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03 - Main components of a packet

 1. Networks send and receive data in small chunks called ………………..

  CPU units

  sequences

  bits

  packets

 2. A packet has the following components. When is the reassembly information used?
A source address specifying the sending computer
A destination address specifying where the packet is being sent
Instructions telling the computer how to pass the data on
Reassembly information
The data to be transmitted to the remote computer (often called the packet payload)
Error-checking information to ensure that the data arrives intact

  if the packet is made up of a single bit or byte

  if the packet is part of a longer message)

  None of the above

  if the packet is on its own with no additional parts

 3. Each packet consists of the following parts:

  Data

  Trailer

  All of the above

  Header

 4. This typically includes an alert signal to indicate that the data is being transmitted, source and destination addresses and clock information to synchronise the transmission.

  header

  trailer

  data

  router

 5. The contents of the trailer (or even its existence) can vary among network types, but it normally includes a Cyclic Redundancy Checksum (CRC) which lets ……………

  the network delete packets if they are corrupt

  the network determine whether or not a packet has been damaged in transmission.

  the network act as a router or gateway

  None of the above

 6. All packets have a header and payload.

  FALSE

  TRUE

 7. What is the purpose of the header?

  To ensure the data has been correctly transmitted

  To carry the data in the packet

  To provide a page banner in the web browser

  To provide instructions about the data in the packet

 8. What are the 'fields' in the header?
componentsofapacket_q3.jpg

  Categories of information

  Spaces for the data in the packet

  Places for crop rotation

  A hashing algorithm

 9. How many fields are in the header in IPv4?

  22

  9

  4

  14

 10. What information is contained in the version field?

  Whether the data is packet or circuit switched

  The length of the packet

  The optimal web browser

  The Internet Protocol

 11. What is ECN?
componentsofapacket_q6.jpg

  Early Correspondence Notice

  Estimated Connection Number

  Explicit Congestion Notification

  Every Computer Now

 12. In IPv4, the header contains a checksum to error check the header.

  TRUE

  FALSE

 13. What information is contained in the payload?

  The actual data being transmitted across the network

  The total size of the packet

  The value of the packet

  The destination for the data transmitted

 14. What can a trailer be used for?
componentsofapacket_q9.jpg

  To ensure the packet can hold the weight of the data

  To indicate the end of the packet and to error check

  To prepare a route for the next packet

  To carry left over data from the payload

 15. Counting the 1s in the payload and comparing this value against a value stored in the trailer is an example of a …

  Multiple Recursive Analysis (MRA)

  Error Revisional Diagnosis (ERD)

  Endless Loop Reversion (ELR)

  Cyclic Redundancy Check (CRC)