Ch18

447 views
408 views

Published on

Published in: Technology
0 Comments
1 Like
Statistics
Notes
  • Be the first to comment

No Downloads
Views
Total views
447
On SlideShare
0
From Embeds
0
Number of Embeds
3
Actions
Shares
0
Downloads
22
Comments
0
Likes
1
Embeds 0
No embeds

No notes for slide

Ch18

  1. 1. Chapter 18 Domain Name System (DNS)
  2. 2. CONTENTS <ul><li>NAME SPACE </li></ul><ul><li>DOMAIN NAME SPACE </li></ul><ul><li>DISTRIBUTION OF NAME SPACE </li></ul><ul><li>DNS IN THE INTERNET </li></ul><ul><li>RESOLUTION </li></ul><ul><li>DNS MESSAGES </li></ul><ul><li>TYPES OF RECORDS </li></ul><ul><li>COMPRESSION </li></ul><ul><li>EXAMPLES </li></ul><ul><li>DDNS </li></ul><ul><li>ENCAPSULATION </li></ul>
  3. 3. NAME SPACE 18.1
  4. 4. DOMAIN NAME SPACE 18.2
  5. 5. Figure 18-1 Domain name space
  6. 6. Figure 18-2 Domain names and labels
  7. 7. Figure 18-3 FQDN and PQDN
  8. 8. Figure 18-4 Domains
  9. 9. DISTRIBUTION OF NAME SPACE 18.3
  10. 10. Figure 18-5 Hierarchy of name servers
  11. 11. Figure 18-6 Zones and domains
  12. 12. A primary server loads all information from the disk file; the secondary server loads all information from the the primary server. When the primary downloads information from the secondary, it is called zone transfer.
  13. 13. DNS IN THE INTERNET 18.4
  14. 14. Figure 18-7 DNS in the Internet
  15. 15. Figure 18-8 Generic domains
  16. 16. Figure 18-9 Country domains
  17. 17. Figure 18-10 Inverse domain
  18. 18. RESOLUTION 18.5
  19. 19. Figure 18-11 Recursive resolution
  20. 20. Figure 18-12 Iterative resolution
  21. 21. DNS MESSAGES 18.6
  22. 22. Figure 18-13 DNS messages
  23. 23. Figure 18-14 Query and response messages
  24. 24. Figure 18-15 Header format
  25. 25. Figure 18-16 QR: Query/Response OpCode: 0 standard, 1 inverse, 2 server status AA: Authoritative TC: Truncated RD: Recursion Desired RA: Recursion Available rCode: Status of the error Flags fields
  26. 26. TYPES OF RECORDS 18.7
  27. 27. Figure 18-17 Question record format
  28. 28. Figure 18-18 admin.atc.fhda.edu. Query name format
  29. 29. Figure 18-19 Resource record format
  30. 30. COMPRESSION 18.8
  31. 31. Figure 18-20 Format of an offset pointer
  32. 32. EXAMPLES 18.9
  33. 33. Example 1 A resolver sends a query message to a local server to find the IP address for the host “ chal.fhda.edu . ” . We discuss the query and response messages separately.
  34. 34. Figure 18-21 Example of a query message
  35. 35. Figure 18-22 Example of a response message
  36. 36. Example 2 An FTP server has received a packet from an FTP client with IP address 153.2.7.9. The FTP server wants to verify that the FTP client is an authorized client.
  37. 37. Figure 18-23 Example of inverse query message
  38. 38. Figure 18-24 Example of inverse response message
  39. 39. DDNS 18.10
  40. 40. ENCAPSULATION 18.11
  41. 41. DNS can use the services of UDP or TCP using the well-known port 53.

×