Abstract: Systems, methods, apparatus and articles of manufacture are disclosed for tracking, propagation and matching of messages pertaining to the interest in and availability of services across autonomous service domains In one embodiment of the invention, a system of distributed, federated service domains in a service-oriented environment is provided wherein each service domain comprises: a plurality of locally provided services; a plurality of service requesters; and a service registry comprising descriptions of: one or more locally provided services; and one or more requested services, each of the requested services being one of: a fulfilled reference to a foreign service; and an unfulfilled reference to a foreign service.

Abstract: Methods for serving data include maintaining an incomplete version of an object at a server and at least one fragment at the server. In response to a request for the object from a client, the incomplete version of the object, an identifier for a fragment comprising a portion of the objects and a position for the fragment within the object are sent to the client. After receiving the incomplete version of the object, the identifier, and the position, the client requests the fragment from the server using the identifier. The object is constructed by including the fragment in the incomplete version of the object in a location specified by the position.

Abstract: Techniques for automatically detecting similar subsets (e.g., fragments) in electronic documents such as dynamic content-based data, e.g., web pages. The techniques of the invention may perform a systematic analysis of the web pages with respect to one or more of their information sharing behavior, their personalization characteristics, and their change pattern over time. Thus, the invention may be applied to discover fragments in web pages of web sites that are most beneficial for caching the contents of the web site. The present invention also comprises techniques for publishing electronic documents with automatic fragment detection.

Abstract: Techniques are disclosed for managing storage of objects of sizes smaller than a storage transfer unit in a computer system. A plurality of storage transfer units are maintained in a first storage medium (e.g., disk storage) organized by a quantity of free space in a storage transfer unit. A cache is maintained in a second storage medium (e.g., main memory), the cache including a copy of at least one of the plurality of storage transfer units. In response to a request to store an object of a size less than a storage transfer unit, the technique searches for a cached storage transfer unit with sufficient free space to store the object. If no such cached storage transfer unit can be found, the technique identifies an uncached storage transfer unit with sufficient free space to store the object and stores a copy of the identified storage transfer unit in the cache.

Abstract: In a system having a plurality of caches, a method for maintaining cached objects includes storing an object in a plurality of caches. In response to a request to update the object, a future invalidation time is determined when the object should be invalidated in caches currently storing the object. Updating of the object is delayed until the invalidation time has passed.

Abstract: A method for communicating information from a first computing node to at least one of the following: a storage device and a second computing node. The first computing node is monitored to collect at least one estimate of available resources, and based on this estimate, an amount of data collected is modified. Then, the collected data is sent to at least one of the following: the storage device and the second computing node. This invention also provides for the determination of an optimum batch size for aggregating data wherein, for a number of batch sizes, costs are estimated for sending batched information to persistent storage and for losing batched data. Then, the optimum batch size is selected from the number of different batch sizes based on sums of these costs. This invention also provides for selective compression of data, wherein it is determined which of a number of compression algorithms do not incur an overhead that exceeds available resources.

Abstract: Techniques are disclosed for generation and refinement of service descriptions based on records of invocations of the services, i.e., service description refinement based on actual service use. For example, a method for describing one or more services in a service-oriented environment comprised of one or more clients invoking the one or more services comprises the following steps. An initial description is established for at least one of the one or more services. Information is collected from one or more service invocations including at least one of a client identity, a value of at least one parameter, a return value, and an execution time. The information is analyzed to refine the description.

Abstract: Techniques for cache management including cache replacement are provided. In one aspect, a distributed caching technique of the invention comprises the use of a central cache and one or more local caches. The central cache communicates with the one or more local caches and coordinates updates to the local caches, including cache replacement. The invention also provides techniques for adaptively determining holding times associated with data storage applications such as those involving caches.

Abstract: A technique for delivering content in a client-server system based on a request received at a computing device from a client includes determining a current load on a next-level computing device of a hierarchy. When this current load is such that a response time for delivery of the request from the next-level computing device would increase above a given threshold, a client type associated with the request is checked and, when the client type indicates that the client is below a given priority level, content to be delivered to the client in response to the request is personalized at the receiving computing device. When the current load is such that the response time would not increase above a given threshold, the request is sent from the receiving computing device to the next-level computing device and the content to be delivered is personalized at the next-level computing device.

Abstract: Techniques for coordinating updates to replicated data are disclosed. For example, in a system comprised of a plurality of nodes, a method for maintaining consistent copies of data across said nodes comprises the following steps. A copy of an object o1 is maintained by a plurality of nodes. In response to a request r1 to update a copy of object o1, a message is sent to at least some of said plurality of nodes instructing a node receiving the message to invalidate its copy of object o1. In response to a node n1 receiving an invalidation message arising from r1 wherein n1 is processing another request r2 to update object o1, requests r1 and r2 are coordinated to prevent the requests from causing conflicting updates or invalidations.

Abstract: Techniques are disclosed for load balancing based on call length in networks such as those networks handling telephony applications. By way of example, one method for directing requests associated with calls to servers in a system comprised of a network routing calls between at least one caller and at least one receiver wherein the network comprises a load balancer sending requests to a plurality of servers comprises the following steps. A first request of a call is received. A server s1 is selected to receive the request based on an estimated duration of the call. Another method for directing requests associated with calls to servers in a system comprised of a network routing calls between at least one caller and at least one receiver wherein the network comprises a load balancer sending requests to a plurality of servers comprises the following steps. Information is maintained regarding load assigned to a plurality of servers. A first request of a call is received.

Abstract: Techniques are disclosed for load balancing in networks such as those networks handling telephony applications. By way of example, a method for directing requests associated with calls to servers in a system comprised of a network routing calls between a plurality of nodes wherein a node participates in a call as a caller or a receiver and wherein a load balancer sends requests associated with calls to a plurality of servers comprises the following steps. A request associated with a node belonging to a group including a plurality of nodes is received. A server is selected to receive the request. A subsequent request is received. A determination is made whether or not the subsequent request is associated with a node belonging to the group. The subsequent request is sent to the server based on determining that the subsequent request is associated with a node belonging to the group.

Abstract: Techniques are disclosed for load balancing in networks such as those networks handling telephony applications. By way of example, such techniques direct requests associated with calls to servers in a system comprised of a network routing calls between a plurality of callers and at least one receiver wherein a load balancer sends requests associated with calls to a plurality of servers as follows. A request associated with a call, a caller, or a receiver is received, depending on the particular load balancing technique. A server is selected to receive the request. A subsequent request is received. A determination is made whether or not the subsequent request is associated with the call, the caller, or the receiver, depending on the particular load balancing technique. The subsequent request is sent to the server based on determining that the subsequent request is associated with the call, the caller, or the receiver, again depending on the particular load balancing technique.

Abstract: Methods for serving data include maintaining an incomplete version of an object at a server and at least one fragment at the server. In response to a request for the object from a client, the incomplete version of the object, an identifier for a fragment comprising a portion of the object, and a position for the fragment within the object are sent to the client. After receiving the incomplete version of the object, the identifier, and the position, the client requests the fragment from the server using the identifier. The object is constructed by including the fragment in the incomplete version of the object in a location specified by the position.

Abstract: Techniques for maintaining consistent replicas of data are disclosed. By way of example, a method for managing copies of objects within caches, in a system including multiple caches, includes the following steps. Consistent copies of objects are maintained within the caches. A home cache for each object is maintained, wherein the home cache maintains information identifying other caches likely containing a copy of the object. In response to a request to update an object, the home cache for the object is contacted to identify other caches which might have copies of the object.

Abstract: Techniques are disclosed for adaptively determining trust in client-server environments. By way of example, a method for assigning a trust level to a client in a client-server environment including at least one client communicating with a plurality of servers includes the following steps. Information associated with a server s1 and a server s2 different from s1 is obtained regarding a request r1 sent by a client and received by s1 and a request r2 sent by the client and received by s2. The obtained information is utilized to assign at least one trust level to the client.

Abstract: Automated techniques are disclosed for coordinating request or transaction processing in a data processing system. For example, a technique for handling requests in a data processing system comprises the following steps. A compound request comprising at least two individual requests of different types is received. An individual request r1 of the compound request is placed on a queue for requests of type t1, wherein t1 is the request type of r1. After r1 has reached the front of the queue, it is determined if at least one individual request of said compound request can execute. The compound request is executed if it is determined that all individual requests of the compound request can execute.

Abstract: Automated techniques are disclosed for coordinating request or transaction processing in a data processing system. For example, a technique for handling compound requests, in a system comprising multiple nodes for executing requests in which an individual request is associated with a particular node, comprises the following steps. A compound request comprising at least two individual requests associated with a same node is received. It is determined if both of the at least two individual requests are executable. The compound request is executed if it is determined that all individual requests of the compound request can execute.

Abstract: Techniques are disclosed for integrating a model-based approach with a search-based approach for automatic configuration of a computer system. For example, in one such technique, a method for automatically configuring at least one computer system includes obtaining at least one model describing one or more effects of at least one configuration parameter on a behavior of the computer system, and modifying a process for searching for at least one acceptable value for the configuration parameter based on the model.

Abstract: Techniques for efficiently authenticating multiple objects and clustering objects based on access patterns are provided. For example, in an illustrative aspect of the invention, a technique for generating and/or reading authentication information, wherein the authentication information provides evidence that a plurality of objects were one of generated and sent by an entity, comprises using one or more object access patterns indicative of whether at least two of the plurality of objects are accessed within a similar time period to group objects together to reduce an overhead for at least one of generating and reading the authentication information.