IPv6

INTERNET PROTOCOL VERSION

6

Presented By:Divye Kapoor

B.Tech (IDD) CSI

Acknowledgements

Akhil Langer

B. Tech. Computer Science

IIT Roorkee

IPv4 - RECAP

THE MAIN IPV6 HEADER

IPv4 – What’s Lost

GOALS

SUPPORT BILLIONS OF HOSTS

Larger Address Space (2128 hosts)

SIMPLIFY THE PROTOCOL, TO ALLOW ROUTERS TO PROCESS

PACKETS FASTER

No Checksum of the header – Integrity by Link Layer and Transport Layer checksums

No packet fragmentation – packet fragmentation is handled by issuing an ICMP msg

TTL has been changed to a Hop Limit so queing delays do not need to be computed

Rarely used IPv4 fields have been converted to options

PROVIDE BETTER SECURITY

IPsec support is mandatory for a conforming IPv6 implementation

Authentication, Non-Repudiation, Encryption

PAY MORE ATTENTION TO TYPE/QUALITY OF SERVICE, PARTICULARLY

FOR REAL TIME DATA

20 bit Flow Label field (QoS), 8 Bit Traffic Class (Priority)

Failure?

SCOPED MULTICASTING

Node Local, Link Local, Organizational, Global

MOBILE IPv6

No Triangular Routing via Routing Option Headers

EXTENSIBILITY AND CO-EXISTENCE WITH IPv4

Tunnelling

EASIER CONFIGURATION OF HOSTS

Stateless Address Autoconfiguration

GOALS

IPv6

DECEMBER 1988, IETF DESIGNATED IPv6 AS SUCCESSOR OF IPv4

BY THE PUBLICATION OF RFC 2460

PENETRATION STILL LESS THAN ONE PERCENT IN ANY COUNTRY

ADDRESS NOTATION

EIGHT GROUPS OF FOUR HEXADECIMAL DIGITS WITH COLONS BETWEEN THE

GROUPS

8000:0000:0000:0000:0123:4567:89AB:CDEF

THREE OPTIMIZATIONS

LEADING ZEROES WITHIN A GROUP OMITTED

ONE OR MORE GROUPS OF 16 ZERO BITS REPLACED BY A PAIR OF COLONS

8000::123:4567:89AB:CDEF

IPV4 ADDRESSES: PAIR OF COLONS AND AN OLD DOTTED DECIMAL NUMBER

::192.31.20.46

Feature: Scoped Multicasting

Flags

0 – Permanent Assignment by IANA

1 – Temporary Assignment

Advantage: STATELESS AUTOCONFIGURATION

ICMPv6 Router Discovery Messages

When a node first connects to a network, it issues a link-local multicast

router solicitation request.

Suitably configured routers respond with a router advertisement packet that

contains the network layer configuration parameters.

Alternatives: DHCPv6 or Static Host Configuration

Link Local Multicast is also used for Address Resolution (ARP)

EXTENSION HEADERS

Next Header == ?

Option Encoding for Hop By Hop & Destination Options

Special Case: Padding by 1

Option Encoding (cont…)

EXTENSION HEADERS

HOP-BY-HOP OPTIONS

EXTENSION HEADERS

The hop-by-hop extension header for large datagrams (Jumbograms)

1ST BYTE: WHAT KIND OF HEADER COME NEXT

2ND BYTE: LENGTH OF HEADER IN BYTES EXCLUDING THE FIRST 8 MANDATORY BYTES

3RD BYTE: TELLS THAT THIS OPTIONS DEFINES THE DATAGRAM SIZE (code 194)

4TH BYTE: SIZE IS A 4-BYTE NUMBER

LAST 4 BYTES: SIZE OF THE DATAGRAM

HOP-BY-HOP OPTIONS - Jumbograms

ROUTING HEADER LISTS ROUTER THAT MUST BE VISITED ON THE WAY TO THE DESTINATION

The extension header for routing

SEGMENTS LEFT

KEEPS TRACK OF HOW MANY OF THE ADDRESSES IN THE LIST HAVE NOT YET BEEN

VISITED

EXTENSION HEADERS

Type 0 Routing Header

FRAGMENT HEADER

EXTENSION HEADERS

DESTINATION OPTIONS FIELDS THAT NEED ONLY BE INTERPRETED AT THE DESTINATION HOST

NO CURRENT USE DEFINED

AUTHENTICATION HEADER PROVIDES A MECHANISM FOR RECEIVER TO MAKE SURE WHO SENT IT

ENCRYPTED SECURITY PAYLOAD USES CRYPTOGRAPHIC TECHNIQUES TO ENCRIPTS CONTENS OF PACKET TO

ENSURE ONLY THE INTENDED RECIPIENT CAN READ IT (IPsec features)

EXTENSION HEADERS

EXTENSION HEADERS

For Mobile IP – Proposed Header

Most goals are reasonably met.

Large scope for extension of the protocol

Mobile IP is still not officially supported by the IPv6 standard

CONCLUSION

REFERENCES

[RFC 2460] Deering, S. and R. Hinden, "Internet Protocol, Version 6, (IPv6) Specification",

December 1998. URL: http://www.ietf.org/rfc/rfc2460.txt

[RFC 3775] Johnson, D., Perkins C., Arkko J., “Mobility Support in IPv6”, June 2004. URL:

http://tools.ietf.org/html/rfc3775

Tanenbaum, Andrew S., Computer Networks, Fourth Edition, Chapter 5, The Network

Layer

URLs: htttp://en.wikipedia.org/wiki/IPv6, http://en.wikipedia.org/wiki/Mobile_IPv6

Thank You