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Do routers forward broadcast by default?
A router does not by default forward a packet with an IP broadcast address. Protocols using broadcast packets normally only operate within a single broadcast domain. (Routers can sometimes be specifically configured to support this.)
How does a router handle broadcast?
Generally speaking, routers will unicast-forward incoming packets which have a network broadcast address as destination, unless they are directly connected to that network/subnet and therefore know that the destination address is a broadcast address.
What is the directed broadcast of the network?
A directed broadcast is an IP broadcast to all devices within a single directly-attached network or subnet. A net-directed broadcast goes to all devices on a given network. A subnet-directed broadcast goes to all devices within a given subnet.
Does a router forward broadcast frames?
A broadcast frame is a frame that goes to all network stations on a LAN. At the data link layer, the destination address of a broadcast frame is FF:FF:FF:FF:FF:FF (all 1s in binary). A router does not forward broadcasts or multicasts. All devices on one side of a router are considered part of a single broadcast domain.
When does a router use an IP directed broadcast?
A router that needs to send data to a remote IP host when only the IP network address is known uses an IP directed broadcast to reach the remote host.
How does broadcast routing work on different networks?
The router checks if the packet is a DHCP Offer then rewrites the packet to become a broadcast packet and sends it back out that interface knowing that the DHCP client is somewhere on that network segment. The packet leaving the router now looks like this. Destination IP: 255.255.255.255
Can a router forward a network broadcast address?
Generally speaking routers will not forward incoming packets which have the network broadcast address as destination. You may want to add some precision or context to that statement. It is only true for routers that have an interface into that subnet and thus know that what the network broadcast address of that subnet happens to be.
What is the host address of a directed broadcast?
It is limited because it is never forwarded across a router, unlike a directed broadcast. The directed (also called net-directed) broadcast address of the 192.0.2.0/24 network is 192.0.2.255 (the host portion of the address is all 1s in binary, or 255).