How to get public ip's on a second routeros

Hello Community,
I have a question about routeros I tried a lot of simulation on lab but I cant find the right way to configure this scenario.
I have a router A with some public ip’s from a fiber connection, this router is using just a few addresses for the management network, i want to find a way to assign the other public ip’s on an other router (B) so this router will serve an other company network.

In case of Scenario B is a possible solution can I put a switch on the ISP modem and connect there both routers and assign on each router the public ip i want??

Thanks
scenario b.jpg
distribuzioneip.jpg

On router A, create a bridge (e.g. named br-wan), move all the IP configuration from ether1 to that bridge (don’t forget about the firewall!), and make both ether1 and ether3 member ports of that bridge.

I’m a bit confused on how to manage all mangle and firewall rules so is it possible to add also a phisical bridge device like in picture?

ISP gives me 1.1.1.1-4 so I configure:

Router A 1.1.1.1 and 1.1.1.2
Router B 1.1.1.3 and 1.1.1.4

Right??

Thanks for helping me!!
Schermata 2019-12-02 alle 22.07.31.png

Yes, you can use a physical switch like on the picture, or you can create the bridge inside one of the Mikrotiks the way I’ve suggested before. In either case, you don’t need to add any mangle rules for this to work, as all the public IPs are in a single subnet and on the same L2 segment. With a physical switch, you keep all the L3 (IP) configuration (including firewall rules) in Router A attached to ether1; with a bridge in Router A (/interface bridge add name=br-wan ; /interface bridge port { add bridge=br-wan interface=ether1; add bridge=br-wan interface=ether3 }), you just replace ether1 by br-wan in all L3 configurations where it is eventually used (/ip address rows, all firewall rules, /interface list member rows) to get the same result.

Thanks, I really appreciate it…

Thanks for help.