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Method for Forward Transitive Fully Connected Collection Management Disclosure Number: IPCOM000036969D
Original Publication Date: 1989-Nov-01
Included in the Prior Art Database: 2005-Jan-29
Document File: 6 page(s) / 22K

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Related People

Harris, JF: AUTHOR [+3]


Transparent Services Access Facility (TSAF) currently manages collections in VM/SP.

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Method for Forward Transitive Fully Connected Collection Management

Transparent Services Access Facility (TSAF) currently manages collections in VM/SP.

A collection is a logical subdivision of a larger network of computer processors with the following properties: Dynamic formation

Systems join and leave the collection dynamically.

Dynamic Resource identification

Resources (Transaction Programs) can dynamically

identify themselves within the collection.

Unique names (flat name space) for global resources.

Global resource names are unique within the


Transparent Services Access Facility (TSAF), which is a VM/SP component, currently manages collection formation of up to 8 processors and line flows between the processors.

Collection management in TSAF is based on several processes: a join protocol, clock synchronization, atomic broadcast and collection monitoring.

The join protocol determines for each link-connected pair of processors which one should join the other.

Clock synchronization provides a basis for collection-wide timer- based functions by keeping all of the logical clocks throughout the collection within a bounded differential of each other. This synchronization must be established and maintained for all nodes in the collection in order for timeout-based broadcasts to work correctly.

Atomic broadcast is a method for accurately (and simultaneously, if necessary) installing replicated data throughout the collection.

Collection monitoring consists of the application of timeouts to the aforementioned processes in addition to the monitoring of links. In order to form a TSAF collection and to maintain a fully formed collection, all joined nodes must participate accurately and in a timely fashion relative to time parameters agreed upon via atomic broadcast.

A method is needed to reliably and consistently distribute data about the members and resources of a collection of processors within a network of computer processors in order to manage the collection formation and activities. With the current mechanisms used in TSAF, it is currently impossible to increase the size of a collection. They are also not reliable as the collection approaches its limit size. This mechanism removes this limitation.

This mechanism addresses the key aspects of managing a collection where a program such as VTAM manages the overall network flows. With the use of this mechanism, APPC/VM VTAM Support (AVS) can manage the collection. This


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allows TSAF to be bypassed, thus increasing system performance and system reliability. This mechanism also increases the size of the collection beyond the TSAF-imposed limits. This mechanism can also be used in TSAF to replace its collection management mechanisms in order to increase the collection size.

Processor is referred to as a "node" or a "system". The features of this mechanism are as follows: Dynamic collection join and dynamic collection leave is

supported in a manner that, externally, is...