...open LOGFILE...
my (@list, %info);
while (<LOGFILE>) {
  if (/^Frame /) { # detect start of new data record
    if (%info) { push(@list, { %info }) } # save last collected record
    %info = ();    # start with blank record
  } elsif (/^  *Source port: (\S+)\s+(\S+)/) {
    $info{source_port} = $1; # also save $2?
  } elsif (/^  *Destination port: (\S+)\s+(\S+)/) {
    $info{dest_port} = $1;
  } elsif (/^[\da-f]{4}\s+[\da-f\s]+/i) {
      push(@{$info{data}}, $_);  # save data lines
  }
}
if (%info) { # must check at end of loop
  push(@list, { %info }); 
}
# @list contains parsed Frame records

##</code><code>##

my $bytes;
for my $line (@{$info->{data}}) {
  if ($line =~ m/^[\da-f]{4}\s*(([\da-f]{2} )+)/i) {
    my $hex = $1;
    $hex =~ s/\s//g;
    $bytes .= pack("H*", $hex);
  }
}