my $pcapPayload = Net::Pcap::open_offline($pcapFile,\$error);

while (my $pkt = Net::Pcap::next($pcapPayload, \%pcapHeader))
{
   my $ether_data = NetPacket::Ethernet::strip($pkt);
   my $ether_obj = NetPacket::Ethernet->decode($pkt);
   my $ip = NetPacket::IP->decode($ether_obj->{'data'});
   ...
}