1. IPv6:What, Why and How? Gihan DiasUniversity of MoratuwaWorld IPv6 Launch - 6/6/2012

2. What is an IP Address? 3. An IP address is a number used to identify a computer on a networkEvery computer on the net must have an IP address phone TVrefrigeratorlight 4. How many IP addressesdo we have?The current version of IP (IPv4) has about 4 billion addressesand about the same number of devicesSo we are running out of IPv4 addresses 5. The Asia Pacific Network Information Centre(APNIC) has reached the last block ofInternet Protocol version 4 (IPv4) addressesin its available pool.The remaining IPv4 space will be rationedto network operators to be used as essentialconnectivity with next-generation IPv6addresses.From this day onwards, IPv6 is mandatoryfor building new Internet networks andservices. - APNIC Director General Paul Wilson 6. What do we do? 7. Use IP version 6 (IPv6) 8. IPv6IPv6 is the successor to IPv4Defined in 1996over 15 years agouses 128-bit addressesmore than enough for any conceivable purpose 9. IPv6 SupportIPv6 is supported by all operatingsystemsWindowsLinuxOS/X, iOSAndroid, etc.Supported by all router / switch manufacturersCisco, Juniper, etc. 10. butIPv6 is hardly used today 11. Why? 12. Why is IPv6 not in use?Not supported by some low-end devicesLimitations in early support by WindowsXP, etc.Some applications dont support itThe Main Reason? I dont need to use it 13. Why Dont we Need IPv6? 14. NAT 15. What is NAT?Network Address TranslationComputers in an organisation use private IP addressese.g. beginning with 192.168.A NAT translates these addresses intoone or more public IP addresses100s of computers can use one public IPaddress 16. NAT: Network Address Translationrest of local network Internet (e.g., home network) 10.0.0/2410.0.0.110.0.0.4 10.0.0.2138.76.29.710.0.0.3All datagrams leaving localDatagrams with source or destination in this networkave same single source NAT IP address: 138.76.29.7,different source port numbers have 10.0.0/24 address for source, destination (as usual) 17. Problems with NATBreaks the core Internet concept of"one device, one address"Devices cant talk directly to one-anotherNo inbound servicesSome applications wont worke.g. IPsec, WINS 18. Main Problem with NATServers cant use NATthey need to be accessible from outsideNeed a public IP address for each serveror some kind of address sharingSo if you have lots of servers, you need lots of IP addresseswhere do you get them from? 19. Advantage of NATDevices cant be reached from outsideBetter securityis it?It is quite easy for hackers to get to NATTed machines via e-mail, web, etc.NAT provides only marginal security 20. Current SituationNo need for panicISPs in Sri Lanka have enough IPv4s tolast for another couple of years 21. NowOnly one or two addresses per customerso what if you want to run five servers?ADSL customers will have to share IPs3G customers dont get a public IP even now 22. from TodayMajor providers (Google, Facebook, etc.) will be on IPv6.and many othersmajor local sites to follow soonHuge numbers of clients starting from China and Japan) will be on IPv6They need to access youYou need to access them 23. What are my Options? 24. Do NothingUse NAT for my clientsneed one public IPUse available public IPv4 for serversmay need to share addressesbeg your ISP for addressesbuy addresses 25. Do Nothing (cont.)Need gateway to access v6 Internetwho provides it?Need gateway for v6 clients to access your serverswho provides it?No direct device-to-device communicationmay miss out on new services 26. Dual StackRun both v4 and v6 on your computersManagement is complicatedPerformance and Security issues 27. v6-only NetworkNeed gateway to connect to v4 worldNAT64Servers still need public IPv4 addressesMay be best solution for a new networksome applications may still not work 28. Dual Stack Servers and v4 ClientsOnly a small number of servers, so easierto manage dual stackYour services are available to the entireInternetClients go through NAT64still cant use device-to-device services 29. SummaryIPv6 is hereLaunched todaywont go awayCant ignore itmaybe you can ignore it for a yearBut will need to transition 30. Gihan Diasgihan@uom.lk