Le 3rd generation partnership project (3GPP) brings together seven telecommunications standards development organizations (ARIB, ATIS, CCSA, ETSI, TSDSI, TTA, TTC), known as “organizational partners”. It provides its members with a stable environment to produce the reports and specifications that define 3GPP technologies.
The project covers cellular telecommunications technologies, including radio access, backbone and quality of service, to provide a complete description of the system.
The 3GPP specifications also provide the limits for non-radio access to the core network as well as interoperability with non-3GPP networks.
The three groups of 3GPP technical specifications are:
- Radio access networks
- Services & Systems Aspects
- Core network and terminals
The 3GPP technologies of these groups are constantly evolving with the generations of commercial cellular / mobile systems. With the work on LTE, LTE-Advanced, LTE Advanced Pro and 5G, 3GPP has become the main focus for the development of the vast majority of mobile systems after 3G.
Although these different generations have become a descriptor for each type of network under discussion, actual progress on 3GPP standards is measured by the milestones achieved in particular versions. New features are then “feature-locked” and are ready to be implemented when a release is complete. 3GPP works on a number of versions in parallel, starting future work well before the current version is completed.
Although this adds some complexity to the work of groups, such a way of working ensures that progress is continuous and stable.
Backward compatibility
The main goal of all 3GPP versions is to make the system backward and downstream compatible to ensure that endless equipment life abruptly. A good example of this principle was the priority given to backward compatibility between LTE and LTE-Advanced, so that an LTE-Advanced terminal could operate in an LTE cell, and an LTE terminal with an LTE-Advanced cell.
Generations of mobile systems
| 1G | Analog technology from the 1980s. |
| 2G | First digital system deployed in the 1990s allowing voice, SMS and data services. |
| 3G | The 3GPP 3G system is based on the advanced GSM core networks and the radio access technologies they support. |
| 3G / 4G | LTE and LTE-Advanced have crossed the “generational frontier” by enabling new generations of capabilities. With their high-speed data transmission capability, significant spectral efficiency, and the adoption of advanced radio techniques, their emergence has been the basis for all new mobile systems from version 8 onwards. |
| 5G | 5G brings another major technological step forward, with the creation of a “New Radio” (NR). |
Milestone of the radio access network
The technical specifications of the 3GPP “Radio Access Network” group ensure that systems based on 3GPP specifications can be rapidly developed and deployed by ensuring worldwide roaming of equipment.
Each 3GPP radio access technology aims to reduce the complexity and avoid fragmentation of the technologies offered.
Evolution of the core network
GSM networks initially used switched-mode telephony with the addition of packet mode with GPRS. In the UMTS architecture, this dual domain concept has been retained on the core network side. Some parts of the network have evolved, but the concept has remained very similar.
Considering the evolution of the 3G system to LTE, the 3GPP community decided to use IP as a key protocol to transport all services. It was therefore agreed that the Evolved Packet Core (EPC) would not have a switched mode domain but that the EPC should be an evolution of the packet mode architecture used in GPRS / UMTS.
This decision had consequences on the architecture itself but also on the way in which the services were provided. The traditional use of circuit mode to transport voice and short messages had to be replaced in the long term by only IP-based solutions.
