摘要:
The reassembly timer in a TCP/IP receiver is dynamically set to avoid data corruption on fast networks caused by IP identification wrap-around. A sender generates IP packets with a special option specifying a reassembly time for fragments based on the subnet of the destination or on the calculated round-trip time of the connection. A receiver sets the reassembly timer to the reassembly time specified in the option. A sender can generate IP packets with an alternative option setting a time stamp for the generated packet. A receiver calculates a traversal time based on the difference between the arrival time of the fragment and this time stamp, and sets the reassembly timer based on this traversal time.
摘要:
The reassembly timer in a TCP/IP receiver is dynamically set to avoid data corruption on fast networks caused by IP identification wrap-around. A sender generates IP packets with a special option specifying a reassembly time for fragments based on the subnet of the destination or on the calculated round-trip time of the connection. A receiver sets the reassembly timer to the reassembly time specified in the option. A sender can generate IP packets with an alternative option setting a time stamp for the generated packet. A receiver calculates a traversal time based on the difference between the arrival time of the fragment and this time stamp, and sets the reassembly timer based on this traversal time. A receiver can independently set the reassembly timer to a first reassembly time set by the user for fast networks or to a second reassembly timer set by the user for slow networks based on whether the receiver and sender are on the same subnet.
摘要:
The reassembly timer in a TCP/IP receiver is dynamically set to avoid data corruption on fast networks caused by IP identification wrap-around. A sender generates IP packets with a special option specifying a reassembly time for fragments based on the subnet of the destination or on the calculated round-trip time of the connection. A receiver sets the reassembly timer to the reassembly time specified in the option. A sender can generate IP packets with an alternative option setting a time stamp for the generated packet. A receiver calculates a traversal time based on the difference between the arrival time of the fragment and this time stamp, and sets the reassembly timer based on this traversal time. A receiver can independently set the reassembly timer to a first reassembly time set by the user for fast networks or to a second reassembly timer set by the user for slow networks based on whether the receiver and sender are on the same subnet.
摘要:
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.
摘要:
A receiving host in a TCP/IP network sends an acknowledgment indicating a received data packet is corrupt. The sending host will begin transmitting with a new field set in the IP header called a check-TCP-checksum bit, thereby requesting that all routers in the TCP/IP network perform a checksum on the entire received packet. Routers in the TCP/IP network will perform a complete checksum on an entire packet with the check-TCP-checksum bit set, and not just on the IP header. The routers continuously monitor the ratio of corrupt packets received on a particular port that fail the entire packet checksum to the total number of packets received on that port. If the ratio of corrupt-to-received packets exceeds a corruption threshold, the router assumes that the associated link is causing data corruption and issues a routing update indicating that the link is bad and should be avoided. Once the retransmission rate between the sender and receiver drops below a threshold level, the bad link has been detected and avoided within the TCP/IP network and the check-TCP-checksum option in the IP header is no longer set in data packets transmitted to the receiver host.
摘要:
The present invention provides a method and apparatus for multicast tunneling for mobile devices. The method comprises receiving a multicast packet directed to a plurality of mobile nodes, the mobile nodes being associated with a home subnet and identifying if any of the plurality of the mobile nodes are coupled to a subnet other than the home subnet, wherein each of the identified mobile nodes has an associated transmission path through which that mobile node can be reached. The method further provides that in response to determining that at least some of the mobile nodes are coupled to the subnet other than the home subnet, determining which of the identified mobile nodes has a common next hop in their associated transmission path and generating a packet including at least a portion of the multicast packet and including in the packet a list of mobile nodes that have the common next hop. The method further provides for transmitting the generated packet to the common next hop.
摘要:
A method in a data processing system for reducing the learning curve of a transmission control protocol connection. A domain name system is queried for information. The information and a previously used transmission control protocol parameter for a transmission control protocol connection are received from the domain name system. The information and the previously used transmission control protocol parameter are used to configure a current transmission control protocol connection.
摘要:
A method for virtual segmentation off-load in a logically partitioned data processing system is provided. A data transmission protocol stack formats a data message for segmentation off-load to form a virtual segmentation off-load package. The size of the data message is larger than a size of a maximum transmission unit. A partition manager firmware copies the virtual segmentation off-load package from a first logical partition to a virtual Ethernet adapter associated with a second logical partition. The virtual segmentation off-load package is copied without performing a segmentation operation on the data message associated with the virtual segmentation off-load package.
摘要:
A method, system and apparatus for improving data transfer rate over a network are provided. When a piece of data is to be transmitted to a target system, it is divided into a number of packets and a determination is made as to whether the number of packets exceeds a threshold number. If so, the packets are transferred in parallel over a plurality of network connections. The ideal network connections are TCP/IP connections. Thus, each packet has an IP header, which contains an IP identification field. An indicium is placed into the IP identification field for proper reconstruction of the data by the target system.
摘要:
Responsive to detecting a need for a mobile device to transfer out of a first network, requests are sent from the mobile device to a communication endpoint in mSCTP. The first request is to stop transmissions to a first address of said mobile device. The second request is to add an intermediary address of a mobility support service designated for receiving any communications already in transmission when the first request is sent. The communication link for the mobile device is then transitioned from the current address at the first network to a second address at a second network. The first network and the second network are non-intersecting networks. The mobile device then indicates to the mobility support service that the handover from the first network to the second network is complete. The mobility support service responds to the completion by sending a third request in mSCTP to the communication endpoint to continue communication with the mobile client at the second address.