2.1 · Lesson 2 of 3
Packets and packet switching
Syllabus 2.1.1Syllabus 2.1.2Syllabus 2.1.3
What this lesson covers
- Explain why data is split into packets
- Describe the structure of a packet
- Describe packet switching
Key vocabulary
- Hop count
- A limit on how many routers a packet can pass through before it's deleted.
- Protocol
- A set of rules that controls how data is sent across a network.
- Packet
- A small chunk of a file that is sent across a network on its own.
- Packet header
- The part of a packet holding the destination address, the originator's address and the packet number.
- Payload
- The part of a packet holding the actual data being sent.
- Trailer
- The part of a packet that marks its end. Sometimes called the footer.
- Packet switching
- Sending the packets of a file separately, possibly by different routes, then reordering them when they arrive.
- Router
- A device that decides which route each packet takes across a network.
Check your learning
- Quick check: 4 questions
- Key vocabulary test: 8 terms
- Activity 1: Packets quiz · 8 questions
- Activity 2: Be the receiver · 6 questions
- Activity 3: Packet switching steps · drag and drop