What is the difference between a bridge and a router in RouterOS?

• A. A bridge operates at layer 2 to forward frames within the same broadcast domain; a router operates at layer 3 to make IP routing decisions between networks.
• B. A bridge uses IP routing, while a router forwards frames within a broadcast domain.
• C. A bridge is used for NAT, while a router is used for switching.
• D. A bridge is for wireless networks, a router for wired networks.

Answer: (A)

At the networking level, a bridge operates at layer 2 and forwards frames based on MAC addresses within the same broadcast domain. It doesn’t look at IP addresses or route between networks, so all devices connected through a bridge effectively share one LAN where broadcasts reach every port.

A router, on the other hand, works at layer 3 and makes decisions based on IP addresses to route packets between different networks or subnets. It separates broadcast domains, allowing communication across distinct networks and often providing mechanisms like NAT and firewalling.

So, in RouterOS terms, a bridge ties interfaces together as one LAN at layer 2, while a router connects networks and handles IP routing at layer 3. The other statements mix up these roles: bridges don’t perform IP routing, NAT is a router function, and bridges aren’t limited to wireless versus wired usage.