Understanding IPv6: Addressing the Limitations of IPv4 and Embracing the Future

1. Introduction "Internet Protocol version 6" Presenter Veena Merz Manager Cisco Networking Area Academy

2. Why a new Version for IP ? Objective • To describes the problems of the IPv4 Internet and how they are solved by IPv6. IPv6 Introduction

3. IPv4 • The current version of IP (known as Version 4 or IPv4) has not been substantially changed since RFC 791 was published in 1981. • IPv4 has proven to be robust, easily implemented and interoperable • It has stood the test of scaling an internetwork to a global utility the size of today’s Internet. • This is a tribute to its initial design. IPv6 Introduction

4. Historical Facts In 1983 Research network for ~ 100 computers IPv6 Introduction

5. Limitations of IPv4 • 1992 : Commercial activity and exponential growth • The recent exponential growth of the Internet and the impending exhaustion of the IPv4 address space. • IPv4 addresses have become relatively scarce, forcing some organizations to use a Network Address Translator (NAT) to map multiple private addresses to a single public IP address. • While NATs promote reuse of the private address space, they do not support standards-based network layer security or the correct mapping of all higher layer protocols • Additionally, the rising prominence of Internet-connected devices and appliances ensures that the public IPv4 address space will eventually be depleted. IPv6 Introduction

6. Limitations of IPv4 • The growth of the Internet and the ability of Internet backbone routers to maintain large routing tables. • Because of the way that IPv4 address prefixes have been and are currently allocated, there are routinely over 85,000 routes in the routing tables of Internet backbone routers. • The current IPv4 Internet routing infrastructure is a combination of both flat and hierarchical routing. IPv6 Introduction

7. Limitations of IPv4 • The need for simpler configuration. • Most current IPv4 implementations must be either manually configured or use a stateful address configuration protocol such as Dynamic Host Configuration Protocol (DHCP). • With more computers and devices using IP, there is a need for a simpler and more automatic configuration of addresses and other configuration settings that do not rely on the administration of a DHCP infrastructure. IPv6 Introduction

8. Limitations of IPv4 • The requirement for security at the IP level • Private communication over a public medium like the Internet requires encryption services that protect the data being sent from being viewed or modified in transit. • Although a standard now exists for providing security for IPv4 packets (known as Internet Protocol security or IPsec), this standard is optional and proprietary solutions are prevalent. IPv6 Introduction

9. Limitations of IPv4 • The need for better support for real-time delivery of data—also called quality of service (QoS) • While standards for QoS exist for IPv4, real-time traffic support relies on the IPv4 Type of Service (TOS) field and the identification of the payload, typically using a UDP or TCP port. • Unfortunately, the IPv4 TOS field has limited functionality and over time there were various local interpretations. • In addition, payload identification using a TCP and UDP port is not possible when the IPv4 packet payload is encrypted. IPv6 Introduction

10. IPv4/8 Address Space Status (Sept. 2005) Sources from NRO(Number Resource Organization) IPv6 Introduction

11. Status of 256 /8sIPv4 Address Space http://www.potaroo.net/tools/ipv4/index.html IPv6 Introduction

12. IPv4 AllocationsRIRs to LIRs/ISPs Yearly Comparison IPv6 Introduction

13. IPv4 AllocationsRIRs to LIRs/ISPs IPv6 Introduction

14. ASN AssignmentsRIRs to LIRs/ISPs Yearly Comparison IPv6 Introduction

15. ASN AssignmentsRIRs to LIRs/ISPs Cumulative Total (Jan 1999 – Jun 2007) IPv6 Introduction

16. IANA IPv6 Allocations to RIRs issued as /23s prior to Oct 06 IPv6 Introduction

17. IANA IPv6 Allocations to RIRs issued Oct 06 IPv6 Introduction

18. IPv6 Allocations RIRs to LIRs/ISPs Yearly Comparison IPv6 Introduction

19. IPv6 AllocationsRIRs to LIRs/ISPs Cumulative Total (Jan 1999 – Jun 2007) IPv6 Introduction

20. Links to RIR Statistics • RIR Stats:www.nro.net/statistics • Raw Data/Historical RIR Allocations:www.aso.icann.org/stats www.iana.org/assignments/ipv4-address-space www.iana.org/assignments/as-numbers www.iana.org/assignments/ipv6-unicast-address-assignments IPv6 Introduction

21. Emergency Measures

22. 1. CIDR … • Allocate exceptionally class B addresses • Re-use class C address space • CIDR (Classless Internet Domain Routing) • RFC 1519 (PS) • network address = prefix/prefix length • less address waste • allows aggregation (reduces routing table size) IPv6 Introduction

23. Advantages Reduce the need of official addresses Ease the internal addressing plan Transparent to some applications “Security”–Netadmins/sysadmin Disadvantages Translation sometime complex (e.g. FTP) Apps using dynamic ports Does not scale Introduce states inside the network: Multihomednetworks Breaks the end-to-end paradigm– Security with IPsec=> 2. NAT IPv6 Introduction

24. 3. Private Addresses(RFC 1918 BCP) • Allow private addressing plans • Addresses are used internally • Similar to security architecture with firewall • Use of proxies or NAT to go outside • RFC 1631, 2663 and 2993 • NAT-PT is the most commonly used of NAT variations IPv6 Introduction

25. IPv6 …….

26. IPv6: Background The recommended proposal was SIPP with 126 bit address size. IPv6 Introduction

27. Architects of IPv6 ProtocolSteven Deering and Robert Hinden IPv6 Introduction

28. History of IPv6 IPv6 Introduction

29. IPv6 Features • New header format • Large address space • Efficient and hierarchical addressing and routing infrastructure • Stateless and stateful address configuration • Built-in security • Better support for prioritized delivery • New protocol for neighboring node interaction • Extensibility IPv6 Introduction

30. What about IP Version 5 (IPv5) ?

31. IPv5 Overview • The Internet Stream Protocol (ST) was an experimental protocol defined in 1979 in IEN 119 (Internet Engineering Note), and was later revised in RFC 1190 (ST2) and RFC 1819 (ST2+). • ST was experimental packet carrying non - IP real- time stream protocol. • ST was envisioned to be the connection oriented complement to IPv4, but it has never been introduced for public usage. • Many of the concepts available in ST can be found today in MPLS. • IPv5 never existed. • In datagram mode, ST was assigned Internet Protocol version number 5. • The version number "5" in the IP header was assigned to ST. • ST was never widely used, but since the version number 5 had already been allocated the new version IPv6 Introduction

32. Viewing Global Routing Table C:/>telnet router-server.ip.att.net IPv6 Introduction

33. Viewing Global Routing Table IPv6 Introduction

34. Viewing Global Routing Table IPv6 Introduction

35. Q & A