Question is in the subject…
What is better; advantages/disadvantages ?
D.
*sorry for posting into Wireless Networking, can’t delete it or move now 
you have to tell about requirements too.
I suppose you are asking about PPPoE or Masquerade+static_ARP.
PPPoE requires additional settings configuration on the clients side, static ARP doesn’t require configuration on the CPE.
Another solution is HotSpot for the network security, probably one of the most flexible solutions.
You can search in the forum, the similar topics were discussed here.
Yes, that’s right, just wanted to help others (like myself) trying to find around the forum…
so, let me refrase the question : using MikroTik as router (and PPPoE AC, and “link” to the Internet), with users connecting via PPPoE (doesn’t matter if they use wifi pci card or notebook or cpe or sqf or ffidj or whatever 
) what is better solution to route THEM (pppoe conencted users) to internet :
- to use same subnet as one MT connects to Internet (like, IP to WAN is 10.10.10.200 and give users 10.10.10.1-100) or,
- NAT masquarade WAN so users can get whatever addresses they like
// I see, now, that having more than 200 users would be the problem if using proxy-arp ?