The Destination Address (Layer 2 or Layer 3)
the router will enqueue the packet that is sent to the destination 192.168.1.4.and then that packet is sent on transmission media(cable).it checks every ip address that is holding the ip same as the destination ,if it reaches there then it deleiver it on that machine.
The router discards the packet. The router forwards the packet via the default route
First, routing is the process a router performs when making forwarding decisions for each packet arriving at the gateway interface. To forward a packet to a destination network, the router requires a route to that network. If a route to a destination network does not exist on the router, the packet will be forwarded to the default gateway. Now, the destination network can be a number of routers or hops away from the default gateway. If the router has an entry for the network in its routing table, it would only indicate the next-hop router to which the packet is to be forwarded to and not the exact route to the final router. To sum it up, the routing process uses a routing table to map the destination address to the next hop and then forwards the packet to the next-hop address.
Router uses IP address of destination node to do the direct packet switching..while bridge & switch uses the MAC address to packet forwarding.
First, routing is the process a router performs when making forwarding decisions for each packet arriving at the gateway interface. To forward a packet to a destination network, the router requires a route to that network. If a route to a destination network does not exist on the router, the packet will be forwarded to the default gateway. Now, the destination network can be a number of routers or hops away from the default gateway. If the router has an entry for the network in its routing table, it would only indicate the next-hop router to which the packet is to be forwarded to and not the exact route to the final router. To sum it up, the routing process uses a routing table to map the destination address to the next hop and then forwards the packet to the next-hop address.
--> If the destination network is directly connected, the router forwards the packet to the destination host. --> If no route exists for the destination network and a default route is present, the packet is forwarded to the next-hop router. --> If the originating host has a default gateway configured, the packet for a remote network can be forwarded using that route.
packet-filtering
Route table lookup
It uses the MAC address, Media Access Control. Every packet sent from a computer contains its MAC address. The router stores this in its routing table. When it receives a packet with a destiation address of that MAC address, then it forwards it to that computer. This is called NAT, Network Address Translation. It uses the Destination IP address
Since Facebook uses a limited range of IP addresses, blocking those addresses on the router will effectively deny access to Facebook.
A router is a device that decides where to send a data packet in order to get it one step closer to its destination, and then sends it there.In order to make this decision, the router looks at the destination address on the packet and then consults a list of rules programmed into the router by the person who set it up.If there is no explicit rule covering this packet - if the router hasn't been programmed with a rule on how to route packets to this particular destination - then the router send the packet to the default route.In other words, the default route is the destination that a packet is sent to if the router doesn't have instructions to send it somewhere else.As an example, consider a simple home router that connects your home network to the Internet. This router will have two routing rules - one for computers on your internal network, and a default route. The default route will send packets upstream to your ISP. So any packet that's not going to another computer at your house will always be sent out to the Internet.HTH,Gdunge