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How is RTT calculated

0

i would like to know how wireshark is calculating rtt? is it cosidering delayed ack's, piggybacked acks and retransmitted packets.If it is not considered how do i incoorporate/filter these in calcuting rtt

asked 07 Jun '13, 00:49

SThomas's gravatar image

SThomas
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converted 07 Jun '13, 01:48

grahamb's gravatar image

grahamb ♦
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2 Answers:

1

The Wireshark initial Round Trip Time (iRTT) value is calculated when the first two packets of a TCP handshake are seen {SYN, SYN/ACK}. This value will remain the same for the entire TCP conversation. {tcp.analysis.initial_rtt}

When you graph RTT in an IO graph, latency times are depicted between a data packet and the subsequent acknowledgment packet.

You can always do your own handshake analysis and filter on {tcp.flags.syn==1} to find the start of the conversation and then set time deltas to calculate individual session RTTs.

answered 08 Nov '16, 09:57

BruteForce's gravatar image

BruteForce
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accept rate: 9%

0

It takes the send time (ack) - send time (packet, that is, tcp)

k?

answered 07 Nov '16, 09:58

Josh123456789's gravatar image

Josh123456789
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