Date | November 2018 | Marks available | 4 | Reference code | 18N.1.SL.TZ0.6 |
Level | SL | Paper | 1 | Time zone | no time zone |
Command term | Describe | Question number | 6 | Adapted from | N/A |
Question
Describe how data is transmitted by packet switching.
Markscheme
Award [4 max].
Packet switching entails data being separated into specially formatted units (packets);
Each packet contains data and information such as packet number, address that identifies the sending computer and intended recipient, etc.;
Packets are routed from source to destination using (different) network switches and routers;
Using these addresses, network switches and routers determine how best to transfer the packet on the path to its destination;
Packets are reassembled at the destination (using packet numbers);
If any of packets is missing it should be retransmitted;