Estimation of web client response time

• US 7,779,133 B2
• Filed: 01/04/2007
• Issued: 08/17/2010
• Est. Priority Date: 01/04/2007
• Status: Expired due to Fees

• Current Assignee: R2 Solutions LLC (Acacia Research Corporation)
• Original Assignee: Yahoo! Inc. (Apollo Global Management, Inc.)
• Inventors: Subramaniam, Subbu
• Primary Examiner(s): Dharia; Rupal D
• Assistant Examiner(s): Tran; Jimmy H
• Application Number:
  US11/619,849
• Publication Number:
  US 20080168177A1
• Time in Patent Office: 1,321 Days
• Field of Search: 709/231, 709/227, 709/228, 709/237, 709/249, 370/431, 370/433, 710/105
• US Class Current: 709/227
• CPC Class Codes: H04L 12/66 Arrangements for connecting between networks having differing types of switching systems, e.g. gateways
• CPC Class Codes: H04L 41/22 comprising specially adapted graphical user interfaces [GUI]
• CPC Class Codes: H04L 41/5003 Managing SLA; Interaction between SLA and QoS
• CPC Class Codes: H04L 41/5019 Ensuring fulfilment of SLA
• CPC Class Codes: H04L 43/0852 Delays
• CPC Class Codes: H04L 43/0864 Round trip delays
• CPC Class Codes: H04L 43/106 using time related information in packets, e.g. by adding timestamps

Abstract

Apparatuses, methods, and systems directed to estimating response time and other performance metrics in network communications. Some embodiments of the invention allow users to monitor and estimate response time in real time. In other particular embodiments, the systems disclosed below can be used to estimate response time using server logs. In some embodiments, the present invention involves using open control blocks as a proxy to estimate the number of dropped connections.

Claims

1. A method comprising:

monitoring communications transmitted in a data stream, the communications comprising communications between a plurality of hosts, each communication comprising one or more Transmission Control Protocol (TCP) packets including one or more of SYN packets, FIN packets, ACK packets, and data packets;

filtering the communications to extract SYN and FIN packets;

detecting a first SYN packet transmitted from a first host to be received by a second host, the first SYN packet operative to initiate a first connection between the first host and the second host;

assigning a first SYN timestamp to the first SYN packet;

detecting a first FIN packet transmitted between the first host and the second host, the first FIN packet operative to terminate at least a first side of the first connection;

assigning a first FIN timestamp to the first FIN packet;

computing a first estimated response time between the first host and the second host, the first estimated response time being the elapsed time between the first SYN timestamp and the first FIN timestamp;

detecting a second FIN packet transmitted between the first host and the second host, the second FIN packet operative to terminate at least a second side of the first connection;

assigning a second FIN timestamp to the second FIN packet; and

adjusting the first estimated response time by the difference between the first FIN timestamp and the second FIN timestamp.

2. The method of claim 1, further comprising:

opening a control block for the first connection upon detecting the first SYN packet.

3. The method of claim 2, further comprising:

dropping the control block after detecting the first FIN packet.

4. The method of claim 1, wherein the control block comprises one or more of a start time, the first SYN timestamp, the first FIN timestamp, one or more counters for a response time, one or more counters for a Round Trip Time, two or more counters for a number of bytes, two or more sequence numbers, and one or more flags for a connection termination packet.

5. The method of claim 1, further comprising:

computing a total number of bytes transmitted between the first and second hosts.

6. The method of claim 1, further comprising:

determining a total number of dropped connections between the plurality of hosts by counting the number of open control blocks at an end of the data stream.

7. The method of claim 1, wherein the data stream comprises one or more logs, wherein a log comprises one or more entries, each entry comprising a source address and a port number, a destination address and a port number, one or more flags, one or more data sequence numbers, and one or more options.

8. The method of claim 1, wherein the monitoring, filtering, detecting the first SYN packet, assigning the first SYN timestamp, detecting the first FIN packet, assigning the first FIN timestamp, and computing the first estimated response time are performed in real time.

9. Logic encoded in one or more computer-readable non-transitory storage media for execution on a data processing system, wherein the logic when executed is operable to:

monitor communications transmitted in a data stream, the communications comprising communications between a plurality of hosts, each communication comprising one or more Transmission Control Protocol (TCP) packets including one or more of SYN packets, FIN packets, ACK packets, and data packets;

filter the communications to extract SYN and FIN packets;

detect a first SYN packet transmitted from a first host to be received by a second host, the first SYN packet operative to initiate a first connection between the first host and the second host;

assign a first SYN timestamp to the first SYN packet;

detect a first FIN packet transmitted between the first host and the second host, the first FIN packet operative to terminate at least a first side of the first connection;

assign a first FIN timestamp to the first FIN packet;

compute a first estimated response time between the first host and the second host, the first estimated response time being the elapsed time between the first SYN timestamp and the first FIN timestamp;

detect a second FIN packet transmitted between the first host and the second host, the second FIN packet operative to terminate at least a second side of the first connection;

assign a second FIN timestamp to the second FIN packet; and

adjust the first estimated response time by the difference between the first FIN timestamp and the second FIN timestamp.

10. The logic of claim 9, further operable to:

open a control block for the first connection upon detection of the first SYN packet.

11. The logic of claim 10, further operable to:

drop the control block for the first connection after detection of the first FIN packet.

12. The logic of claim 9, wherein the control block comprises one or more of a start time, the first SYN timestamp, the first FIN timestamp, one or more counters for a response time, one or more counters for a Round Trip Time, two or more counters for a number of bytes, two or more sequence numbers, and one or more flags for a connection termination packet.

13. The logic of claim 9, further operable to:

compute a total number of bytes transmitted between the first and second hosts.

14. The logic of claim 9, further operable to:

determine a total number of dropped connections between the plurality of hosts by counting the number of open control blocks at an end of the data stream.

15. The logic of claim 9, wherein the data stream comprises one or more logs, wherein a log comprises one or more entries, each entry comprising a source address and a port number, a destination address and a port number, one or more flags, one or more data sequence numbers, and one or more options.

16. The logic of claim 9, wherein the logic operable to monitor, filter, detect the first SYN packet, assign the first SYN timestamp, detect the first FIN packet, assign the first FIN timestamp, and compute the first estimated response time is operable to monitor, filter, detect the first SYN packet, assign the first SYN timestamp, detect the first FIN packet, assign the first FIN timestamp, and compute the first estimated response time in real time.

17. A method comprising:

receiving a first Transmission Control Protocol (TCP) packet;

assigning a first timestamp to the first TCP packet;

determining if the first TCP packet corresponds to an existing control block;

if the first TCP packet does not correspond to an existing control block,

determining if the first TCP packet is a SYN packet;

if the first TCP packet is a SYN packet,

creating a first control block corresponding to a first connection between a first host and a second host, the first control block comprising the first timestamp;

if the first TCP packet corresponds to an existing first control block corresponding to the first connection between the first host and the second host,

determining if the first TCP packet is a SYN packet corresponding to the first connection;

if the first TCP packet is a SYN packet corresponding to the first connection,

determining if a SYN-ACK packet has been received for the first connection;

if the SYN-ACK packet has not been received for the first connection,

replacing a client start sequence number in the first control block with a sequence number in the SYN packet;

if the SYN-ACK packet has been received for the first connection,

replacing a client start sequence number in the first control block with a sequence number in the SYN packet; and

resetting a start time in the first control block with the first timestamp;

if the first TCP packet is not a SYN packet corresponding to the first connection;

determining if the first TCP packet is a first FIN packet corresponding to the first connection;

if the first TCP packet is a first FIN packet corresponding to the first connection,

computing an estimated response time for the first connection, the estimated response time being the difference in time between the first timestamp and the start time in the first control block;

determining if the first TCP packet is a second FIN packet corresponding to the first connection;

if the first TCP packet is a second FIN packet corresponding to the first connection,

adjusting the estimated response time for the first connection by the difference between the first timestamp assigned to the first FIN packet and the first time stamp assigned to the second FIN packet.

18. The method of claim 17, further comprising:

if the first TCP packet corresponds to an existing first control block corresponding to the first connection between the first host and the second host, and if the first TCP packet is not a SYN packet corresponding to the first connection;

determining if the first TCP packet is a SYN-ACK packet;

if the first TCP packet is a SYN-ACK packet,

computing a round trip time, the round trip time being the difference in time between a start time in the first control block and the first timestamp;

if the first TCP packet is not a SYN-ACK packet,

determining if the first TCP packet is a reset (RST) packet;

if the first TCP packet is an RST packet,

 

dropping the first control block.