I'm not sure I completely understood the requirement but try this ; 
#!/usr/bin/perl
use strict;
    
my %ip1=();
my %ip2=();
while (<DATA>){
  my ($ts,$ip1,undef,$ip2,$length) = split /\s+/,$_;
  $ts =~ s/:(\d+)$/.$1/;
  my ($h,$m,$s) = split ':',$ts;
  my $sec = $s + ($m +($h*60))*60;
  
  my $key1 = join ' > ',$ip1,$ip2; 
  $ip1{$key1}{'sec'}    = $sec;
  $ip1{$key1}{'ts'}     = $ts;
  $ip1{$key1}{'length'} = $length;
  
  my $key2 = join ' > ',$ip2,$ip1;
  $ip2{$key2} = $key1; 
}

for my $key (sort keys %ip1){
  
  my $len1 = $ip1{$key}{'length'};
  my $ts1  = $ip1{$key}{'ts'};

  my $key2 = $ip2{$key};
  my $len2 = $ip1{$key2}{'length'};
  my $ts2  = $ip1{$key2}{'ts'};
  
  my $diff = $len1 - $len2;
  my $sec  = $ip1{$key}{'sec'} - $ip1{$key2}{'sec'}; 
  
  if ($diff > 0){
    print qq! 
    -------------------
    Received : $key
    At       : $ts1
    Length   : $len1
    Dur      : $sec
    
    Sent     : $key2
    At       : $ts2
    Length   : $len2 
    ---------------------!;
  }
}

__DATA__
17:40:36:692166859 89.X.X.X > 63.77.X.X 65
17:40:36:808642649 63.77.X.X > 89.X.X.X 140

[download]
poj

In reply to Re: Parsing my script out put? by poj
in thread Parsing my script out put? by Anonymous Monk

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.