Abstract: The present invention provides a method and apparatus for providing fragmentation at a transport level along a transmission path. The method comprises receiving a data packet from a first remote device for transmission to a second remote device, wherein the data packet includes a transport-level protocol packet encapsulated in a network-level protocol packet and determining if a size of the received data packet is greater than a maximum transmission unit (MTU) value. The method further comprises performing fragmentation of the data packet at a transport-level protocol into two or more fragments in response to determining that the size of the received data packet is greater than the MTU value and transmitting one or more of the fragments to the second remote device.

Abstract: In one embodiment, an operating system manages virtualized instances of hardware resources and migration enabled applications partitioned into one of multiple partitions with a separate operating system kernel running in each of the partitions. A migration event controller of the operating system manages the checkpoint and restart process during migration of a virtualized instance of at least one migration enabled application from a departure partition to an arrival partition. The migration event controller supports migration enabled applications to separately specify at least one application specific checkpoint script and restart script to be triggered by checkpoint and restart events by the migration event controller so the at least one migration enabled application can participate in performing the checkpoint and restart process for additional state information during migration of the virtualized instance from the departure partition to the arrival partition.

Abstract: An apparatus and method for an improved bulk read socket call are provided. With the apparatus and method, a new field, so_rcvlen, is added to the socket structure that identifies the bulk read size requested by the user. The kernel of the prior art recv( ) function is also modified so that it sets the so_rcvlen to the size requested by the user prior to the recv( ) function going to sleep and waiting for the full data size requested by the user. A new flag, SP_MSGWAITALL, is also provided in the socket structure. In the TCP input processing, when data is received for a particular socket, the current setting of the SP_MSGWAITALL is checked. If the SP_MSGWAITALL flag is set, it is determined whether the amount of data stored in the socket receive buffer is less than the value of so_rcvlen. If not, the TCP input processing does not wake up the recv( ) thread. However, for every alternate segment, the TCP input processing sends back an acknowledgment (ACK).

Abstract: An apparatus and computer-readable medium for securely maintaining communications network connection data is disclosed. According to one embodiment, an apparatus is disclosed according to which a user is prompted for network element address substitution data which specifies a substitute network element address for a network element address associated with a network element of a first communications network. The network element address substitution data is then stored within a first storage element, wherein access to the first storage element outside of the first communications network is restricted. Connection monitor data associated with the first communications network is processed utilizing the network element address substitution data.

Abstract: Methods, systems, and products are provided for tunneling IPv6 packets. Embodiments include receiving, by an origin IPv6 border router from an origin IPv6 host, an IPv6 packet having an IPv6 destination address; receiving, by an origin IPv6 border router from an origin IPv6 host, an IPv4 address for a destination IPv6 border router retrieved from a data structure associating IPv6 destination addresses with IPv4 addresses for destination IPv6 border routers; encapsulating, by the origin IPv6 border router, the IPv6 packet in an IPv4 packet; and sending the encapsulated packet to a destination IPv6 border router at the IPv4 address. In many embodiments, encapsulating, by the origin IPv6 border router, the IPv6 packet in an IPv4 packet is carried out by adding an IPv4 header to the IPv6 packet.

Abstract: A method, system and apparatus for improving network performance of a multiprocessor system that has a limited number of physical network interfaces by using virtual IP addresses are provided. When a processor of the multiprocessor system determines that it is processing network data, it uses a virtual IP address to transmit the data. The virtual IP address is associated with a buffer; and thus the data is sent to the buffer. This allows the processor to be free to process other data, network or otherwise. The buffer, with the help of a controller, then contends for the use of one of the limited physical network interfaces to transmit the data.

Abstract: A computer implemented method, data processing system, and computer program product for selectively preserving network state during a checkpoint operation. Packets flowing through a network stack are examined to determine whether the packets belong to a WPAR under checkpoint. If one or more packets belong to a WPAR under checkpoint, a filter is used to block the packets from flowing through the network stack. Address information in each blocked packet is checked against an access list of allowed communications to determine if the access list indicates that a packet is an allowed packet. If the access list indicates that one of the packets is an allowed packet, that packet is unblocked and allowed to continue flowing through the network stack during the checkpoint operation. If the access list indicates that another of the packets is not an allowed packet, that packet is discarded during the checkpoint operation.

Abstract: A computer implemented method, apparatus, and computer program product for managing state data in a workload partitioned environment. Process state data for a process in a workload partition is saved. Process state data is used to restore the process to a given state. State data associated with open sockets and open files bound to the first process is saved. In response to a determination that the process is associated with a domain socket that is bound to a socket file, an absolute pathname for the socket file is saved. A domain socket associated with a connecting process in the workload partition uses the socket file to connect to a domain socket associated with a listening process in the same workload partition to enable the two processes to communicate with each other.

Abstract: A computer implemented method, data processing system, and computer program product for enabling network statistics to be collected per software partition. When an incoming data packet is received at the Internet Protocol (IP) layer of an operating system, the IP address in the incoming data packet is identified. The IP address in the incoming data packet is then compared against IP addresses stored in a hash table, wherein the hash table maps each IP address in the hash table to a software partition of the operating system. If an IP address in the hash table matches the IP address in the data packet, the software partition mapped to the located IP address in the hash table is identified. Network statistics collected for the incoming data packet are then associated with the software partition.

Abstract: A computer implemented method, data processing system, and computer program product for enabling the restoration of in-flight file descriptors during a checkpoint operation. Responsive to a checkpoint operation being initiated on a process in a workload partition, in-flight file pointers in an in-flight file queue on a socket bound to the process are identified. A file descriptor is instantiated in the process file table of the process for each identified in-flight file pointer in the in-flight file queue. After completion of the checkpoint operation, the in-flight file queue on the socket may be reconstructed in a restore operation using the instantiated file descriptors.

Abstract: Methods, systems, and products are provided for tunneling IPv6 packets. Embodiments include receiving, by an origin IPv6 border router from an origin IPv6 host, an IPv6 packet having an IPv6 destination address; receiving, by an origin IPv6 border router from an origin IPv6 host, an IPv4 address for a destination IPv6 border router retrieved from a data structure associating IPv6 destination addresses with IPv4 addresses for destination IPv6 border routers; encapsulating, by the origin IPv6 border router, the IPv6 packet in an IPv4 packet; and sending the encapsulated packet to a destination IPv6 border router at the IPv4 address. In many embodiments, encapsulating, by the origin IPv6 border router, the IPv6 packet in an IPv4 packet is carried out by adding an IPv4 header to the IPv6 packet.

Abstract: In a first aspect, a first method is provided for creating a media access control (MAC) address for a device. The first method includes the steps of (1) obtaining one or more identifiers; (2) obtaining a first MAC address; and (3) creating at least a second MAC address based on the one or more identifiers and the first MAC address. Numerous other aspects are provided.

Abstract: A data processing system for resending a previously sent email message. A new recipient for the previously sent email message is selected. The new recipient of the previously sent email message is added in response to selecting the new recipient, wherein the previously sent email message is directed to the new recipient and a previous recipient. An indicator to the previously sent email message is added in response to selecting the new recipient, wherein the indicator indicates that the new recipient has been added to a form a new version of the previously sent email message. The new version of the previously sent email message is sent in response to adding the indicator, wherein the indicator causes the new version of the previously sent email message to replace the previously sent email message at an email program of the previous recipient.

Abstract: A method, data processing system, and computer usable code are provided for protocol definition for software bridge failover. In a first aspect of the present invention, a first software bridge determines the proper working operation of a physical adapter. Limbo packets are sent to a second software bridge alerting the second software bridge that the first software bridge is no longer bridging traffic responsive to the physical adapter failure in the first software bridge. The second software bridge receives the limbo packets, and, in response to receiving the limbo packets, asserts primary control and initiates bridging of traffic. In an alternative aspect of the present invention a first software bridge sends keep-alive packets. A second software bridge monitors the keep-alive packets from the first software bridge and, in response to a failure to detect the keep-alive packets from the first software bridge, the second software bridge initiates bridging of traffic.

Abstract: A system and method to manage device access in a software partition are provided. The illustrative embodiments provide a mechanism for exporting resources/devices from an administrator partition to a software partition in its purview. A trusted device list data structure is provided that identifies which devices are permitted to be exported into a software partition from an administrative partition. This trusted device list data structure also identifies which of the devices in the list of devices should be exported by default when exporting devices to a software partition, i.e. if no overrides are specified. In addition, a user-specifiable mechanism to override the entries in the trusted device list data structure is provided. For security purposes, this mechanism may not be used to export devices not listed in the trusted device list data structure. The mechanism may also be used to prevent the exporting of devices which are exported by default.

Abstract: In a method comprising an embodiment of the invention, an original application initially binds to a port, and selects or designates a confidential key, which usefully may be a conventional cookie. The invention also sets a socket option, referred to by way of example, as SO_SECURE_REUSEPORT. The confidential key, together with the port number, is then registered with the operating system of a host associated with the port. In order for another application to subsequently bind to the port, such application must provide the operating system with a key that is identical to the confidential key. In one useful embodiment of the invention, a first application binds a socket to a particular port associated with the host. A specified key is registered with the operating system, and a second application is allowed to bind to the particular port only if the second application can furnish the operating system with a key that matches the specified key.

Abstract: A data processing system for resending a previously sent email message. A new recipient for the previously sent email message is selected. The new recipient of the previously sent email message is added in response to selecting the new recipient, wherein the previously sent email message is directed to the new recipient and a previous recipient. An indicator to the previously sent email message is added in response to selecting the new recipient, wherein the indicator indicates that the new recipient has been added to a form a new version of the previously sent email message. The new version of the previously sent email message is sent in response to adding the indicator, wherein the indicator causes the new version of the previously sent email message to replace the previously sent email message at an email program of the previous recipient.

Abstract: A graphic user interface of a network client (106) includes a stock ticker from a stock server (110) and a news sidebar from a news server (112) over the IP addresses advertised to the client (106) in its list of multi-homed addresses from the video server (104) specified under Stream Control Transmission Protocol (SCTP). The client accepts real-time data from the stock exchange server and the news agency server on the multi-homed IP addresses designated in the association with the video server (104) without knowing that the data is coming from a different source than the video server (104). The real-time data feeds from the video, stock and news servers are aggregated on the client (106) with enhanced speed because the feeds come directly to the client and not via the video server.

Abstract: TCP congestion avoidance is implemented upon retransmission of a packet and is reverted back to the original congestion state upon receipt of an early acknowledgement (ACK), indicating reordering of packets, thereby eliminating a needless restriction on TCP bandwidth. Upon receiving an ACK to a retransmitted packet, it is determined if the ACK resulted from receipt of the original reordered packet or the retransmitted packet, based on the arrival time of the ACK at the sender. If the round-trip-time (RTT) for the retransmitted packet is much lower than the average or current calculated RTT for the network link between sender and receiver, then the retransmission occurred as a result of a reordering event, and the congestion window is restored back to its value prior to the retransmission, thereby permitting the network link to continue operating at its original increased throughput.

Abstract: A method, system and computer program product for transitioning network traffic between logical partitions in one or more data processing systems are disclosed. The method includes defining a plurality of logical partitions with respect to one or more processing units of one or more data processing systems and dynamically reallocating resources from a second partition to a first partition among the plurality of logical partitions. Packets awaiting processing are transferred from the second partition to the first partition and processed on the first partition.