Wireless Point-to-MultiPoint (PtMP) networks use a finite frequency spectrum as a shared medium to convey data traffic to multiple users from a single location. The spectrum used for transmission enables the delivery of a certain amount of traffic from a single Base Station to multiple remote Subscriber Units (SU) and vice versa.
In order to reduce the amount of valuable spectrum needed in any given PtMP network, the SUs utilize the spectrum resources only when they need to send or receive data. In this way, more SUs can share a common spectrum, while each of them transmits or receives in its turn a burst of traffic, for a period of time according to its needs.
The main advantage with a PtMP network is its ability to optimize use of the frequency spectrum as a shared medium, and send the maximum possible traffic upon demand. Yet, similar to any shared medium, there are periods when the amount of traffic generated by the SUs is much greater than can be allowed. This phenomena is very common in ‘rush hour’ when many subscribers access the network at the same time. In these overload conditions, the active SUs send or receive smaller amounts of data than they would normally.
Different types of subscribers react differently to this scenario: residential subscribers who usually seek to pay as little as possible are insensitive to the temporary reduction in their link capacity. Enterprise subscribers, on the other hand, or even Small to Medium Enterprises (SMEs), whose productivity highly depends on the data connectivity to the network, are very sensitive to the level of capacity at any given moment, and are prepared to pay the service provider extra (bringing a higher ARPU) in order to secure a Committed Information Rate (CIR) 24 hours a day, 7 days a week. Moreover, this lucrative type of subscriber monitors the level of Service Level Agreement (SLA) they are subscribed for and accordingly ranks the service providers.
The need for CIR is not just related to the type of subscriber, but also to the application involved. For example, Video Surveillance traffic that is transmitted over a PtMP in parallel with other data or internet subscribers should be transmitted over a link with secured CIR to guarantee performance – otherwise during network traffic overload, it would be vulnerable to pixilation and jitter.
Not many players in the PtMP industry can support the demand for CIR, including WiFi based solutions, as CIR requires the Base Station to centrally manage the Air-interface resources, whereas WiFi air protocol management is distributed among the end-points.
RADWIN’s Pro family, encompassing the JET-Pro, RW 5000-Pro and SU-Pro enables service providers to guarantee a minimum level of capacity upon subscriber demand by setting an appropriate CIR level per Subscriber Unit in both downlink and uplink directions. The CIR feature does not consume any air resources and enables the service providers to increase their ARPU by addressing the requirements of this lucrative market segment.