摘要:
Approaches are disclosed for switching transport protocol connection keys. A first node sends a keychange request message to a second node, causing the second node to accept subsequent messages digitally signed with a first or second key. The second node sends an acknowledgment message to the first node, causing the first node to accept subsequent messages digitally signed with the first or second key. The first node receives a new message digitally signed with the second key from the second node and determines that there are no remaining messages to be received digitally signed with the first key. In response thereto, the first node only accepts messages digitally signed with the second key and sends a message signed with the second key to the second node, causing the second node to only accept messages digitally signed with the second key.
摘要:
Approaches are disclosed for switching transport protocol connection keys. In a transport protocol module configured to use a first key for signing messages associated with a transport protocol connection, a second key is configured for the transport protocol connection. A first message that is associated with the transport protocol connection is received. The first message includes a first signature. A first and a second message digests are computed for the first message, where the first message digest is based on the first key and the second message digest is based on the second key. The first message is validated if the first signature in the first message matches any one of the first message digest and the second message digest.
摘要:
A system and method supporting synchronization of replicated transport layer connections in a redundant processor telecommunications network element. One method involves receiving, at a network element comprising an active transport protocol process coupled to a standby transport protocol process, information identifying a newly created transport layer connection maintained at the active transport protocol process; assigning a unique connection identifier to the transport layer connection; sending the unique connection identifier, in association with other, protocol-specific connection identifying information, to the standby protocol process; and sending, to the standby transport protocol process, one or more messages comprising one or more properties or statistics associated with the transport layer connection, wherein the messages identify the transport layer connection using the unique connection identifier.
摘要:
A method is disclosed for rapidly detecting a protocol failure. In one embodiment, the method includes receiving an indication that a first process has failed. The first process having been engaged in communications over one or more network connections with a second process. A packet is formed, such that the packet appears to have been formed by the first process. The packet includes one or more data values, which, when received and processed by the second process, will cause the second process to close the network connection. The packet is sent to the second process. When the second process receives the packet, the second process to closes the network connection.
摘要:
A method detects a change in TCP receive window size while preventing fragmentation of data. A TCP stack receives a segment that advertises a receive window size of zero. If data needs to be sent, and only if so, a timer is started. When the timer expires, a TCP segment that contains a first sequence number value equal to second sequence number representing sent but unacknowledged data minus one, and a segment length value of zero, is sent. Without sending a fragment of data, this triggers a peer TCP process to send an updated window size. A TCP ACK segment is received and contains an updated receive window size. If the updated receive window size is greater than a specified value, then the data is sent. Otherwise, a counter is incremented, and the steps are re-performed if the counter is less than a specified value.
摘要:
A system and method supporting efficient, scalable stateful switchover of transport layer connections in a telecommunications network element. One method involves receiving, at a network element comprising an active transport protocol process coupled to a standby protocol process, a request to configure a first transport layer connection maintained at the active transport protocol process for stateful switchover; receiving an event associated with the first transport layer connection; creating a message containing replicated event information based on the received event; sending the message to the standby transport protocol process; and processing the message at the standby transport protocol process, wherein the standby transport protocol process replicates state information for the first connection.
摘要:
A method for detecting unavailable network connections comprises, at a first data processing node that is hosting a transport protocol connection that uses a plurality of sequence values to identify messages sent to a peer node, wherein the first node is communicatively coupled to a second data processing node serving as a redundant backup, periodically sending a checkpoint sequence value to the second node; detecting that either the transport protocol connection or a process using the transport protocol connection is unavailable, without use of a timeout; and in response thereto, sending a notification to the peer node, wherein the notification includes the checkpoint sequence value. One embodiment provides for rapidly detecting and responding to failure of a TCP process without using long timeouts as conventionally provided in long-lived applications that run on top of TCP.
摘要:
A system and method for performing stateful switchover with reduced data, such as only metadata about a TCP window state. The metadata comprises a size of TCP packets used to send BGP messages, and which of those have been acknowledged by a neighbor networking device. The networking device comprises a BGP module to establish a BGP session between the networking device and a neighbor networking device. An active transport module within the networking device synchronizes with a standby transport module within the networking device by sending the metadata. A fault detector within the networking device initiates a stateful switchover from the active transport module to the standby transport module responsive to detecting a failure of a process and/or processor. The standby transport module uses the metadata to determine stateful metadata for preserving current BGP and TCP sessions of the networking device with dummy TCP packets having the same size ad sent TCP packets and containing safe BGP message data.
摘要:
A method detects a change in TCP receive window size while preventing fragmentation of data. A TCP stack receives a segment that advertises a receive window size of zero. If data needs to be sent, and only if so, a timer is started. When the timer expires, a TCP segment that contains a first sequence number value equal to second sequence number representing sent but unacknowledged data minus one, and a segment length value of zero, is sent. Without sending a fragment of data, this triggers a peer TCP process to send an updated window size. A TCP ACK segment is received and contains an updated receive window size. If the updated receive window size is greater than a specified value, then the data is sent. Otherwise, a counter is incremented, and the steps are re-performed if the counter is less than a specified value.
摘要:
A method for improving resistance of network protocols running on transmission control protocol (TCP), such as BGP. For example, a method comprises receiving, from a TCP application, a request to ignore all TCP segments with an RST bit set, except for solicited RST segments; establishing a filter that blocks all but solicited TCP RST segments; receiving a TCP segment with a SYN bit set and a sequence number value within an allowed window for a TCP connection matching the received segment, and for a session of the TCP application; re-configuring the filter to allow TCP RST segments for the connection associated with the received segment; requesting the TCP application to initiate an event that will induce a legitimate sender of the received segment to send a valid TCP RST segment in response; and closing the connection only when a TCP RST segment is received in response.