/ip firewall filter
add chain=forward src-address=0.0.0.0 dst-address=0.0.0.0 action=drop comment="Bloqueio de comunica  o cliente a cliente" disabled=no 
add chain=forward protocol=tcp dst-port=137-139 action=drop comment="Net Bios tcp" disabled=no 
add chain=forward protocol=tcp dst-port=445 action=drop comment="NetBios" disabled=no 