IPv6 The Big Move
- 1. IPv6 The Big Move: Transition and Coexistent Frenil V. Dand
- 2. Introduction • IPv6 (Internet Protocol version 6) is the successor to IPv4 • IPv4 is base on 32bits, with that its possible to express 4,294,967,296 different values. Over half a billion of those are unusable. Giving us 3.7 billion possible addresses • 5% of IPv4 are reaming • IPv4 will run out by end 2011 • IPv6 supports about 340 undecillion (1036) addresses 340,282,366,920,938,463,463,374,607,431,786,211,456
- 3. •IPv6 adoption has been slowed and IPv4 exhaustion has bee prolonged by NAT (Network Address Translation) http://www.ipv6forum.com/
- 4. Advantages of IPv6 • Trillions of times more addresses. • Easy to configure (Neighbor discovery and Stateless autoconfig) • Compatible with 3G and features that support greater mobility • Supports ad hoc networking • More efficient usage of broadband, via Jumbograms and Flow Label • Leaner Headers (six removed and one new filed). • More secure with mandatory IPSec • Better Quality of Service (QoS) • Allowing for many new possibilities
- 5. IPv6 Headers
- 6. How does IPv6 work? • New 128-bit addressing represented by eight 16 bit hex components divided by colons, X:X:X:X:X:X:X:X • Last 64 bits are used for interface ID • e.g. 2001:0DB8:C003:0001:0000:0000:0000:F00D • Can be represented in shorter format by removing leading zeros e.g. 2001:DB8:C003:1:0:0:0:F00D • Further reduction by removing consecutive fields of zeros using the double-colon :: option • Double-colon can be used only once, because multiple occurrences would lead to ambiguity • e.g. 2001:DB8:C003:1::F00D
- 7. • Addresses are organized in a hierarchical manner to facilitate: - Scaling - Aggregation - Routing • Aggregation is achieved by address prefix and the organization of addresses into two levels- public topology and interface identifier • Smaller routing tables allows for increase routing efficiency
- 8. • IPv6 supports three address types: - Unicast Addresses: one-to-one (global, link local, unique local, compatible) - Multicast Addresses: one-to-many (also replaces broadcast addresses) - Anycast Addressed: one-to-nearest (allocated from Unicast)
- 9. IPv6 Global Unicast Address Generic Division of Unicast Field Name Size (bits) Description Global Routing Prefix: The network Prefix “n” ID or prefix of the address, used for routing. Subnet Identifier: A number that Subnet ID “m” identifies a subnet within the site. Interface ID: The unique identifier for a particular interface (host or Interface ID “128-n-m” other device). It is unique within the specific prefix and subnet. • Unicast will be used for majority of the traffic • One-eighth of address is assigned to it •2001:0DB8:C003:0001:0000:0000:0000:F00D
- 10. IPv6 Multicast and Anycast • Multicasting allows for single device to send data to group of recipient • Format Prefix of 1111 1111 • Always begins with FF Four bits are reserved for Flags. Scope ID Currently, first 3 of them are set to zero (unused) (16 different values from 0 to 15) Last bit is Transient. Currently defined values (in decimal) Transient can be zero or one: 0 = Reserved If T set to Zero, then multicast address is well- 1 = Node-Local Scope known permanently assigned 2 = Link-Local Scope If T set to One, then multicast address is not 5 = Site-Local Scope permanently assigned 8 = Organization-Local Scope 14 = Global Scope 15 = Reserved
- 11. Unicast Multicast Anycast • Send • Send • Send • Send this to this to this to this to closest one every any member address member member of this of this of this group group group • Anycast addresses are new to IPv6 • Cross between unicast and multicast • Allows datagrams to be sent to whichever router in a group of equivalent router is closest
- 12. Autoconfiguration and Renumbering • By default IPv6 host can configure a link-local address for each interface • Router discovery allows host to determine addresses of routers, additional addresses, and other configuration parameters • Address autoconfiguration can only be performed on multicast-capable interfaces • 6 steps device takes for stateless autoconfiguration
- 13. 1. Link-Local Address Generation- device generates a link-local address 2. Link-Local Address Uniqueness Test- node tests to ensure the address in not duplicated 3. Link-Local Address Assignment- device assigns the link-local address to its IP interface 4. Router Contact- node next attempts to contact local router for more information on continuing the configuration 5. Router Direction- router provides direction to the node on how to proceed 6. Global Address Configuration- host will configure itself with its globally unique Internet address
- 14. IPv6 Transition and Coexistence • Very long and difficult process • IPv4 and IPv6 incompatible • Various technologies • Three categories : – Dual Stack – Tunneling – Translation
- 15. • Dual Stack is a network stack that supports both IPv4 and IPv6 while sharing most of the code • To work effectively must be implemented on all routers in network • Works by using two addressing schemes in parallel • Requires more resources
- 16. • Tunneling is technique which consists of encapsulating • Allows IPv6 packets over IPv4 networks • Require dual-stack at end of tunnel • Three main tunneling techiques: – IPv6 over IPv4 (6over4) – IPv6 to IPv4 (6to4) automatic tunneling – Tunnel Broker • Three step of tunneling are: – Encapsulation – Descapsulation – Tunnel management
- 17. • 6over4 – Embeds IPv4 in IPv6 – Not auto; needs network admin for end point • 6to4 automatic tunneling – Tunnel endpoint doesn’t require administrator – IPv4 embedded in the last 32 bits – IPv6 packets send over IPv4 network • IPv6 Tunnel Broker – 3rd party service or a vendor
- 18. • Teredo is extension of basic 6to4 – Provides IPv6 connectivity behind NAT – Uses 3rd party relay service – Vista and Windows 7 running Teredo – Easy for average Internet users • Intra-Site Automatic Tunnel Addressing Protocol (ISATAP) similar to 6over4 – Automatic encapsulation by using virtual IPv6 – Used in enterprise network
- 19. • IPv4/IPv6 Translation – Once considered as a last resort – Not simple as it sounds – Based on Stateless IP/ICMP and Network address translation – Only option of IPv6 transition that entirely remove IPv4 addresses. – Single-stack approach • 6rd – IPv6 Rapid Deployment – Big move help in residential consumer – Allows ISP to designate relay – Requires home hardware to support 6rd – Encapsulation of IPv6 inside IPv4 and send to ISP
- 20. Conclusion • Not a overnight process • Interoperability key • IPv6 is going to internet and world of communications to the next level • Japan, China and other countries in Asia-Pacific are already deploying and using IPv6 • 2008 Beijing Olympics was the widest use of IPv6 • Refrigerators can order groceries and taxis can detect rain and message to headquarters • And let’s not forget iPad, iPhone, and Android’s • DOD and Federal Government already running IPv6