1. IPv4/6 Nirmala Shenoy Information Technology Department Rochester Institute of Technology

2. Internet Protocol Scope –IPv4 Purpose / Limitations –IPv4 features –IPv6 features –MobileIP –Integrated services in IP –Differentiated services in IP

3. Internet Protocol Purpose –To connect different types of local networks –To provide universal communications Unique addresses –To hide underlying NW technology/SW –Robust system – failures and congestion –Best effort delivery – data networks –No support for timely – reliable delivery

4. Internet Protocol Purpose –No support for wireless networks –Data forwarding protocols, with network ids –No error control / flow control ICMP –Connectionless datagram forwarding

5. Internet Protocol Layers –Comprises Layer 3 functions Forwarding Routing decisions Uses routing algorithms

6. Internet Protocol PDU

7. Internet Protocol PDU –VERS: version of the IP that created the datagram - current version is 4 –IHL : Internet header length in 32 bit words – due to IP options –TOTAL LENGTH: length of datagram in octets

8. Internet Protocol PDU –TYPE OF SERVICE –Precedence : (importance of the datagram) –type of transportation D- low delay T – high throughput R- high reliability C- minimize cost All bits 0 -normal service – D, T, R and C help in route selection

9. Internet Protocol PDU –IDENTIFICATION: unique id for each datagram –FLAGS D – datagram may be / may not be fragmented M – 0 last fragment, 1 more to come –FRAGMMENT OFFSET

10. Internet Protocol Fragmentation and reassembly

11. Internet Protocol PDU –Time to Live –PROTOCOL: Specifies which high level protocol was used to create the message, - UDP, TCP –IP OPTIONS: Not required in every datagram

12. Internet Protocol PDU –8 possible options: 0. end of options list 1. No operation – used for aligning octets between options 2. Security and handling restrictions 3. Loose source routing 4. Record time-stamp along a route 5. Stream identifier (obsolete) 6. Strict source routing 7. Record route

13. Internet Protocol Routing in Internet

14. Internet Protocol Routing in Internet

15. Internet Protocol –v6 Why IPv6? –IPv4 address extension using CIDR –Real time support –Mobility support –Flexible and efficient

16. Internet Protocol –v6 Aims of IPv6 –support huge amount of addresses –Reduce size of routing tables –Simplify protocol – router to process packets faster –Better security – authentication and privacy –Handle type of service – real-time data –Aid in multi-castings –Mobility of host –Protocol should be upgradable –Allow for old and new protocols to co-exist

17. Internet Protocol –v6 Features of IPv6 –addressing capabilities Address size increased from 32 to 128 bits More levels of address hierarchy Support new ‘anycast address’ –Quality of Service Capability Label packets for special handling during flow

18. Internet Protocol –v6 Features of IPv6 –Header Format Simplification Number of fields in header is reduced Header is of fixed length Fragmentation not allowed at routers –Only source can fragment

19. Internet Protocol –v6 Features of IPv6 –Improved Support for options Encoding of the options changed Router does not examine options (except hop-by-hop options) More efficient forwarding Less stringent limits on the length Greater flexibility for new options

20. Internet Protocol –v6 Features of IPv6 –Security IP level security Authentication and privacy supported

21. Internet Protocol –v6 PDU of IPv6

22. Internet Protocol –v6 PDU of IPv6 –Priority – Traffic class Route choosing Interactive class – low delay Real- time – path with less than 100ms delay

23. Internet Protocol –v6 PDU of IPv6 –Flow Label Performance guarantees Path establishment – id provided id to be used in all packets

24. Internet Protocol –v6 PDU of IPv6 –Next Header – 8 bits Id for the header following the IPv6 header could identify the additional (optional) extension headers if any

25. Internet Protocol –v6 PDU of IPv6 –Next Header –

26. Internet Protocol –v6 PDU of IPv6 –Next header Exists in IPv6 header and the Extension Header Used to identify the next header Extension headers are not processed by any node along the packet’s route (except the hop-by-hop options header)

27. Internet Protocol –v6 PDU of IPv6 –Destination options –Fragmentation options –Authentication –Payload security –Hop- by hop options –Extended routing

28. Internet Protocol –v6 Addressing in IPv6 –Unicast – an id for a single interface –Anycast – An id for a set of interfaces –Multicast- an id for a set of interfaces

29. Internet Protocol –v6 Addressing in IPv6 –Address Representation – hex notation X: X: X: X: X: X: X: X –Eg:FEDC:BA57:9874:C87B:98AC:7654:A B56:56AB –1080:0:0:0:800:200C:6:417A ( leading zeros can be omitted) –1080::800:200C:6:417A

30. Mobile Internet Protocol MobileIP –Use of portable computers on the Internet –Internet connection on migration –Issues IP addressing depends on connection to a network

31. Mobile Internet Protocol Ex: 160.80.40.20 –160.80 – IP address class B network number 8272 – 40.20 is the host number 10260 –Routing tables carry network id –packets routed based on the network id –Machine moves to a different network IP address changes

32. Mobile Internet Protocol MobileIP Features - ietf –Mobile host must to use its home IP address anywhere –No Software changes to fixed hosts –No Changes to router software and tables –Most packets for mobile hosts should not make detours on the way –No overheads while Mobile host is at home

33. Mobile Internet Protocol Routing to Mobile Hosts –Locate Host –Forward packet to host at current location

34. Mobile Internet Protocol Routing to Mobile Hosts –Locate Host

35. Mobile Internet Protocol Routing to Mobile Hosts –Locate Host Identify areas – LAN, wireless networks Each area has a Foreign Agent, Home Agent Home Agent –Responsible for roaming host –Has the details of its current position –Will forward messages to roaming host

36. Mobile Internet Protocol Routing to Mobile Hosts –Locate Host Foreign Agent –Responsible for foreign host in its territory –Roaming Host reports to Foreign Agent –Foreign Agent communicates to Home Agent –Foreign Agent is the c/o for messages to Mobile Host –Broadcasts itself

37. Mobile Internet Protocol Routing to Mobile Hosts –Locate Host Foreign Agent –Roaming user registers – giving its home address –Current data link layer address –Security information –FA authenticates from HA –Gives its address as c/o for the mobile node

38. Mobile Internet Protocol Routing to Mobile Hosts –Forwarding packets Packets addressed to Mobile host intercepted by HA HA encapsulates packet into a new IP packet with FA as destination and itself as Source and sends to FA – tunnelling FA removes encapsulation and forwards on layer 2 to roaming mobile

39. Mobile Internet Protocol Routing to Mobile Hosts –Forwarding packets OR HA gives FA address to sender of messages and forwards only the first message Subsequent messages are tunneled to FA from Sender directly bypassing home network

40. Mobile Internet Protocol Routing to Mobile Hosts –Forwarding packets

41. Integrated Service in Internet Proposed Services –Guaranteed services For intolerant applications Faithful playback – circuit emulation Eg: critical control appln

42. Integrated Service in Internet Proposed Services –Predicted services Tolerant to Qos loss Predict behavior and requirement from recent past Flow regulation required –Best effort services Elastic Applications

43. Integrated Service in Internet Proposed Services –Achieved through Controlled link sharing Resource reservation Admission control

44. Integrated Service in Internet Internet proposed solutions –Stateful Solutions Fair queuing under congestion Protection to well behaved traffic Better utilisation and quality assurance Integrated Services support - IntServ per flow quality guarantees

45. Integrated Service in Internet Internet proposed solutions –Stateless Solutions Packet dropping on congestion Identify packets into flow aggregates Service offered on aggregated traffic Scalable and Robust Differentiated Services - diffserv

46. Integrated Service in Internet Intserv support –Qos Specifications Intserv unaware hops Available path bandwidth Maximum path latency Maximum Packet size QoS service spec – token bucket based

47. Integrated Service in Internet Intserv support - Router features

48. Integrated Service in Internet Intserv support - Router features –Admission Control –Classifier –Packet Scheduler –Reservation set up protocols

49. Integrated Service in Internet Intserv support - Router features –Reservation set up protocols Helps provide sat up facilities for specific flow demands Message carries application requirements and goes though each and every router to the end node If successful in providing resources –Call accepted All routers enroute should handle

50. Integrated Service in Internet Intserv support - Router features –Reservation set up protocols Routing agents decide on the routes when such messages come by Passed to Reservation set up agent Communicates with the admission control Who check if the call can be supported If so – reservation agents makes bookings

51. Integrated Service in Internet Intserv support - Router features –Classifier Classifies incoming packets into proper queues for appropriate handling Classes can be one flow, multiple flows All packets belonging to one class are handled identically by the scheduler

52. Integrated Service in Internet Intserv support - Router features –Packet scheduler Schedules based on each flow requirement Uses queues and timers Priority only Weighted fair queuing Packet dropping under congestion Sets congestion control mechanisms

53. Integrated Service in Internet Intserv support - Router features Estimator Measures actual outgoing traffic Useful for the admission control Policing Classifying flows Destination address, source address, ports Flow-id – IPv6

54. Differentiated Service in Internet –Packet are classified into traffic aggregates –Service provided to traffic aggregates –Complexity only at boundary nodes Classification Conditioning Shaping –Interior nodes – no states

55. Differentiated Service in Internet –Interior nodes – no states Per hop behavior (PHB) defined for each traffic class TOS field used as DS field – diffserv field Decouples service from applications Decouples traffic conditioning and service provisioning from forwarding Scalable Robust

56. Differentiated Service in Internet –DS domain Nodes operating within a common service provisioning Across domains – Service Level Agreements

57. Differentiated Service in Internet –Diffserv routers Packet classifier –Classfies –Forwards to appropriate traffic conditioner Traffic conditioning –Metering, shaping, policing, remarking based on subsequent domains

58. Differentiated Service in Internet –Summary High popularity Limited capability Backward compatibility Retro-fit? Will IPng be the solution? Real –time support? Wireless support? High bit rate applications?