GSM is the second generation’s system for mobile telephony that is used today in parallel with the third generation (3G) and the newly built 4G. In 2011, GSM still had more users globally than the newer network for mobile traffic. GSM stands for Global System for Mobile communication and is a digital mobile network that is primarily used with mobile phones in Europe and other parts of the world. The technique uses different time division multiple access (TDMA). GSM compresses uses digitalization to compress data and sends it through a channel with two other streams of user data, with each taking place in their own time slots. A few features of GSM incudes;

  • Encryption for phone calls
  • Data networking
  • Short Message Service (SMS) for text messages and paging
  • Call forwarding
  • Caller-ID
  • Call waiting
  • Multi-party conferencing

When GSM entered the market it was aimed to create a common mobile system for all European countries as a standard. The technique has since then been developed and is today based on technique from countries outside of Europe. There are four different variations of GSM, and which one is used depends on what region you’re in.

To many GSM may seem outdated because it doesn’t really catch up with the requirement of speed in today’s apps, games, and videos. Despite of this, many countries in the world still use GSM as the main network for mobile communication.

  • GSM is the second generation’s system for mobile communication.
  • The system was commercialised in 1991 and the first network in Sweden was released in 1992.
  • GSM is run in parallel with the 4G networks.
  • There are four different GSM variations that are connected to different regions.
  • Many still commonly use the GSM network for mobile communication.
  • The requirement in today’s apps forces many users in western countries to choose 3G or 4G.
  • The fundamentals for development of GSM were terminated in 1982.

Second generation’s mobile telephony system

GSM stands for Global System for Mobile communication and is the second in row of mobile telephony systems. The system was commercialised in 1991 with it’s first launch in Finland – and came to replace the previous analogue system (NMT) in Nordic and European countries. GSM is still widely used today in roughly 100 countries including USA and Europe.

Thanks to GSM we could start sending texts, something that most of us today take for granted. The system and the standard set by CEPT has allowed for the data roaming abilities we have while travelling. The system was developed to manage things such as WAP sites and MMS. It was also in connection with GSM that SIM cards were introduced, something that everyone uses in their mobile phones.

In Europe GSM-900 and GSM-1800 are used. GSM is used in parallel with 3G and the newly built 4G network as complement. GSM also exists in four different variations; GSM-1900, GSM-1800, GSM-900 and GSM-850. This is equivalent with the megahertz that is used to transfer data and numbers within the different frequency areas.

History of GSM

Before GSM, Advanced Mobile Phone System (AMPS) was widely used in United States and Total Access Communication System (TACS) was popular in United Kingdom. Both were built with analogue technology but were unable to scale with adoption of more users. This resulted in an increased need for a more efficient cellular technology that could also work internally.

To achieve this, a group called “Speciale mobile” was created by CEPT (European post and telecommunication authorities conference)In 1982 with the mission to develop a technique for common mobile telephony system for all countries in Europe. Before the group was created, each country had developed their own systems, such as NMT in Scandinavia. CEPT also decided a few criteria’s that the system is required to meet that includes; high speed quality, international roaming support, support for handheld devices, low service cost, support for new services and ISDN capability. Representatives from 13 European countries signed an agreement in 1987 for a telecommunication standard. EU also then passed laws for GSM as a standard in European countries. The responsibilities of the project was later passed to the European Telecommunications Standards Institute (ETSI).

In 1991 services based on the GSM technique were commercialised with initial launch in Finland and later came to represent 80% of the global mobile market in 2010. The same year GSM standard frequency increased from 900 MHz to 1800 MHz. Sweden got its’ first GSM network in 1992. In the beginning GSM was a European standard but is now based on technique from countries outside of Europe which lead to today’s meaning of the acronym – global system for mobile communication. Some may refer to GSM as 2G which is an afterthought based on the third generation’s name – 3G. In 2011, there were still more users of the GSM network than the new 3G network. All the more apps, videos and similar set higher requirements on speed which ultimately makes the new generations the bigger winner in the long run.

Network composition

The network works in whole with four separate parts working together, this includes; base station subsystem (BSS), network switching subsystem (NSS) and operating and support subsystem (OSS). A mobile can connect to the network via hardware and the users SIM card provides identification to the network. The NSS is the core network and tracks caller’s location in order to enable the cellular services. The mobile carriers are the ones that own NSS and it has different components that perform different functions, such as routing calls, SMS, and storing caller account information with SIM cards. Many operators of GSM have roaming agreements with foreign carriers and this allows users to continue using their phones as they would at home.

GSM security

GSM is designed to be a secure wireless system, but it’s still not completely protected from attacks. The system uses challenge-response authentication which constitutes of providing a valid answer to a question and a password or passphrase for users. To ensure that user’s conversation is protected and private, the system has cryptographic security algorithms such as ciphers that encrypt plaintext digits.

Latest update 22/11-19