IPv6- End User Perspective Fakhar Mirza CCNA, CCSP, CCIE Head of Technical, NETS

1. IPv6- End User Perspective FakharMirza CCNA, CCSP, CCIE Head of Technical, NETS

2. Agenda • Understanding need for IPv6 • History of IPv4 Internet • Modern Internet • Needs of Modern Internet • Understanding IPv6 Direct/Indirect Communication • IPv6 Communication in LAN • IPv6 Communication over WAN • IPv6 Migration Strategies • Understanding Impact on Hardware and Software • Techniques of Partial and Full Migration • IPv6 Applications and Services • Enabling IPv6 in LAN • Enabling IPv6 in WAN • Using Applications and Services via IPv6

3. History of IPv4 Internet

4. History of Internet • Advanced Research Projects Agency of the Department of Defense (ARPA) • Implemented the ARPAnet, the grandparent of today’s Internet • Packet switching • Digital data is sent in small packages called packets • Packets • Contain data, address information, error-control information and sequencing information • Transmission Control Protocol (TCP) • ensures that messages are properly sent from sender to receiver and that those messages arriveintact

5. History of Internet … contd. • Internetworking Protocol (IP) • De-facto Standard • Enabled the intercommunication of inter-organization and intra-organization packet based networks. • The Internet was initially limited to universities and research institutions

6. History of Internet - Addresses • How to get there from here!!! • Addresses provide information on how to locate something, e.g., what route to take from here to there. • Internet addresses combine • a routing portion, known as the network part • a name portion known as the host part • How to split an Internet address into the network part and the host part has changed over time…

7. History of Internet – Addresses … contd. • Back when the TCP/IP protocols were first being designed, there was a big argument between fixed length and variable length addresses • Fixed length will always be limited • But if you make it big enough, no one will be interested • Variable length will always take more cycles to process • But there are tricks you can play to minimize the difference • The decision was made for fixed, 32 bit addresses • Rumor has it, by a flip of a coin...

8. History of Internet – Internet Address Structure • 32 bit unsigned integers • possible values 0 - 4,294,967,295 • Typically written as a “dotted quad of octets” • four 8 bit values with a range of 0-255 separated by “.” • For example, 202.12.28.129 can be written as below

9. History of Internet … Internet Address Structure E • Originally, the architects of the Internet thought 256 networks would be more than enough • Assumed a few very large (16,777,216 hosts) networks • Addresses were partitioned as below • 8 bit network part, 24 bit host part

10. History of Internet – Classfull Addressing • Original addressing plan too limiting • More than 256 networks with many fewer hosts than 224 • Solution was to create address classes

11. History of Internet – Internet Address The Problem • Class A way too big • 16 million hosts in a flat network is unthinkable • Class B too big • Even 65536 host addresses is too many in most cases • Imagine 65534 hosts all responding to a broadcast • Class C too small • Most sites initially connecting to the Internet were large Universities, 256 was too small for them • Need more flexibility!

12. History of Internet – Classless Addressing • Classfull addressing was a better fit than original • but class A and B networks impossible to manage • Solution was to partition large networks internally into sub-networks (subnets)

13. History of Internet – Classless Addressing … contd. • Prefix 202.12.28.0/22 • 1024 host addresses • announced as a single network (CIDR - Supernetting) • Consists of 7 subnets • 202.12.28.0/25 • 202.12.28.128/26 • 202.12.28.192/26 • 202.12.29.0/24 • 202.12.30.0/24 • 202.12.31.0/25 • 202.12.31.128/25 • Subnetting/VLSM !!!

14. History of Internet … contd. • Things went OK and life started sailing smooth … • What happened then ?

15. Modern Internet

16. Modern Internet – New Problems … New Solutions • IPv4 addresses particularly limited • Some U.S. universities and corporations have more IPv4 address space than some countries • Upcoming demise of IPv4 address space predicted since mid 1990’s • NAT + RFC 1918 has slowed that demise • 90% of Fortune 1000 companies use NAT

17. Modern Internet – New Problems … New Solutions • Breaks globally unique address model • Breaks address stability • Breaks always-on model • Breaks peer-to-peer model • Breaks some applications • Breaks some security protocols • Breaks some QoS functions • Introduces a false sense of security • Introduces hidden costs

18. Modern Internet … Mobile IP • Mobile nodes must be able to move from router to router without losing end-to-end connection • Home address: Maintains connectivity • Care-of address: Maintains route-ability • Mobile IP will require millions or billions of care-of addresses

19. Modern Internet … Peer to Peer Networking • Every host is a client and a server • That is, a consumer and a producer P2P: A group of nodes actively participating in the computing process

20. Modern Internet … Many More • Online Gaming • Social Networking • Internet Enabled Appliances • Electrolux Screenfridge • Samsung Digital Network Refrigerator • Internet Enabled Auto-Mobiles • GPS Maps • Tracking etc. • Internet Enabled ATMs • Smart Sensors • A never ending wish list …

21. Conclusion World Population = 6B+ IPv4 Addresses = 4.2B (including RFC1918, Class D and Class E) Solution = IPv6 Seems like Internet Address is probably the most precious thing in this world and they are the species at brink … We need more addresses and IPv4 has 32bits fixed limit.

22. Conclusion … contd.

23. Conclusion … contd. World Population = 6B+ IPv6 Addresses = 340T+ • For billions of new users • For billions of new devices • For always-on access • For transparent Internet connectivitythe way it was meant to be

24. IPv4 & IPv6 – Similarities and Differences

25. IPv4 & IPv6 – Similarities and Differences

26. IPv6 – New Features • Header Length Increased 40B • Hexadecimal Address Format • “:” will be used as delimiter • Yet easy for routers to process because: • No more Checksum Calculations • Fragment Free, auto PMTUD • Broadcast free • Introduction of Anycast(one to one-of-many) • No need of Address Translation • Also easy for humans to use • Many ways to simply address writing • Mask will officially be written in “/” format e.g. /64

27. IPv6 – Addressing • Types of Addresses • Unicast (one-to-one) • Multicast (one-to-many) • Anycast (one-to-one-of-many)

28. IPv6 – Addressing Representation • All addresses are 128 bits • Write as sequence of eight sets of four hex digits (16 bits each) separated by colons • Leading zeros in group may be omitted • Contiguous all-zero groups may be replaced by “::” • Only one such group can be replaced

29. IPv6 – Addressing Representation • 3ffe:3700:0200:00ff:0000:0000:0000:0001 • can be written • 3ffe:3700:200:ff:0:0:0:1 • or • 3ffe:3700:200:ff::1

30. IPv6 – Addressing Representation … contd. • IPv6 born classless • Generally network and host portion can be equally divided into 64bits each. 64-bit Network 64-bit Host

31. IPv6 – Addressing Representation … contd. • Host portion can be manually set or automatically calculated (EUI-64) 64-bit Network 64-bit Host

32. IPv6 – Addressing Representation … contd. EUI-64 MAC Format 64-bit Network 64-bit Host ::0201:02FF:FE03:0405 N I C 00-01-02-03-04-05 Device

33. IPv6 – Addressing Representation … contd. • Link-local address • Unique on a subnet • Result of router discovery or neighbor discovery • High-order: FE80::/64 • Low-order: interface identifier • Site-local address • Unique to a “site” • High-order: FEC0::/48 • Low-order: interface identifier • What is a site?

34. IPv6 – Addressing Representation … contd. • Compatible IPv4 addresses • Of form ::a.b.c.d • Used by IPv6 hosts to communicate over automatic tunnels

35. IPv6 – Addressing Representation … contd. • Aggregatable global unicast address • Used in production IPv6 networks • Goal: minimize global routing table size From range 2000::/3

36. IPv6 – Addressing Representation … contd. Aggregatable global unicast address

37. IPv6 – Addressing Representation … contd.

38. IPv6 Direct and Indirect Communication

39. IPv6 – Communication Types Direct Communication “Between Same Networks” Indirect Communication “Between Different Networks”

40. IPv6 – Direct communication L2 L1 PC2 PC1 FEC0::1/64 FEC0::2/64

41. IPv6 – Indirect communication L2 L3 L2 L1 L1 L1 L2 PC2 PC1 G0/0 G0/1 FEC0::2:0:0:0:1/64 FEC0::1:0:0:0:2/64 FEC0::2:0:0:0:2/64 FEC0::1:0:0:0:1/64 FEC0::2/64 FEC0::1/64

42. IPv6 – ND Protocol vs IPv4 ARP IPv6 Neighbor Discovery protocol has the distinction of being the only truly new protocol created as part of the core of Internet Protocol version 6; there is no “NDv4” at all. Address Resolution Protocol: ND provides enhanced address resolution capabilities that are similar to the functions provided in IPv4 by ARP. Formalizing Of Router Discovery: In IPv4 the process of router discovery and solicitation was arguably an “afterthought”; ND formalizes this process and makes it part of the core of the TCP/IP protocol suite. Formalizing Of Address Resolution: In a similar manner, address resolution is handled in a superior way in ND. ND functions at layer three and is tightly tied to IP just like ICMP is. There is no more need for an “ambiguously-layered” protocol like ARP, whose implementation is very dependent on the underlying physical and data link layers.

43. IPv6 – ND Protocol vs IPv4 ARP Ability To Perform Functions Securely: ND operates at the network layer, so it can make use of the authentication and encryption capabilities of IPSec for tasks such as address resolution or router discovery. Autoconfiguration: In combination with features built into IPv6, ND allows many devices to automatically configure themselves even without the need for something like a DHCP server (though DHCPv6 does also exist.) Dynamic Router Selection: Devices use ND to detect if neighbors are reachable or not. If a device is using a router that stops being reachable it will detect this and ‘ automatically switch to another one.

44. IPv6 – ND Protocol vs IPv4 ARP Multicast-Based Address Resolution: Address resolution is performed using special multicast addresses instead of broadcasts, reducing unnecessary disruption of “innocent bystanders” when resolution messages must be sent.

45. IPv6 – Routing Protocols • Interior Gateway Protocols • RIPng • OSPFv3 • EIGRP • Exterior Gateway Protocols • MPBGPv4

46. IPv6 Migration Strategy

47. IPv6 Migration – HW/SW Upgradation • Hardware • End Systems • Network • Software • Operating System • Internetwork Operating System • Applications and Services

48. Types of Transition Mechanisms • Dual Stacks • IPv4/IPv6 coexistence on one device • Tunnels • For tunneling IPv6 across IPv4 clouds • Later, for tunneling IPv4 across IPv6 clouds • IPv6 <-> IPv6 and IPv4 <-> IPv4 • Translators • IPv6 <-> IPv4

49. Dual Stacks Network, Transport, and Application layers do not necessarily interact without further modification or translation IPv6 Applications IPv4 Applications TCP/UDPv6 TCP/UDPv4 IPv6 IPv4 0x0800 0x86dd Physical/Data Link

50. Dual Layers Applications TCP/UDP TCP/UDP IPv6 IPv4 0x0800 0x86dd Physical/Data Link