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IPv6 transition

Xing Li2014-01-22

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IPv4 depletion

• APNIC 3rd phase IPv4 allocation policy: one time /22• IPv4 address trading: $12/per transfer

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China Internet population

4

CERNET IPv6 transition experience

Translation IVI

Bi-direction Stateless Translation

IETF Behave WG

Dual-StackNFSCNET

IPv6 onlyCERNET2

• 200 universities• 2M subscribers

TunnelIPv6 over IPv4CERNET-6Bone

TunnelIPv4 over IPv6

IETF softwire WG

IPv4CERNET

• 2000 universities• 20M subscribers

1994 2000 2004 2005 20111998 2007

dIVI-PDDouble stateless

translationIETF Softwire WG

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Cost of transition

IPv4

IPv6

Dual stack

Translation cost

The ability of communication with the IPv4 Internet is the killer application of IPv6.

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RFCs of stateless translation• RFC6052

– IPv6 Addressing of IPv4/IPv6 Translators, 2010-10• RFC6144

– Framework for IPv4/IPv6 Translation, 2011-04• RFC6145

– IP/ICMP Translation Algorithm, 2011-04• RFC6219

– The China Education and Research Network (CERNET) IVI Translation Design and Deployment for the IPv4/IPv6 Coexistence and Transition, 2011-05

• RFC6791– Stateless Source Address Mapping for ICMPv6

Packets, 2012-11

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Stateless translation (IVI)

A subset of IPv6 addresses

IPv6IPv4

Real IPv6 hostReal IPv4 host mirrored IPv6 host mirrored IPv4 host

IVI

A subset of IPv6 addresses

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CERNET/CNGI-CERNET2

IPv4 IPv6

Stateless translation

IVI

dIVI

The IPv4Internet

The IPv6Internet

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Drafts of MAP• draft-ietf-softwire-map-t-04

– Mapping of Address and Port using Translation (MAP-T)

• draft-ietf-softwire-map-09– Mapping of Address and Port with Encapsulation

(MAP)• draft-ietf-softwire-map-dhcp-06

– DHCPv6 Options for configuration of SoftwireAddress and Port Mapped Clients

• draft-xli-softwire-map-testing-03– MAP Interoperability Testing Results

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Subscribers Providers Internet

IPv6

IPv6

IPv6

IPv4

Private IPv4

Private IPv4

IPv6

Private IPv4

IPv6

IPv4 i IPv6 Tunnel

IPv6

IPv6

IPv6-only

MAP

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1 000 000s of subscribers

:10s of MAP Rules

and no CGN

10 000s hostroutes per BNG

100s IGP prefixes

10s BGP prefixes

Stateless

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IPv6 Delegated Prefix (e.g., /56) 

IPv4 Address Port

Interface IDSubnet-ID64 (fixed)“EA Bits”

56-42 = 14

01010101 111000

/56

2001:0DB8:00 /42Mapping Domain Prefix

Size = 42 bits (provisioned)

0 42

> 0 XXXX12

6

0 6 16

10-6 = 4

130.67.1 /24

IPv4 Prefix 

24 bits (provisioned)

0 24

+01010101 111000

IPv4 Suffix

32-24 = 8 14-8 = 6

Port Set ID32

26=64 port setsper IPv4 Address

Ports 0-1023 skipped, each CPE gets 216/26 - 24 = 1008 ports

For this Example…

+

One IPv4 /24 serves 2(6+8) ≈ 16,384 (vs.≈256) subscribers

Stateless IPv4 address sharing

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IPv4

IPv6

Transport

Link

IPv4

Transport

Link

IPv4

Transport

Link

IPv6

Transport

Link

ORIPv4

Native IPv6 InfrastructureCE BR

MAP MAP

MAP-E MAP-T

Double translation vs. encapsulation

RFC2473 RFC6145

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Softwire 46 Container DHCPv6 Options

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MAP testing

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IVI dIVI

MAP-T

MAP

MAP-DHCP

MAP-T

LW4o6

MAP-E

464XLAT

DS-Lite

IVI

dIVI-PD

NAT64RFC2766

RFC6052, RFC6145

RFC6146

RFC6333 (14)

RFC6346

RFC2529RFC1933

RFC3056

RFC6877

RFC5969

RFC5214

RFC4380

IETF standard eveloution

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Comparisons

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2013 EANT

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Android 4.4

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OpenStack Summit 2014

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“IPv6-only” campus

IPv6 native IPv6 (prefer)IPv4 translation IPv6 (90% of the cases)IPv4 double translation (IPv4) (ALG issues)IPv4 encapsulation (IPv4) (corner cases)

transition

DIVI

IVI

IPv6-onlysubnet

DS subnet

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Windows 7 (IVI)

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Windows 7 (IVI with plugin)

24

iOS (IVI)

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Windows 7 (DIVI)

26

iOS (DIVI)

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Comparisons (DHCP)

IVIDHCP

DIVIDHCPv6

Total traffic

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New requirements

• Internet population– From 20% to 80%

• Mobile Internet – iPhone, iPad, PC, etc

• Cloud computing – Servers

• Internet of things– Everything connected

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BRIPv4/IPv6Core 

network

CE

CE

IPv6 access network

IPv6‐only server

IPv4

IPv6

DS

IPv4

IPv6

DS

AAADHCPv6

Broadband users

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IPv6-only cloud

xlatIPv4 Internet

IPv4VM

IP4v4VM

xlat xlat

IPv6 Internet

IPv6VM

IPv6VM

IPv6 IDC

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Connecting private networks

xlat xlat xlat

IPv6

Net 110.0.0.0/8

Net 210.0.0.0/8

Net 310.0.0.0/8

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IPv6

Internet of everything

IPv6

IPv4xlat

IPv4 users

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Lessons learned

• For existing IPv4 users– Dual stack where you

CAN– Tunneling where you

SHOULD– Translation where you

MUST

• For new Internet users and things– Translation where you

CAN– Tunneling where you

SHOULD– Dual stack where you

MUST