that Waze can take care of fixing it. The interesting thing is that these backend fixing actions can also be done by regular users. They can fix issues by themselves thereby helping all the other users in a more effective manner. This is particularly useful for far away places where mapping is not profitable for the state of art companies providing mapping solutions.

Some caveats

The usage of this app has some disadvantages for standard users. Here are a few are listed.

  • You need a working data connection. The app cannot do offline routing. However, it is not a data hog once is setup. For a 300km ride it will use about 10MB of data. Not bad at all but it may be deterring you from using the app, especially if you need to pay roaming fees for that data traffic.
  • Your device needs to be running. A car charger is a must if you want to use it for long rides. Dimming the screen (or even turning it off) can be measures that can help to keep your juice from draining.
  • The app needs to be started every time you hop on your car. Yes, if you want to take advantage of the service you need to start the app. That means taking your device, fixing it to a holder, connecting the charger and start the app. This can be time-consuming and too cumbersome to do every time you start driving your car.
  • GPS navigation experience is not that great. The app does its thing as a navigation system. However, if you ever used other services you will miss some important features. An example is lane guidance. The map graphics also leave a lot to be desired.

Download

The app is available for free from the app stores of the most popular mobile OSes (iOS, Android, Windows). If you are a passionate driver, willing to help your fellow drivers, you will most likely enjoy using the service. Head on to Waze website to start having fun.

Article, English

Frequency band explosion amid LTE

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For mobile telephones there have been traditionally 4 frequency bands for GSM. These are known as 850, 900, 1800 and 1900. These numbers represent the frequency range (in MHz) that the band uses. As a rule of thumb, the Americas (except Brazil) use the 850 and 1900 bands, while the rest of the world use the 900 and 1800 bands. A comprehensive explanation is available in this wiki-page.

For WCDMA networks (aka 3G), Europe introduced the 2100 band, while in USA the so-called AWS band was created (that uses some spectrum in the 1700MHz and 2100MHz ranges) for T-Mobile to deploy its 3G network. As GSM networks age, GSM bands are used for WCDMA networks. A more detailed description of 3G bands is available here.

Due to the ubiquitous use of mobile services, the spectrum in the 6 above-mentioned bands is expected to be insufficient. This is especially true since 2G and 3G services will become legacy. That’s why that in the wake of LTE (aka 4G) more bands to accommodate the expected growth of mobile communications are being created. This was also possible due to the liberation of the spectrum used by analog services (analog TV mainly). Note that basically each country has the power to decide how to assign the freed spectrum. Due to this anarchy, as many as 34 new bands were created to date. See LTE bands.

The exponential growth in the number of bands is making it hard to manufacture radio hardware that can support all these bands. In fact, this was an issue even to give support to the 4 GSM bands: only high-end handsets will give you the luxury of the quad-band support, while feature phones will be market-specific. This was also due to certification issues: for example, to release a device that has to operate in the American market bands, it will certainly need an FCC stamp before it can be shipped.

As for LTE global devices, we can list the iPhone. Although it is not that obvious to final consumer, there are three variants of the iPhone to be able to cover all the LTE bands in use to date. Also, some countries are being quite deliberate to when it comes to decide what bands will be licensed for LTE use. An exception is Europe: all countries have already decided what bands will be used within the block, while in Asia and the Americas each country is going its own way, creating a lot of fragmentation on the bands to use. This will have a strong effect once roaming from one country to the other once LTE becomes state-of-the-art.