IP Telephony Cookbook by Saverio Niccolini, Jorg Ott, et al - HTML preview

Improved availability

There are many aspects of availability. Lowering the cost can make telephony more available to low-budget activities. Redundancy can provide as good as (or even better) reliability than traditional telephony. Integrating telephony with location-based computing and group-awareness systems can make the communication partners much more ‘available’, or provide the means to transfer communication to a point in time where it is more appropriate than the usual interrupt-driven telephone call;