1. 27th September 2016 Yanick.Pouffary@Compaq.Com
IPv6
27th September 2016

2. What is IPv4? Version 4 of the Internet Protocol 30+ Years Old
Incredibly successful
Today’s Internet runs over IPv4
IPv4 address is 32 bits
Many add-ons
Showing its age
Web, ftp,
telnet, etc.
application
presentation
session
transport
TCP, UDP
network
IPv4
link
Ethernet
physical

3. What is IPv6?
Version 6 of the Internet Protocol
Version 5 was allocated to the experimental Internet Stream Protocol (RFC 1190)
5+ years old
Poised for the continued growth and success of the Internet
IPv6 address is 128 bits
Web, ftp,
telnet, etc.
application
presentation
session
transport
TCP, UDP
network
IPv6
link
Ethernet
physical

4. IPv4: A Victim of Its Own Success
IPv4 addresses being consumed at an alarming rate, projections show:
Class B address space exhausted by 1994
All IPv4 address space exhausted between
Internet routing tables suffering explosive growth
Internet routing today is inefficient
Running out of Internet addresses
Stops Internet growth for existing users
Prevents use of the Internet for new users
Forces users to use Private Addresses

5. Interim Measures CIDR (Classless Inter-Domain Routing)
Eased routing table growth
Private addresses
Reduced pressure on address space, but…
Necessitated Network Address Translation, but…
Single point of failure
Network performance penalty
Breaks applications that rely on end-to-end IP addressing (FTP, DNS, others)
Use ALGs

6. More User Problems with IP today
System administration
Labor intensive, complex, slow, and error prone
Subscriber networks cannot be dynamically renumbered or configured
Security is optional; no single standard
No support for new protocols
Difficult to add to the base IPv4 technology
Extensive infrastructure require for mobility

7. Interim Measures Helped, But …
Address space consumption slowed, but Internet growth accelerated
“Everything to the Internet”
1B mobile users by 2005
1B Internet users by 2005
90% of all new mobile phones will have internet access by (Morgan Stanley Dean Witter, May 2000)
Projections of address space exhaustion by 2010
Pain Sooner (Europe and Asia)

9. … a longer term solution IP next generation (IPng)
1991: Work starts on next generation Internet protocols
More than 6 different proposals were developed
1993: IETF forms IPng Directorate
To select the new protocol by consensus
1995: IPv6 selected
Evolutionary (not revolutionary) step from IPv4
1996: 6Bone started
1998: IPv6 standardized
Today: Initial products and deployments

10. IPv6 Base Technology
Wins

11. Design Philosophy Recognizable yet simplified header format
Reduce common-case processing cost of packet handling
Keep bandwidth overhead low in spite of increased size of the address
Flexible and extensible support for option headers
Design optimised for 64-bit architecture
Headers are 64-bit aligned

12. IPv6 Header – Comparison with IPv4
bit
bit 8 16 24 31 4 12 16 24 31
Version
IHL
Service Type
Total Length
Version
Class
Flow Label
Identifier
Flags
Fragment Offset
Payload Length
Next Header
Hop Limit
Time to Live
Protocol
Header Checksum
32 bit Source Address
128 bit Source Address
32 bit Destination Address
Options and Padding
IPv4 Header 20 octets, 12 fields, including 3 flag bits
+ fixed max number of options
128 bit Destination Address
Changed
Removed
IPv6 Header 40 octets, 8 fields
+ Unlimited Chained Extension (options) Header

13. IPv6 Extension Headers
IP options have been moved to a set of optional Extension Headers
Extension Headers are chained together
IP options have been moved to a set of optional Extension Headers
Extension Headers are chained together
“Next Header” field indicated what follows next!
“Next Header” field value maps the IPv4 Protocol field (where applicable)
Ordering defined and must be processed in the order in which they appear
Most need to be processed at destination Host
Hop-by-Hop Options **
Jumbo Payload
Routing **
Fragmentation
Destination Options
Mobile Binding Update
Anycast Address Dynamic Update
Authentication (RFC 2402)
Encapsulating Security Payload (RFC 2406)
No Next Header
IPv6 Header
Next = TCP
TCP Header
Application Data
IPv6 Header
Next = Frag
TCP Header
Fragment Hdr
Next = Security
Security Hdr
Next = TCP
Data
Frag

14. IPv6 Header Performance Wins Layout
Fixed Size IPv6 Header
Unlike IPv4 - Options not limited at 40 bytes
Fewer fields in basic header
faster processing of basic packets
64 Bit Alignment Header/Options
Efficient option processing
Option fields processed only when present
Processing of most options limited performed only at destination

15. IPv6 Header Performance Wins Processing
Remove checksum from Network Layer
Datalinks are more reliable these days
Upper Layer checksums are now mandatory (for example, TCP, UDP, ICMPv6)
No fragmentation in the network
Reduce load on routers
Easier to implement in hardware
Easy for Layer 3 switching of IP
Minimum link MTU is 1280 bytes
From 68 in IPv4

17. Management Addressing Security
The power of IPv6
Management
Addressing
Security

18. Addressing Model (RFC 2373)
Addresses assigned to interfaces
No change from IPv4 model
Interfaces typically have multiple addresses
Subnets associated with single link
A link is a link-layer (layer 2) domain e.g. LAN
Multiple subnets on same link
IPv6 addresses have scope and lifetime
Link-Local
Site-Local
Global

19. IPv6 Unicast Address 3FFE:0301:DEC1:: 0A00:2BFF:FE36:701E
Address = prefix of n bits + interface ID of 128-n bits
Separate “who you are” from “where you are connected to”
Aggregatable Global Unicast Address format
n bits
128-n bits
prefix
Interface ID
Prefix Representation <prefix>::/<n-bits>
3FFE:0301:DEC1::
0A00:2BFF:FE36:701E

20. Management Addressing Security Other IPv6 goodies
The power of IPv6
Management
Addressing
Security
Other IPv6 goodies

21. Network Management Address Autoconfiguration Designed for hosts
It is assumed that routers are configured by some other means
Provides “Plug-and-Play” capability
Defines methods for obtaining routable address(es):
Link Local Address (No router or server required)
Stateless mechanism (Router advertisements provide prefix)
Stateful mechanism (Server provides address ( DHCP)

22. Network Management Renumbering IPv6 hosts is easy
Add a new prefix to the router
Reduce the lifetime of the old prefix
As nodes deprecate the old prefix, they begin using the new prefix for new connections
No network downtime
Renumbering IPv6 routers
New protocol: Router Renumbering (RFC 2894)
An end of ISP “lock in”!
Improved competition

23. Mobile IPv6 IPv6 Mobility is based on core features of IPv6
The base IPv6 was designed to support Mobility
Mobility is not an “Add-on” features
IPv6 Neighbor Discovery and Address Autoconfiguration allow hosts to operate in any location without any special support
No single point of failure (Home Agent)
More Scalable : Better Performance
Less traffic through Home Link
Less redirection / re-routing (Traffic Optimisation)

24. Management Addressing Security
The power of IPv6
Management
Addressing
Security

25. IPv6 Mandates IP Security
Security features are standardized and mandated
All implementations must offer them
Extensions to the IP protocol suite (RFC 2401)
Authentication (Packet signing)
Encryption (Data Confidentiality)
Operates at the IP layer
Invisible to applications
Protects all upper layer protocols
Protects both end-to-end and router-to-router (“secure gateway”) 9

26. Summary

27. A decade of design and testing
Core IETF specs have reached Draft Standard status No No
RFC Proposed
Standard
RFC
Draft
Standard
RFC
Internet
Standard
Yes
Yes
Yes
Internet
Draft
Technically
complete
Multiple
Interoperable
Implementations
Significant
Operational
Experience
6bone test bed
Today
1991
1996
1998
timeline

28. IPv6 key features and Advantages
Available TODAY in commercial products
Increased Address Space
Efficient and extensible IP datagram
Improved host and router discovery
Plug and Play
Enhancements for Quality of Service (QoS)
Improved Mobile IP support
IPsec mandated
Coexistence with IPv4
Extensibility of the Architecture

29. Conclusion Imagine what IPv6 can do for you!
IPv6 Solves many of the problems caused by the IPv4 success and more...
The technology you’ve been waiting for is here… Start deploying today!
Imagine what IPv6 can do for you!

30. Questions?