1 SIP IPv6/IPv4 transition solutions 通訊所 鍾國麟. 2 Outline IPV6 transition problem NAT-PT +...

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SIP IPv6/IPv4 transition solutions

通訊所 鍾國麟

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Outline

• IPV6 transition problem

• NAT-PT + SIP ALG

• TZI gateway

• 3GPP – IMS

• STUN-Based SIP Proxy

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IPV6 / IPV4 SIP 發生的問題

NAT-PT

IPv4 IPv6

IPv4 SIP_UA

IPv6 SIP_UAINVITE XXX@example.comWith IPv4 SDPA=140.123.1.1 … 看不懂 IPv4 位址

?? 140.123.1.1IP Mapping table

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NAT-PT + SIP ALG

DUAL-StackTranslator

IPv4 IPv6

SIP ALG

Media session Translator

IPv4 SIP UAIPv6 SIP UA

140.123.1.1 FF::1

INVITE XXX@example.comWith IPv4 SDPA=140.123.1.1 …

INVITE XXX@example.comWith IPv4 SDPA=FE::AA:1:1

IP Mapping tableRTP (ipv4) RTP (ipv6)

SIP_ALG Modify SIP/SDP Message

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TZI Gateway•

6WINIT Project; http://www.6winit.org• The TZI-Gateway is a application layer gatew

ay for signalling communication and media streams for use in heterogeneous IPv4/IPv6 networks

• Determine IP version of caller based on received INVITE message

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TZI Gateway 6WINIT Project; http://www.6winit.org

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3GPP-IMS Scenario

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3GPP-IMS Scenario– 3GPP IPv6 endpoint

• IPv6-only but IPv4-aware

– SIP Edge Proxy• Logical proxy entity• Dual-Stack• Manages pools of IPv6 and IPv4 addresses for one or multiple IPAP

Ms

– IP Address and Port Mapper (IPAPM)• IP translation (comparable to SIIT)• Manages address/port bindings• Controlled by edge proxy

– Control protocol• To be defined

– MEGACO, MIDCOM…

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• 目前 IPv6/IPv4 SIP solution– 需修改 NAT-PT , Gateway– SIP Proxy 和需 NAT-PT 合作 (IP Mapping)

• 利用 STUN 方法在 IPV6/IPV4 環境中穿透 NAT-PT 使得 SIP 可以通話。

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STUN - Simple Traversal of UDP Through NATs

NAT

Internet (Public Network)Private Network

192.168.1.1STUN server

IP mapping table

S: 192.168.1.1

Packet

140.123.1.xx

S:140.123.1.1

D:140.123.1.1 IP :140.123.1.1原來我對外的 IP 是 140.123.1.1

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STUN-based SIP Proxy

NAT-PT

IPv4 IPv6

IPv4 SIP_UA

IPv6 SIP_UAIP Mapping table

SIP ProxySIP Proxy

Dual stackRTP Relay

Dual stackRTP Relay

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• STUN-based SIP Proxy– Dual stack– Change SDP– RTP Relay– STUN

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IPV4 - SIPUA SIP Proxy 01 NAT-PT SIP Proxy 02 IPV6 - SIPUA

INVITE

STUN request

STUN response

INVITE

INVITE

OKSTUN request

STUN response

OKOK

RTP RTP RTP RTPRelay Relay

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IPV4 - SIPUA SIP Proxy 01 NAT-PT SIP Proxy 02 IPV6 - SIPUA

INVITE

INVITE ipv6@aaa.bb

SDP: 140.123.1.1

140.123.1.1 140.123.1.2FF::2 FF::1

Ipv6@aaa.bb

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IPV4 - SIPUA SIP Proxy 01 NAT-PT SIP Proxy 02 IPV6 - SIPUA

INVITE

140.123.1.1 140.123.1.2FF::2 FF::1

S:140.123.1.2

IP: AA::1

STUN request

STUN response S:140.123.1.2

S: AA::1

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IPV4 - SIPUA SIP Proxy 01 NAT-PT SIP Proxy 02 IPV6 - SIPUA

INVITE

140.123.1.1 140.123.1.2FF::2 FF::1

S:140.123.1.2

IP: AA::1

STUN request

STUN response

INVITE

INVITE ipv6@aaa.bb

SDP: AA::1

INVITE

INVITE ipv6@aaa.bbSDP: FF::2

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IPV4 - SIPUA SIP Proxy 01 NAT-PT SIP Proxy 02 IPV6 - SIPUA

INVITE

140.123.1.1 140.123.1.2FF::2 FF::1

S:140.123.1.2

IP: AA::1

STUN request

STUN response

INVITEINVITE ipv6@aaa.bbSDP: AA::1

INVITE

INVITE ipv6@aaa.bbSDP: FF::2

OK

200 OKSDP: FF::1

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IPV4 - SIPUA SIP Proxy 01 NAT-PT SIP Proxy 02 IPV6 - SIPUA

INVITE

140.123.1.1 140.123.1.2FF::2 FF::1

S:140.123.1.2

IP: AA::1

STUN request

STUN response

INVITEINVITE ipv6@aaa.bbSDP: AA::1

INVITE

INVITE ipv6@aaa.bbSDP: FF::2

OK200 OKSDP: FF::1

STUN request

STUN response

S:FF::2

IP: 163.1.1.1

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IPV4 - SIPUA SIP Proxy 01 NAT-PT SIP Proxy 02 IPV6 - SIPUA

INVITE

140.123.1.1 140.123.1.2FF::2 FF::1

S:140.123.1.2

IP: AA::1

STUN request

STUN response

INVITEINVITE ipv6@aaa.bbSDP: AA::1

INVITE

INVITE ipv6@aaa.bbSDP: FF::2

OK200 OKSDP: FF::1

STUN request

STUN response

S:FF::2

IP: 163.1.1.1

OKOK

200 OKSDP: 163.1.1.1

200 OKSDP: 140.123.1.2

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IPV4 - SIPUA SIP Proxy 01 NAT-PT SIP Proxy 02 IPV6 - SIPUA

INVITE

140.123.1.1 140.123.1.2FF::2 FF::1

S:140.123.1.2

IP: AA::1

STUN request

STUN response

INVITEINVITE ipv6@aaa.bbSDP: AA::1

INVITE

INVITE ipv6@aaa.bbSDP: FF::2

OK200 OKSDP: FF::1

STUN request

STUN response

S:FF::2

IP: 163.1.1.1

OKOK

200 OKSDP: 163.1.1.1

200 OKSDP: 140.123.1.2

ACK

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IPV4 - SIPUA SIP Proxy 01 NAT-PT SIP Proxy 02 IPV6 - SIPUA

INVITE

140.123.1.1 140.123.1.2FF::2 FF::1

S:140.123.1.2

IP: AA::1

STUN request

STUN response

INVITEINVITE ipv6@aaa.bbSDP: AA::1

INVITE

INVITE ipv6@aaa.bbSDP: FF::2

OK200 OKSDP: FF::1

STUN request

STUN response

S:FF::2

IP: 163.1.1.1

OKOK

200 OKSDP: 163.1.1.1

200 OKSDP: 140.123.1.2

ACK

RTP RTP RTP RTPRelay Relay

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結論• Modify Gateway

– NAT-PT+SIP ALG– TZI Gateway– 3G IMS

• 提出一個實驗性的架構在不修改 NAT-PT下，利用 SIP Proxy + STUN 使得 SIP 在 IPV6/IPV4 環境可使用

• NAT-PT 環境不容易架設