Since about 2011, talk in policy circles about how to encourage a faster and definitive replacement of the legacy time division multiple public switched network has been becoming more serious. 

The PSTN transition sometimes in the past has been described as “shutting down the PSTN,” a way of stating the issue that is rather more inflammatory than some observers would say is helpful.

In fact, the PSTN virtually has to be superseded by the newer IP network, for fundamental business reasons. As was true for analog and the first digital mobile network, the new services people want all are based on different technologies. For the PSTN and its users and providers, it increasingly is IP technology that underpins the services people want to use.

The obverse also is true. As fewer and fewer customers remain on the older legacy network, the higher the allocated costs that must be shared by fewer customers, the higher the percentage of stranded assets and the higher the costs of maintenance.

As always happens when a major new technology replaces an older technology, it becomes harder, over time, to upgrade core software and hardware, or even to buy replacement units and parts. In one sense, the shutdown of the PSTN is not unlike earlier technology transitions of core switching technology. 

But the big difference is that the transition to a new IP-based network occurs under radically different circumstances. Not only are markets much more competitive, but the very way IP networks work have key implications. Among the most significant of those differences is the logical separation of network access and transport from applications. 

That has key implications for potential revenue and hence for regulatory frameworks as well.

Mobile executives routinely replace older networks, and already have shut down the first generation mobile network. The sunset of the second and third generation networks also will happen. Verizon, for example, has said it will turn off both the 2G and 3G networks by 2021.

The first generation U.S. analog network was shut down in 2008, for example. The second generation TDM network will be shut down in 2017, according to AT&T (News - Alert).

But there will be lots of political squabbles about how the regulatory framework might need to be adjusted as the PSTN sunset is handled. Among the issues are a global shift of usage to mobile networks, which means the potential landline market is not as big as it once was.

So there are logical reasons for firms such as Verizon (News - Alert) or AT&T, where they continue to own fixed network assets in rural or low-density areas, to consider new technologies to provide services to their customers. Executives at both firms have talked about using Long Term Evolution fourth generation networks to provide services where that network is more efficient than the fixed network.

Some will be unhappy about that. But our notions of “what has to be done” also must be shaped by “how” to best accomplish our goals. The best network might not always be the fixed network, even as that has proven to be true all over the rest of the world where wireless or mobile networks are the logical choice for supplying advanced new services at the fastest possible speed, at the lowest possible overall cost. Want to learn more about the latest in communications and technology? Then be sure to attend ITEXPO Miami 2013, happening now in Miami, Florida.  Stay in touch with everything happening at ITEXPO (News - Alert). Follow us on Twitter.