use strict;
use warnings;
my %hash = ();
my ($time, $conference, $type,$comment);
while(<FILE>)
{
   # adapt parsing values to your need here

   if (/conference=(.*)/){
       $time = $1;
   }
   if (/conference=(.*)/){
       $conference = $1;
   }
   if (/type=(.*)/){
       $type = $1;
   }
   if (/comment=(.*)/){
       $comment = $1;
   }
   if (/lastline of record/){
      $hash{$time,$conference}{time}       = $time;
      $hash{$time,$conference}{conference} = $conference;  # info is already in the key, for easy parsing in the for loop, store conference twice.
      $hash{$time,$conference}{type}       = $type;
      $hash{$time,$conference}{comment}    = $comment;
   }
}

for my $timeconference (sort keys %hash)
{
   printf "time %s, conference %s, type %s, comment %s\n",
          @{hash}{qw(time conference type comment)};
}