Abstract: A multimedia messaging system for use in providing voice mail, fax mail, e-mail, notification services, etc. over telephony lines is disclosed in which the system is adaptable for clustering to a single telephony-equipped switch. Multiple back-end systems can be added to the single telephony equipped switch such that the back-end machines operate the same as they would in stand-alone mode, thus making the cluster transparent to the back-end machines.

Abstract: A memory system and management method for optimized dynamic memory allocation are disclosed. A memory manager requests a large area of memory from an operating system, and from the viewpoint of the operating system, that memory is fixed. That fixed memory area is then divided up into an integral number of classes, e.g. by the memory manager. Each memory class includes same-size blocks of memory linked together by pointers. The memory block sizes are different for each class, and the sizes of the different class memory blocks are selected to conform to the CPU and memory access bus hardware (e.g. align with a bus bit width) as well as to accommodate the various sizes of data expected to be processed for a particular application. The memory manager maintains a separate, linked list of unused blocks for each class. Each memory block is zeroed initially and after release by a process previously assigned to it. When a block of memory is assigned to a particular process, a flag is set to indicate that it is in use.

Abstract: A flexible, object-oriented call processor is employed in a wide range of messaging environments (e.g. voice messaging, facsimile mail, notification and electronic mail) to provide any number and type of messaging service. Call processing procedures can be changed or adapted to provide a new or different messaging service without rewriting large amounts of software or redesigning the messaging system. Various call processing primitives are established to perform various call processing services in a messaging application, with each to primitive performing a single operation. Sets of parameters are also defined for different types of call processing services and different subscribers. A service state table corresponding to a sequence of logical states is set up to provide the requested call processing service. Once a requested call processing service is identified in response to a subscriber call, the call processor executes the service logic in the corresponding service state table.