Abstract: Methods, systems, and computer program products for dynamically modifying an application program's behavior in response to changing environmental conditions (such as network changes, system changes, and so forth). The application may solicit such information, and/or may receive unsolicited environmental change notifications. In response to a change notification, the application may take one or more of the following approaches to adapt to the changing conditions: (1) alter its execution; (2) modify its use of, or control of, other cooperating application; and (3) modify the selection of application execution threads. (An application might also decide to make no changes in its behavior.

Abstract: Methods, systems and computer program products provide for establishing a connection originated by an application executing on a data processing system in a cluster of data processing systems. A dynamic network address is associated with the application at the data processing system on which the application is executing. If a request is received for the data processing system to originate a connection that is associated with the application, the connection is established utilizing the dynamic network address associated with the application as a source address for the connection.

Abstract: Methods, systems and computer program products provide communications with a plurality of application instances using a plurality of communication protocol stacks and a single Internet Protocol (IP) address. A stack is established as a routing stack associated with the single IP address. Other stacks which are associated with the single IP address are defined as candidate target stacks and an identification of candidate target stacks and the routing stack is distributed to the stacks. The routing stack is notified when an application associated with a candidate target stack listens to a port of the IP address to establish a current actual target stack. A request to establish a connection to the IP address and the port of the IP address is received and a routing table entry corresponding to the current actual target stack is created to provide a routing path from the routing stack to the current actual target stack.

Abstract: Methods, systems and computer program products provide assignment of ports for connections originated by multiple application instances executing on different data processing systems utilizing a common network address. An indication of available ports for the common network address is provided to each of the different data processing systems executing the multiple application instances. A port identified as available is selected as a port for a connection utilizing the common network address.

Abstract: An improved technique is disclosed for routing data across multiple topology subnets, and for improving the connectivity between nodes in multiple topology subnets, by using a common connection network. A new type of virtual node, referred to herein as a “global” virtual routing node or “GVRN”, is defined to represent connectivity to an underlying network that may extend beyond the boundaries of the topology subnets in the end-to-end path. This underlying network is also referred to as a “common connection network” or a “global connection network”. The present invention also defines novel techniques with which border nodes pass routing information between networks to convey connectivity to the GVRN. In many cases, use of GVRNs will result in shorter end-to-end data transmission paths.

Abstract: Systems, methods and computer program products are provided for preserving a session between an SNA application and a TN3270E server after loss of an IP network connection between the TN3270E server and a TN3270E client that is communicating with the SNA application via the SNA session.

Abstract: Methods, systems and computer program products provide for transferring a virtual Internet Protocol address (VIPA) between communication protocol stacks including at least a first communication protocol stack and a second communication protocol stack. Ownership of the VIPA is established at the second communication protocol stack and connections to the first communication protocol stack utilizing the VIPA are maintained. TCP/IP messages for the connections to the first communication protocol stack are routed through the second communication protocol stack so as to non-disruptively move the VIPA from the first communication protocol stack to the second communication protocol stack.

Abstract: Methods, systems and computer program products provide communications with a plurality of application instances using a plurality of communication protocol stacks and a single Internet Protocol (IP) address. A stack is established as a routing stack associated with the single IP address. Other stacks which are associated with the single IP address are defined as candidate target stacks and an identification of candidate target stacks and the routing stack is distributed to the stacks. The routing stack is notified when an application associated with a candidate target stack listens to a port of the IP address to establish a current actual target stack. A request to establish a connection to the IP address and the port of the IP address is received and a routing table entry corresponding to the current actual target stack is created to provide a routing path from the routing stack to the current actual target stack.

Abstract: Methods, systems and computer program products according to embodiments of the present invention provide distributing workload between a plurality of data processing systems in a cluster of data processing systems, wherein each of the plurality of data processing systems is executing an instance of an application which communicates over a network such that a connection request to the application may be distributed to any one of the plurality of data processing systems. Such workload distribution may be provided by defining a subset of the plurality of data processing systems which are to receive connection requests to the application having at least one predefined characteristic. A request for a connection to the application is received over the network and it is determined if the request has a characteristic corresponding to the characteristic associated with the subset of the plurality of data processing systems.

Abstract: A value-based caching system and method. A value based cache method can include partitioning a cache into different value-based partitions. Data to be stored in the cache can be valued and the valued data can be cached in individual ones of the value-based partitions. Subsequently, cache entries can be evicted from the value-based partitions. Finally, the caching and evicting can be managed according to the valuing step. In this regard, the cache and eviction management step can ensure greater cache responsiveness for data having a greater value relative to other valued data.

Abstract: Methods, systems and computer program products provide for recovery from a failure of a primary routing communication protocol stack which routes communications over connections to a virtual Internet Protocol address (VIPA) and at least one port associated with the VIPA to a plurality of other communication protocol stacks associated by the primary routing stack and with the VIPA and the at least one port. At least one backup routing communication protocol stack is identified. The backup routing stack stores an identification of stacks associated with the VIPA and the at least one port as candidate target stacks. Messages are received at the backup routing stack identifying stacks having application instances bound to the VIPA and listening on the at least one port as current actual target stacks.

Abstract: A value-based caching system and method. A value based cache method can include partitioning a cache into different value-based partitions. Data to be stored in the cache can be valued and the valued data can be cached in individual ones of the value-based partitions. Subsequently, cache entries can be evicted from the value-based partitions. Finally, the caching and evicting can be managed according to the valuing step. In this regard, the cache and eviction management step can ensure greater cache responsiveness for data having a greater value relative to other valued data.

Abstract: A data re-direction method can include receiving a data re-direction request from an application server; identifying from the data re-direction request at least one data re-direction primitive, the primitive including at least one data element selected from the group consisting of a client identity and a client type; retrieving personalized data according to subsequent client data requests associated with the at least one data re-direction primitive; and, forwarding the retrieved personalized data directly to a POC corresponding to the client data requests without first passing the retrieved personalized data through the application server.

Abstract: Methods, systems, and computer program products for dynamically modifying an application program's behavior in response to changing environmental conditions (such as network changes, system changes, and so forth). The application may solicit such information, and/or may receive unsolicited environmental change notifications. In response to a change notification, the application may take one or more of the following approaches to adapt to the changing conditions: (1) alter its execution; (2) modify its use of, or control of, other cooperating application; and (3) modify the selection of application execution threads. (An application might also decide to make no changes in its behavior.

Abstract: An improved technique is disclosed for routing data across multiple topology subnets, and for improving the connectivity between nodes in multiple topology subnets, by using a common connection network. A new type of virtual node, referred to herein as a “global” virtual routing node or “GVRN”, is defined to represent connectivity to an underlying network that may extend beyond the boundaries of the topology subnets in the end-to-end path. This underlying network is also referred to as a “common connection network” or a “global connection network”. The present invention also defines novel techniques with which border nodes pass routing information between networks to convey connectivity to the GVRN. In many cases, use of GVRNs will result in shorter end-to-end data transmission paths.

Abstract: Methods, systems and computer program products provide assignment of ports for connections originated by multiple application instances executing on different data processing systems utilizing a common network address. An indication of available ports for the common network address is provided to each of the different data processing systems executing the multiple application instances. A port identified as available is selected as a port for a connection utilizing the common network address.

Abstract: Methods, systems and computer program products provide for establishing a connection originated by an application executing on a data processing system in a cluster of data processing systems. A dynamic network address is associated with the application at the data processing system on which the application is executing. If a request is received for the data processing system to originate a connection that is associated with the application, the connection is established utilizing the dynamic network address associated with the application as a source address for the connection.

Abstract: Methods, systems and computer program products are provided for distributing Transport Control Protocol (TCP) connections to a specific data processing system in a cluster of data processing systems by establishing a TCP connection between a client and a first data processing system in the cluster of data processing systems. The information is obtained from the client over the TCP connection to the first data processing system. The information obtained over the TCP connection to the first data processing system is evaluated to select a target data processing system in the cluster of data processing systems for the TCP connection. The TCP connection is transferred from the first data processing system to the selected target data processing system. The transfer of the TCP connection is transparent to the client.

Abstract: Systems, methods and computer program products are provided for preserving a session between an SNA application and a TN3270E server after loss of an IP network connection between the TN3270E server and a TN3270E client that is communicating with the SNA application via the SNA session.

Abstract: Methods, systems and computer program products are provided for providing transactional quality of service providing transaction service level information from an application requesting a data transmission transaction to a communication process executing on a data processing system. The transaction service level information is provided separate from the data for the data transmission transaction. A quality of service level associated with the data transmission transaction is determined based on the transaction service level information received from the application. Other embodiments also provide for establishing a quality of service level without reference to transaction data content while further embodiments provide for establishing a quality of service level for responses.