IPv4 to IPv6

Group A2-Roland Hollis- EJ Chambers-Rachit Gupta

Outline

Aspects of IP Version 4

What about Version 5?

Aspects of IP Version 6

Features of IPv6Auto-ConfigurationQos IP Security

VersVers HLENHLEN Service TypeService Type Total LengthTotal Length

IdentificationIdentification FlagsFlags Fragment OffsetFragment Offset

Time to LiveTime to Live ProtocolProtocol Header ChecksumHeader Checksum

Source IP addressSource IP address

Destination IP addressDestination IP address

IP Options (may be null)IP Options (may be null) PaddingPadding

IP Datagram Data (up to 65535 bytes)IP Datagram Data (up to 65535 bytes)

VERSVERS

IPv4 Header

IPv4 Addressing

232 Unique IP AddressesThis equates to be roughly 4 billion IP

AddressThis should be enough, but because of

network classes, many IP address are left unused

This spawned the concepts of Subnetting, CIDR and subnet 10

IPv4 AddressingCIDR – Classless Inter Domain RoutingCIDR and subnetting work together. Allow collapsing of contiguous class C

networks into a single routing table

Subnet 10Leaves the topology of your network up to

administrator.Gateways and Proxies are the intermediary

between the internet and your network

Other Methods

Other Methods include NATs – Network Address TranslationActs as a buffer between global internet

and your subnet. IP masquerading is a commonly used

technique for LinuxA modern NAT gateway must change the

Source address on every outgoing packet to be its single public address

IPv5 (?)

Why are we skipping from v4 to v6? IPv5 never existed!The version number “5” was assigned to

identify packets that carried experimental non-IP real-time stream protocol called SP

It was abandoned for RSVP

VersVers ClassClass Flow TableFlow Table

Payload LengthPayload Length Next headerNext header Hop LimitsHop Limits

Source Address 128 bits (4 x 32 bits)Source Address 128 bits (4 x 32 bits)

Destination Address 128 bits (4 x 32 bits)Destination Address 128 bits (4 x 32 bits)

VERSVERS

IPv6 Header

IPv6 Addressing

2128 IP Address340 Undecillion IP Addresses

So everyone including your cat and dog has one

Allows true end to end communicationA.k.a. No need for proxies and NAT

Multicasting is required, unlike in IPv4

Features of IPv6

Has a fixed header size, which then has a fixed packet size

Checksum value was removed since they are provided in data link and transport layers

NAT

Breaks end to end communication Routers monitor and

change the data

Breaks Bi-directional communication Hosts with global

address cannot initiate communication

IPv6 Address

FP – Format PrefixDenotes addressing format used

TLA – Top Level Aggregation Indications country or large carrier

R – Reserved for future useSome instances is combined with NLA

IPv6 Address Con’t

NLA – Next Level Aggregation Identifies a company or internet provider

SLA – Site Level AggregationAssigned by superior identity

Interface Id64 bit IEEE EUI-64 address of hardware

Ie the MAC

Auto configuration

Neighbor Discovery ProtocolDynamically determines information about

directly attached networksReplaces IPv4 ARP

Multicast vs. ARP’s broadcast

Plug and PlayStateful and Stateless auto configuration

Quality of Service

Different type of traffic be treated differently by intervention router in Internet.

IPv6 has “Flow Label” – Sender can request request special handling.

IPv6 header has an 8-bit traffic class field.

IP Security (IPSec)

A set of security services can be provided through use of traffic security protocolThe Authentication Header(AH)The Encapsulation Security Payload(ESP)

References

The Internet Protocol Version 6David C. Lee and Daniel L. Lough

The Next Generation of the Internet: Aspects of the Internet Protocol Version 6Daniel C. Lee, Daniel L. Lough, Scott Midkiff,

Nathaniel J. Davis, Phillip E. Benchoff

IPv6 – Future Approval NetworkingHui Huang, Jian Ma

Questions?

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