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Previous generations of mobile technology have also been kick‐started by the agreement of a relevant IMT. While IMT‐2020 led to 5G and an agreed, unified approach spearheaded by the 3GPP, earlier IMTs have given rise to different approaches to achieve the same desired outcomes.

For example, IMT‐Advanced provided requirements for the 4th generation of mobile technology (4G), but there were several approaches that could have met these. Long‐term evolution – otherwise known as “LTE” – was just one example; Mobile WiMAX and Ultra Mobile Broadband, among others, were, for several years, considered as viable alternatives, although only two remained as candidate systems – LTE and Mobile WiMAX [4]. Similarly, the earlier IMT‐2000 recommendations, which gave rise to 3G, also generated several different candidate solutions, some of which saw commercial operation.

3GPP was originally founded in 1998, with the aim of bringing together a number of foundational partners to collaborate on common standards to meet the requirements of IMT‐2000 and the realization of what became known as 3G [5]. 3GPP based its efforts on the evolution of the existing GSM (the Global System for Mobile Communications) standards for 2G, originally driven through the European Telecommunications Standards Institute, or ETSI. The partnership agreement brought together organizations that had previously, either individually or via different collaboration groups, contributed to earlier generations of mobile technology.

3GPP’s efforts resulted in a set of standards for 3G – the Universal Mobile Telecommunications System (UMTS) – whose work has ultimately led to today’s 5G. However, a parallel organization (3GPP2) shadowed the work of the original 3GPP during this period, considering the perspectives of a different group of stakeholders, some of which proposed alternative candidates for 3G, such as CDMA2000, to meet the same IMT‐2000 requirements.

CDMA2000 was adopted in the United States, South Korea, Japan, China, and Canada, for example, but saw little deployment outside these countries, as most nations favored the UMTS standards defined by 3GPP. 3GPP2 subsequently pursued initiatives to create standards for the 4th generation of mobile; however, these met with little success, because, as far as IMT‐Advanced is concerned, LTE won the race and became the default commercial vehicle for 4G.

The alternatives also failed to gather significant commercial momentum (although some such as Mobile WiMAX did reach deployment in several countries) and, eventually, fell by the wayside. Different approaches to IMTs are illustrated in Figure 3.1.

Figure 3.1 IMTs and different generations of mobile network technology.

As a result, 3GPP2 effectively ceased operations in around 2013 and is now a dormant organization. This latter point may be highly significant for the future, as we shall see.

Even before this, while GSM had been promoted for 2G by ETSI, other approaches had been developed by alternative standards organizations, resulting in multiple 2G standards that enjoyed widespread adoption for a long period of time.

5G is thus something of an anomaly in the history of the mobile industry, as it represented a coordinated, single global approach to the realization of the IMT‐2020 demands. For each previous generation, there was not, at the outset, necessarily an obvious winner or a single unified approach. Will 6G see a return to such a situation, or will a global effort prevail? There are many reasons to think that 6G could well lead to fragmentation in mobile standardization. Why?