TCPIP has a mathematical pattern to the
Sequence and ACK numbers. With these numbers and some simple math you can
figure out if you missed, packets, how big the data was, and if there are
duplicate packets.
-----Original Message-----
From: ethereal-users-bounces@xxxxxxxxxxxx
[mailto:ethereal-users-bounces@xxxxxxxxxxxx] On
Behalf Of Kalke, Catherine
Sent: Thursday, March 25, 2004
11:34 AM
To: ethereal-users@xxxxxxxxxxxx
Subject: [Ethereal-users] FW:
packet loss calculation
Would you be able to give
me some information on how the Ethereal trace counts lost packets that are
reported in the summary of a trace? Appreciate your assistance with
this.
Catherine Kalke
Systems Engineering - Technology
Development Group
AT&T Wireless Services
work: + 1 425 580-6177
email: catherine.kalke@xxxxxxxxx
From: Boeve,
Tim
Sent: Thursday, March 25, 2004
11:32 AM
To: Kalke, Catherine
Subject: RE: packet loss
calculation
No, but this is a good
question for the Ethereal mailing list [ethereal-users@xxxxxxxxxxxx] to see if
someone can point you to an answer.
Tim Boeve
From: Kalke,
Catherine
Sent: Thursday, March 25, 2004
11:29 AM
To: Boeve, Tim
Subject: packet loss calculation
Tim,
We are working on the automation of
the BAT testing tools which will allow automated test execution and data
collection. I have identified a list of raw testing data to capture for each
test run to allow us to get more testing data to characterize application and
network performance. One item on the list is packet loss %. If we use Ethereal
as the source to calculate this, then could packet loss include the count of TCP
segment retransmission / total data sent? When I look at the Ethereal trace, I
see a number of retransmissions but when I look at the trace summary, I see 0
packets lost. Do you know how Ethereal counts packets lost?
Catherine Kalke
Systems Engineering - Technology Development
Group
AT&T Wireless Services
work: + 1 425 580-6177
email: catherine.kalke@xxxxxxxxx