System and method for conveying the reason for TCP reset in machine-readable form
View Patent ↗An RST reason code is conveyed in a predetermined field of the TCP or IP header for a TCP RST packet in order to indicate the reason for the RST. In this way, an enhanced TCP device that receives the RST packet can access the RST reason code in machine-readable form and, unlike prior art implementations in which ASCII text is carried in the TCP payload to provide a RST reason, without having to process the payload of the TCP packet.
1. A method for conveying the reason for TCP reset in machine-readable form, the method comprising:
by a transmitting device, formatting a message including a TCP RST segment and a RST reason code in a header field of the message and transmitting the message over a communication network, the RST reason code indicating a reason for the TCP RST segment; and
by a receiving device, receiving the message from the communication network, retrieving the RST reason code from the header field of the message, and processing the TCP RST segment based on the RST reason code, wherein the header field is a field of a TCP header of the TCP RST segment, and wherein the field of the TCP header is an Urgent Pointer field.
2. A method for conveying the reason for TCP reset in machine-readable form, the method comprising:
by a transmitting device, formatting a message including a TCP RST segment and a RST reason code in a header field of the message and transmitting the message over a communication network, the RST reason code indicating a reason for the TCP RST segment; and
by a receiving device, receiving the message from the communication network, retrieving the RST reason code from the header field of the message, and processing the TCP RST segment based on the RST reason code, wherein the message includes an IP datagram encapsulating the TCP RST segment, and wherein the header field is a field of an IP header of the IP datagram.
3. A method according to claim 2 , wherein IP datagram is an IPv4 datagram, and wherein the field of the IP header is the Identification field of the IPv4 datagram.
4. A method according to claim 2 , wherein IP datagram is an IPv6 datagram, and wherein the field of the IP header is the Flow Label field of the IPv6 datagram.
5. A method according to claim 4 , where the Flow Label is subdivided into a RST reason code sub-field and a flow sub-field.
6. A method for conveying the reason for TCP reset in machine-readable form, the method comprising:
formatting, by a transmitting device, a message including a TCP RST segment and a RST reason code in a header field of the message, the RST reason code indicating a reason for the TCP RST segment; and
transmitting the message by the transmitting device over a communication network, wherein the header field is a field of a TCP header of the TCP RST segment, and wherein the field of the TCP header is an Urgent Pointer field.
7. A method for conveying the reason for TCP reset in machine-readable form, the method comprising:
formatting, by a transmitting device, a message including a TCP RST segment and a RST reason code in a header field of the message, the RST reason code indicating a reason for the TCP RST segment; and
transmitting the message by the transmitting device over a communication network, wherein the message includes an IP datagram encapsulating the TCP RST segment, and wherein the header field is a field of an IP header of the IP datagram.
8. A method according to claim 7 , wherein IP datagram is an IPv4 datagram, and wherein the field of the IP header is the Identification field of the IPv4 datagram.
9. A method according to claim 7 , wherein IP datagram is an IPv6 datagram, and wherein the field of the IP header is the Flow Label field of the IPv6 datagram.
10. A method according to claim 9 , where the Flow Label is subdivided into a RST reason code sub-field and a flow sub-field.
11. Apparatus for conveying the reason for TCP reset in machine-readable form, the apparatus comprising:
a transmitter configured to format a message including a TCP RST segment and a RST reason code in a header field of the message, the RST reason code indicating a reason for the TCP RST segment; and
a network interface in communication with the transmitter and configured to transmit the message over a communication network, wherein the header field is a field of a TCP header of the TCP RST segment, and wherein the field of the TCP header is an Urgent Pointer field.
12. Apparatus according to claim 11 , wherein the transmitter includes dedicated hardware that operates outside the immediate control of a software program, the dedicated hardware configured to at least insert the RST reason code into the header field of the message.
13. Apparatus for conveying the reason for TCP reset in machine-readable form, the apparatus comprising:
a transmitter configured to format a message including a TCP RST segment and a RST reason code in a header field of the message, the RST reason code indicating a reason for the TCP RST segment; and
a network interface in communication with the transmitter and configured to transmit the message over a communication network, wherein the message includes an IP datagram encapsulating the TCP RST segment, and wherein the header field is a field of an IP header of the IP datagram.
14. Apparatus according to claim 13 , wherein IP datagram is an IPv4 datagram, and wherein the field of the IP header is the Identification field of the IPv4 datagram.
15. Apparatus according to claim 13 , wherein IP datagram is an IPv6 datagram, and wherein the field of the IP header is the Flow Label field of the IPv6 datagram.
16. Apparatus according to claim 15 , where the Flow Label is subdivided into a RST reason code sub-field and a flow sub-field.
17. Apparatus according to claim 13 , wherein the transmitter includes dedicated hardware that operates outside the immediate control of a software program, the dedicated hardware configured to at least insert the RST reason code into the header field of the message.
18. A method for processing TCP RST packets, the method comprising:
receiving, by a receiving device over a communication network, a message including a TCP RST segment and a RST reason code in a header field of the message, the RST reason code indicating a reason for the TCP RST segment;
retrieving the RST reason code from the header field of the message; and
processing the TCP RST segment based on the RST reason code, wherein the header field is a field of a TCP header of the TCP RST segment, and wherein the field of the TCP header is an Urgent Pointer field.
19. A method for processing TCP RST packets, the method comprising:
receiving, by a receiving device over a communication network, a message including a TCP RST segment and a RST reason code in a header field of the message, the RST reason code indicating a reason for the TCP RST segment;
retrieving the RST reason code from the header field of the message; and
processing the TCP RST segment based on the RST reason code, wherein the message includes an IP datagram encapsulating the TCP RST segment, and wherein the header field is a field of an IP header of the IP datagram.
20. A method according to claim 19 , wherein IP datagram is an IPv4 datagram, and wherein the field of the IP header is the Identification field of the IPv4 datagram.
21. A method according to claim 19 , wherein IP datagram is an IPv6 datagram, and wherein the field of the IP header is the Flow Label field of the IPv6 datagram.
22. A method according to claim 21 , where the Flow Label is subdivided into a RST reason code sub-field and a flow sub-field.
23. Apparatus for processing TCP RST packets, the apparatus comprising:
a network interface configured to receive a message over a communication network; and
a receiver configured to process the message, and when the message includes a TCP RST segment and a RST reason code in a header field of the message, the RST reason code indicating a reason for the TCP RST segment, to retrieve the RST reason code from the header field of the message and process the TCP RST segment based on the RST reason code, wherein the header field is a field of a TCP header of the TCP RST segment, and wherein the field of the TCP header is an Urgent Pointer field.
24. Apparatus according to claim 23 , wherein IP datagram is an IPv4 datagram, and wherein the field of the IP header is the Identification field of the IPv4 datagram.
25. Apparatus according to claim 23 , wherein the receiver includes dedicated hardware that operates outside the immediate control of a software program, the dedicated hardware configured to retrieve the RST reason code from the header field of the message and process the TCP RST segment based on the RST reason code.
26. Apparatus according to claim 25 , wherein the message includes an IP header and a TCP header, and wherein the dedicated hardware comprises:
an IP header processor configured to process the IP header including at least determining that the message includes a TCP segment; and
a TCP header processor configured to process the TCP header including at least determining that the TCP segment is a TCP RST segment, at least one of the IP header processor and the TCP header processor configured to retrieve the RST reason code from the header field of the message.
27. Apparatus for processing TCP RST packets, the apparatus comprising:
a network interface configured to receive a message over a communication network; and
a receiver configured to process the message, and when the message includes a TCP RST segment and a RST reason code in a header field of the message, the RST reason code indicating a reason for the TCP RST segment, to retrieve the RST reason code from the header field of the message and process the TCP RST segment based on the RST reason code, wherein the message includes an IP datagram encapsulating the TCP RST segment, and wherein the header field is a field of an IP header of the IP datagram.
28. Apparatus according to claim 27 , wherein IP datagram is an IPv6 datagram, and wherein the field of the IP header is the Flow Label field of the IPv6 datagram.
29. Apparatus according to claim 28 , where the Flow Label is subdivided into a RST reason code sub-field and a flow sub-field.
30. Apparatus according to claim 27 , wherein the receiver includes dedicated hardware that operates outside the immediate control of a software program, the dedicated hardware configured to retrieve the RST reason code from the header field of the message and process the TCP RST segment based on the RST reason code.
31. Apparatus according to claim 30 , wherein the message includes an IP header and a TCP header, and wherein the dedicated hardware comprises:
an IP header processor configured to process the IP header including at least determining that the message includes a TCP segment; and
a TCP header processor configured to process the TCP header including at least determining that the TCP segment is a TCP RST segment, at least one of the IP header processor and the TCP header processor configured to retrieve the RST reason code from the header field of the message.