Carriers have a number of reasons for completely turning down older technologies.
- First, wireless spectrum used by cellular services is expensive. Acquiring spectrum licenses at auctions from government regulators – such as the Federal Communications Commission (FCC) in the USA – often can cost billions of dollars for nationwide licenses. This expensive spectrum must be used as efficiently as possible to provide a good return on that large investment. New cellular technologies (i.e., “Generations”) provide opportunity to use this expensive resource more effectively, since the new data encoding protocols are far more spectrum-efficient than older generation protocols.
- The inefficiency of older technologies is particularly exposed as smartphones and other data-hungry consumer devices had been deployed, creating a demand for higher data throughput. M2M and IoT applications have to compete for the wireless resources that are shared by all the consumers. This puts pressure on the carriers to remove older, less spectrum-efficient, technologies and replace them with next-generation technologies that use more spectrum-efficient protocols.
- Control messages in cellular networks have evolved from using unique signaling transports and protocols – such as Signaling System Seven (SS7) that used expensive infrastructure hardware – to more modern control message protocols using Internet Protocol (IP), which are far less expensive to deploy and maintain. This change to use IP-based control plane signaling was required with 4G LTE.