This is a simplified presentation on the Diff Serv field in the IPv4 and IPv6. It was used to give laymen knowledge on the topic.

1. DIFFERENTIATED
SERVICES

2. WHY?

3. NETWORK
TRAFFIC

4. SOME
CATEGORIES OF
NETWORK
TRAFFIC
REQUIRE
PREFERNTIAL
TREATMENT

5. ONLINE
GAMING

6. VOIP

7. STREAMING
MEDIA

8. ROUTINE
NETWORK
TRAFFIC
TREATED
NORMALLY
“BEST
EFFORT”

11. GAURANTEED
PERFORMANCE
RESERVE
NETWORK
CAPACITY
MEASUREMENT
• BIT RATE
• DELAY
• PACKET DROP
PROBABILITY
• BIT ERROR RATE

12. DIFFERENTIATED
SERVICES

14. TOS FD

16. DS FD

17. DIFF
SERV
6-BIT DS
FD -
DSCP
TOS FD
OF IPv4
TRAFFIC
CLASS
IN IPv6
SIMPLE
WIDELY
USED
QoS

18. DIFF SERV WORKS
ON THE BASIS OF
“TRAFFIC
CLASSIFICATION”

19. TRAFFIC CL

20. TRAFFIC CL
RATE
LIMITING
TRAFFIC
POLICING/
SHAPING

21. NETWORK TRAFFIC POLICING

22. NETWORK TRAFFIC POLICING

23. ROUTERS IMPLEMENT
“PER HOP BEHAVIOUR
(PHB)”

24. BEST EFFORT
PHB

25. SERVICE DEPENDENT ON
TRAFFIC CONDITIONS

28. EXPEDITED
FORWARDING
PHB

29. EF
LOW LOSS
LOW
LATENCY
STRICT
PRIORITY
QUEUING
STRICT
CONTROL
BY ISP ~
30%

30. PRIORITY QUEUING

31. EF
LOW LOSS
LOW
LATENCY
STRICT
PRIORITY
QUEUING
STRICT
CONTROL
BY ISP ~
30%

32. EXPEDITED FORWARDING PHB

33. ASSURED
FORWARDING
PHB

34. ASSURED FORWARDING

35. • ASSURANCE OF DELIVERY
• STATE OF TFC CONDITION
• CONTROLLED
ASSURED FORWARDING

36. ASSURED FORWARDING
CLASS 1
(LOWEST)
CLASS 2 CLASS 3
CLASS 4
(HIGHEST)
LOW
DROP
DSCP 10 DSCP 18 DSCP 26 DSCP 34
MED
DROP
DSCP 12 DSCP 20 DSCP 28 DSCP 36
HIGH
DROP
DSCP 14 DSCP 22 DSCP 30 DSCP 38
Q

37. CLASS
SELECTOR (CS)
PHB
“XXX000”

38. CLASS SELECTOR PHB

39. DESIGN
CONSIDERATIONS

40. DESIGN CONSIDERATIONS

41. RECAP
QoS
DSCP – IPv4
& IPv6
TFC CL
PHB
• BEST EFFORT
• EF
• AF
QUEUING
TECHNIQUES
DESIGN

42. REFERENCE & FURTHER
READING
RFC 2474 DEFINITION OF THE DIFFERENTIATED SERVICES FIELD (DS FIELD) IN THE IPV4 AND
IPV6 HEADERS
RFC 2475 ARCHITECTURE FOR DIFFERENTIATED SERVICES
RFC 2597 ASSURED FORWARDING PHB GROUP
RFC 2983 DIFFERENTIATED SERVICES AND TUNNELS
RFC 3086 DEFINITION OF DIFFERENTIATED SERVICES PER DOMAIN BEHAVIORS AND RULES
FOR THEIR SPECIFICATION
RFC 3140 PER HOP BEHAVIOR IDENTIFICATION CODES
RFC 3246 AN EXPEDITED FORWARDING PHB
RFC 3247 SUPPLEMENTAL INFORMATION FOR THE NEW DEFINITION OF THE EF PHB

43. REFERENCE & FURTHER
READING
RFC 3260 NEW TERMINOLOGY AND CLARIFICATIONS FOR DIFFSERV
RFC 4594 CONFIGURATION GUIDELINES FOR DIFFSERV SERVICE CLASSES
RFC 5865 A DIFFERENTIATED SERVICES CODE POINT (DSCP) FOR CAPACITY-ADMITTED
TRAFFIC
RFC 3289 MANAGEMENT INFORMATION BASE FOR THE DIFFERENTIATED SERVICES
ARCHITECTURE
RFC 3290 AN INFORMAL MANAGEMENT MODEL FOR DIFFERENTIATED SERVICES ROUTERS
RFC 3317 DIFFERENTIATED SERVICES QUALITY OF SERVICE POLICY INFORMATION BASE