Do routers reassemble fragmented packets?

Routers fragment packets, but they don’t actually reassemble the fragments; that is up to the destination device. RFC 791, Internet Protocol, leaves open the possibility of routers doing reassembly, but that doesn’t happen in practice, unless the router is the packet destination.

What happens when a router forwards data packets from one network to another network?

A packet is typically forwarded from one router to another router through the networks that constitute an internetwork (e.g. the Internet) until it reaches its destination node. Then, using information in its routing table or routing policy, it directs the packet to the next network on its journey.

What happens when a packet arrives at a router?

When a router receives a packet, the router checks its routing table to determine if the destination address is for a system on one of it’s attached networks or if the message must be forwarded through another router. It then sends the message to the next system in the path to the destination.

How do packets and routers work together?

Router. A smart device that directs or routes information around the internet. When a data packet arrives the router reads the IP address information and sends the packet along the best route to its destination.

Do routers fragment packets?

IP Fragmentation If a packet exceeds the Maximum Transmission Unit (MTU) of a network, a router along the path may fragment it. An MTU is the maximum PDU size on a network. Fragmentation breaks a large packet into multiple smaller packets.

How do I know if packets are fragmented?

You must also look at the Fragment offset field, but that by itself is not sufficient because the first packet fragment will have that field set to 0. If the Fragment Offset field > 0 then it is a packet fragment, or if the Fragment Offset field = 0 and the MF flag is set then it is a fragment packet.

Why do routers not forward broadcast packets?

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.

Do routers send frames or packets?

A router (with an Ethernet interface) sends packets inside of frames. This is what “encapsulation” is about.

How are packets delivered?

Using routing protocols and its own routing table, the default gateway figures out the best path to the destination. Using the many routers throughout the internet, the data packet is routed and delivered to the default gateway of the destination network.

Do packets have to arrive in the same order in which they were sent?

The IP protocol deals only with packets, and TCP enables two hosts to establish a connection and exchange streams of data. TCP guarantees delivery of data and also guarantees that packets will be delivered in the same order in which they were sent.

How does a packet get routed?

When a packet arrives at a router, the router examines the IP address put there by the IP protocol layer on the originating computer. The router checks it’s routing table. If the network containing the IP address is found, the packet is sent to that network.