#!/usr/bin/perl
use strict;
use warnings;

use constant STATUS  => 0;
use constant REQUEST => 1;

# Some code that initializes %list
# In the form
# $list{ $nas }[STATUS]  = $response_status;
# $list{ $nas }[REQUEST] = $request_date_time

# Later on you can retrieve the status and request like

my $mac = ''; # actual code to get MAC from log
my $status  = $list{ $mac }[STATUS];
my $request = $list{ $mac }[REQUEST];