摘要:
Approaches for preventing TCP data injection attacks in packet-switched networks are disclosed. An ACK message or dummy segment is sent to verify the authenticity of the data in the re-assembly buffer, and to help discard spurious data faster. These approaches involve the sender in detection of spurious data, and make improved use of mechanisms for processing ACK messages that are native to typical TCP implementations. The latter approach may be implemented without modification of the sender's TCP implementation. Further, the receiver's TCP implementation maintains compatibility with RFC 793.
摘要:
Approaches for preventing TCP data injection attacks in packet-switched networks are disclosed. A first approach provides for dropping received segments that carry ACK values smaller than the next unacknowledged sequence number expected minus the maximum window size. This approach helps keep spurious injected segments out of the TCP re-assembly buffer. In a second approach, heuristics are used to examine the sequence number of a newly arrived segment, and when the sequence number is the next expected, then the newly arrived segment is used and the contents of the re-assembly buffer are not considered. Further, if the data payload of the newly arrived segment overlaps in sequential order with segments already in the re-assembly buffer, the overlapped segments in the re-assembly buffer are considered spurious and are discarded. Thus, this approach helps remove spurious data from the re-assembly buffer if the first approach somehow fails to prevent the data from entering the re-assembly buffer.
摘要:
In one embodiment, a method includes determining a first template defining a data format for one or more first data records and a second template defining a data format for one or more second data records. The template may be needed to decode the information included in an associated data record. The first template is sent on a first stream of a multi-stream protocol in an ordered fashion, such as SCTP. The one or more first data records are also sent on the first stream in an ordered fashion and include first flow information for data sent through a network device. A second template is sent on a second stream using the multi-stream protocol in an ordered fashion. One or more second data records are sent on the second stream including second flow information for data sent through the network device.
摘要:
Rules in NAT and firewall devices are updated only when a packet flow is verified as genuine through transport-layer message acknowledgment sequences. When a device receives a packet indicating initiation of a new association, the device stores an internal source tag, an internal destination tag, an external source tag, and an external destination tag. Only after receiving a completion acknowledgment message from the destination node, the device sets the internal source tag equal to the external source tag, and sets the internal destination tag equal to the external destination tag. The rules are then updated based on the internal tags. As a result, the approach thwarts denial of service (DOS) attacks that seek to modify rules of NAT and firewall devices to permit harmful traffic.
摘要:
In one embodiment, a method can include: (i) pre-configuring a stream control transmission protocol (SCTP) association; (ii) receiving a transmission control protocol (TCP) packet in a network device, where the TCP packet is intended for a destination node; (iii) encapsulating the TCP packet into an SCTP payload; and (iv) transmitting the SCTP payload across a wide area network (WAN).
摘要:
In one embodiment, a method can include: (i) pre-configuring a stream control transmission protocol (SCTP) association; (ii) receiving a transmission control protocol (TCP) packet in a network device, where the TCP packet is intended for a destination node; (iii) encapsulating the TCP packet into an SCTP payload; and (iv) transmitting the SCTP payload across a wide area network (WAN).
摘要:
A method and apparatus is disclosed for transport level server advertisement and discovery. First information is received at a transport protocol stack. The transport protocol stack recognizes that the first information represents one or more services provided by a server. Based on the first information, the transport protocol stack determines whether to use any of the one or more services.
摘要:
Methods and apparatus for supporting mobility using SCTP are disclosed. In accordance with one aspect of the invention, an SCTP association between a first network device and a second network device may be modified. The SCTP association includes a first set of IP addresses associated with the first network device and a second set of IP addresses associated with the second network device. The first network device establishes the SCTP association between the first network device and the second network device. An SCTP configuration message is then sent from the first network device to the second network device, the configuration message indicating a modification to be made to the SCTP association, thereby enabling the SCTP association to be modified without disconnecting an existing session.
摘要:
A method is disclosed for sharing a transport connection in a host having two or more processors that exchange limited inter-processor communications. Ranges of transport sequence numbers are assigned to the processors of the host, and a range assigned to a particular processor does not overlap with any other range assigned to any other processor. An outbound message is sent over the transport connection from a processor of the host, where the message includes a transport sequence number selected from the range assigned to that processor. An inbound message is received at a designated processor of the host that is configured to receive all inbound messages sent to the host over the transport connection.
摘要:
A method is disclosed for providing fault tolerance of an application over a Stream Control Transmission Protocol (SCTP) connection. A method for moving a transport connection from a first host to a second host on a network is also described. After establishing a transport connection between the first host and a peer host, first information about the transport connection is transferred to the second host. Upon the first host becoming unavailable, the second host sends to the peer host a request to update the state of the transport connection. The peer host then updates the transport connection. Without resetting the transport connection, the second host then establishes the same transport connection with the peer host.