What is protocol header?

Related questions

1. What TCP header contains?
2. Can UDP be fragmented?
3. What is header length in IP header?
4. Is port 80 UDP or TCP?
5. How many bytes is a TCP header?
6. Is port 443 encrypted?
7. Where is UDP used?
8. How does UDP header differ from TCP header?
9. What is in the UDP header?
10. Is TCP or UDP better?

Tags

1. #packet
2. #communication
3. #network
4. #contain
5. #destination
6. #information
7. #addresses
8. #source
9. #usage
10. #lengths
11. #headers
12. #contains
13. #containing
14. #normally
15. #fixed
16. #header
17. #version
18. #variable
19. #including
20. #application
21. #internet
22. #protocol
23. #bytes