1 SIP IPv6/IPv4 transition solutions 通訊所 鍾國麟

2 Outline IPV6 transition problem NAT-PT + SIP ALG TZI gateway 3GPP – IMS STUN-Based SIP Proxy

3 IPV6 / IPV4 SIP 發生的問題 NAT-PT IPv4 IPv6 IPv4 SIP_UA IPv6 SIP_UA INVITE With IPv4 SDP A= … 看不懂 IPv4 位址 ?? IP Mapping table

4 NAT-PT + SIP ALG DUAL-Stack Translator IPv4 IPv6 SIP ALG Media session Translator IPv4 SIP UA IPv6 SIP UA FF::1 INVITE With IPv4 SDP A= … INVITE With IPv4 SDP A=FE::AA:1:1 IP Mapping table RTP (ipv4)RTP (ipv6) SIP_ALG Modify SIP/SDP Message

5 TZI Gateway 6WINIT Project; The TZI-Gateway is a application layer gateway for signalling communication and media streams for use in heterogeneous IPv4/IPv6 networks Determine IP version of caller based on received INVITE message

6 TZI Gateway 6WINIT Project;

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16 3GPP-IMS Scenario

17 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 IPAPMs –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…

18 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。

19 STUN - Simple Traversal of UDP Through NATs NAT Internet (Public Network) Private Network STUN server IP mapping table S: Packet xx S: D: IP : 原來我對外的 IP 是

20 STUN-based SIP Proxy NAT-PT IPv4 IPv6 IPv4 SIP_UA IPv6 SIP_UA IP Mapping table SIP Proxy Dual stack RTP Relay Dual stack RTP Relay

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

22 IPV4 - SIPUASIP Proxy 01NAT-PTSIP Proxy 02IPV6 - SIPUA INVITE STUN request STUN response INVITE OK STUN request STUN response OK RTP Relay

23 IPV4 - SIPUASIP Proxy 01NAT-PTSIP Proxy 02IPV6 - SIPUA INVITE INVITE SDP: FF::2FF::1

24 IPV4 - SIPUASIP Proxy 01NAT-PTSIP Proxy 02IPV6 - SIPUA INVITE FF::2FF::1 S: IP: AA::1 STUN request STUN response S: S: AA::1

25 IPV4 - SIPUASIP Proxy 01NAT-PTSIP Proxy 02IPV6 - SIPUA INVITE FF::2FF::1 S: IP: AA::1 STUN request STUN response INVITE INVITE SDP: AA::1 INVITE INVITE SDP: FF::2

26 IPV4 - SIPUASIP Proxy 01NAT-PTSIP Proxy 02IPV6 - SIPUA INVITE FF::2FF::1 S: IP: AA::1 STUN request STUN response INVITE INVITE SDP: AA::1 INVITE INVITE SDP: FF::2 OK 200 OK SDP: FF::1

27 IPV4 - SIPUASIP Proxy 01NAT-PTSIP Proxy 02IPV6 - SIPUA INVITE FF::2FF::1 S: IP: AA::1 STUN request STUN response INVITE INVITE SDP: AA::1 INVITE INVITE SDP: FF::2 OK 200 OK SDP: FF::1 STUN request STUN response S:FF::2 IP:

28 IPV4 - SIPUASIP Proxy 01NAT-PTSIP Proxy 02IPV6 - SIPUA INVITE FF::2FF::1 S: IP: AA::1 STUN request STUN response INVITE INVITE SDP: AA::1 INVITE INVITE SDP: FF::2 OK 200 OK SDP: FF::1 STUN request STUN response S:FF::2 IP: OK 200 OK SDP: OK SDP:

29 IPV4 - SIPUASIP Proxy 01NAT-PTSIP Proxy 02IPV6 - SIPUA INVITE FF::2FF::1 S: IP: AA::1 STUN request STUN response INVITE INVITE SDP: AA::1 INVITE INVITE SDP: FF::2 OK 200 OK SDP: FF::1 STUN request STUN response S:FF::2 IP: OK 200 OK SDP: OK SDP: ACK

30 IPV4 - SIPUASIP Proxy 01NAT-PTSIP Proxy 02IPV6 - SIPUA INVITE FF::2FF::1 S: IP: AA::1 STUN request STUN response INVITE INVITE SDP: AA::1 INVITE INVITE SDP: FF::2 OK 200 OK SDP: FF::1 STUN request STUN response S:FF::2 IP: OK 200 OK SDP: OK SDP: ACK RTP Relay

31 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