Network service providers are slowly migrating from legacy network to full IP networks. Some service providers already run 100% IP based network with only TDM and SS7 connectivity to service providers that are not IP based. Access devices developers have realized that migration from PSTN to NGN will take some time and as a result have decided to support both networks on a single device. Skype dual phone 3088 is a very good intelligent example of such access devices. With this device the user is able to connect on Skype without using the PC. This is a huge benefit on power saving. All what the user needs is connectivity to Internet. This technology integrates PSTN with Skype. This means the user can receive and dial out both Skype and PSTN calls on the same device. This device also uses the well known DECT technology which allows the user to move around with the phone without being restricted by the cord. Imagine being irrigating the garden while speaking with a Skype user who might be in another country talking free of charge. The other user/ callee can be connected on any Skype device even the computer.
The only shortfall of this device is that it uses Skype proprietary protocol. This means for subscribers toggling between SIP service providers and Skype need a separate device for SIP. This is a disadvantage as VOIP devices do not come very cheap. Currently technology options in the market allow urers to choose between SIP+ PSTN and Skype + PSTN integration, based on the calling needs. SIP service providers and Skype charge different tariffs from destination to destination. The user will need to consider tariffs for the destinations of interest before choosing the best technology combination. Both of these devices are quite smart as the subscriber receives and dial out using either VOIP or PSTN number. The other disadvantage of Skype over SIP is that Skype can not terminate calls originating from other networks in destinations where Skype do not have phone numbers. Skype users though can still benefit from reasonable outbound call tariffs which make the source of phone bill. It is still wise to invest on Skype device as Skype destinations where numbers are provided also seem to be growing fast.
In the next article we will present bandwidth constraints that need to be taken into consideration when deploying these technologies at a large scale.
Source by Zwelandile Mbebe