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Kamailio 4.1 (Crocodile Contributions)

Kamailio 4.1

Email: peter.dunkley@crocodilertc.netTwitter: @pdunkley

Kamailio 4.1 (Crocodile Contributions)

Peter Dunkley, Technical Director, Crocodile RCS LtdHugh Waite, Principal Engineer, Crocodile RCS Ltd

Email: hugh.waite@crocodile-rcs.com

What have we done?

● New modules– auth_ephemeral

– stun (previously a compile-time option in Kamailio core)

● Existing modules– registrar: outbound (RFC 5626) related enhancements

– outbound: outbound (RFC 5626) edge proxy enhancements

– tm: branch failure routes

– websocket: improvements to configuration and statistics

– Plus various other fixes and improvements

auth_ephemeral

Web Service

SIP Proxy

Calling UA

Called UA

SIP

SIP

RESTOAuth2

Shared secret – communication

link not required

You don’t have to create or manage accounts on the SIP Proxy/registrar

RFC 5626: SIP Outbound (1)

● Managing Client-Initiated Connections● Signalling NAT traversal

– Clients connect to edge proxies

– Edge proxies embed flow-tokens identifying the incoming connection in Record-Route: headers

– Clients send keep-alives to the edge proxies● Flow-Timer: header added to 200 OK response to REGISTER tells

clients how frequently to keep-alive● For connection-oriented transports (for example, SCTP and TCP) use

CRLF● For connection-less transports (for example, UDP) use STUN

– just load the stun module on the edge proxy

RFC 5626: SIP Outbound (2)

Edge Proxy

Edge Proxy

UA Registrar

Flow 2

Flow 1

Flow 2

Flow 1

RFC 5626: SIP Outbound (3)

● Client connection resilience– Clients may register multiple times (through different edge

proxies)

– If one “flow” fails you fall back to another

– Over to Hugh...

And for Kamailio 4.2...

● Per-message compression in WebSockets● Use database for auth_ephemeral secrets● TLS outbound connection validation● SIP DANE● ...

Crocodile WebRTC SDK and Network

www.crocodilertc.net