THE DEVELOPMENT OF PERSONAL COMMUNICATION SERVICES UNDER THE AUSPICESOF EXISTING NETWORK TECHNOLOGIES

The concept of personal communication services (PCS) is only now begin ning to take shape. In the past, PCS was described as services that we re planned in certain frequency bands, such as in the 900 MHz narrowba nd licenses auctioned to the paging carriers (termed narrowband PCS) a nd the 1800 MHz frequencies auctioned for Voice services. PCS has also been used as a synonym for certain technology standards like IS-136 T DMA, GSM (also known as DCS-1800), or 15-95 CDMA. However, the industr y is now realizing that PCS is really a collection of voice and/or dat a services that meet the following minimum criteria: a single address or contact number to locate a user, the ability of the network to loca te the recipient of the message, true universal coverage, and the inde pendence of defined services from delivery mechanisms and technology. It can be argued that no single network or technology can address all these different attributes at an attractive price for all customers. T his has caused existing service providers to invest in the internetwor king of different wide area networks (WANs), establishment of standard ized platforms for service creation, and development of content-aware smart applications. This article looks at several such developments in the context of the efforts underway at RAM Mobile Data USA L.P. to pr ovide PCS using the Mobitex(R) technology as its core. This article an alyzes the Multi-Network Access Services (MNAS) which allow interconne ction of several WANs, including satellite, circuit-switched cellular (CSC), public switched telephone network (PSTN), and paging networks. The approach is flexible enough to allow interconnection to additional networks that may be required in the future. This article also takes a look al the efforts on development of smart applications and service s that are content-aware but independent of the underlying network tec hnologies used. The proposed approach allows customers to use a single application to access similar services over multiple networks.