1. Presence and IM using sip
4/22/2017
SIP beyond VoIP
Presence and IM using sip

2. “Presence, the dial tone of the 21-st century”
Henry Sinnreich, “The Godfather” of SIP

3. Adrian Georgescu Founder and CEO of AG Projects
Co-chair of ISOC SIP WG in the Netherlands
Management board member of OpenSIPS Software Foundation
Adrian Georgescu

4. AG Projects Core Business
Delivery and Support of Scalable Turnkey SIP Infrastructures
Since 2002
AG Projects Core Business

5. Projects we are involved with
OpenSIPS
OpenXCAP
MSRP Relay
CDRTool
MediaProxy
SIP SIMPLE client SDK
Blink
Projects we are involved with

6. All successful rich communications clients to date implement IM and Presence as a main built-in feature even if VoIP is the money generating service.
When all money has been made from proprietary solutions for real-time communications, a global solution based on universally accepted standards will emerge to absorb the demand for Presence and IM
Why this IS relevant

7. The standards for real-time communications are being forged by Internet Engineering Task Force
IETF

8. IETF SIP SIMPLE Working Group
SIP for Instant Messaging and Presence Leveraging Extensions (SIMPLE) IETF WG produces interoperable standards for SIP, Instant Messaging and Presence
IETF SIP SIMPLE Working Group

9. SIP SIMPLE standards MSRP Protocol and its Relay extension
SUBSCRIBE, NOTIFY and PUBLISH SIP methods
XCAP Protocol for storage of end-user documents
SIP SIMPLE standards

10. Message Session Relay Protocol (MSRP) is a protocol for transmitting a series of related instant messages in the context of a session. Message sessions are treated like any other media stream when set up via a rendezvous or session creation protocol such as the Session Initiation Protocol (SIP). MSRP Sessions are defined in RFC 4975 and RFC 4976.
MSRP Protocol

11. Is reliable by using TCP transport and secure by using TLS
End-to-end delivery confirmation for each message
Works sequential, suitable for chat sessions
No limit for data size, allows chunking
Built-in NAT traversal capability
MSRP Properties

12. Session description for Instant Messaging
Content-Type: application/sdp
Content-Length: 303
v=0
o= IN IP
s=Blink (MacOSX)
c=IN IP
t=0 0
m=message 2855 TCP/TLS/MSRP *
a=path:msrps:// :2855/b2d10bb428210c0ec686;tcp
a=accept-types:message/cpim text/* application/im-iscomposing+xml
a=accept-wrapped-types:*
a=setup:active
Session description for Instant Messaging

13. Session Description for File Transfer
Content-Type: application/sdp
Content-Length: 408
v=0
o= IN IP
s=Blink (MacOSX)
c=IN IP
t=0 0
m=message 2855 TCP/TLS/MSRP *
a=path:msrps:// :2855/b0bd df628;tcp
a=sendonly
a=accept-types:*
a=accept-wrapped-types:*
a=setup:active
a=file-selector:name:"About Stacks.pdf" type:com.adobe.pdf size: hash:sha1:83:D4:BB:70:67:FE:D7:04:89:99:2F:14:40:F3:40:46:93:88:0B:33
Session Description for File Transfer

14. MSRP Methods AUTH – To reserve a session in a MSRP relay
SEND – To send messages (or chunks of them)
REPORT – For end-to-end delivery confirmation
MSRP Methods

15. MSRP AUTH Method SENDING:
:18: : : > :2855
MSRP cecb7a09dd77a505 AUTH
To-Path: msrps://ag-projects.com;tcp
From-Path: msrps:// :65310/60089caac481a5898a73;tcp
Authorization: Digest username=" ", nonce="KDiJ6dUltB241YpjU1XEKTEyODM4NDc0ODMuNTg3OjgwLjEwMS45Ni4yMA==", realm="ag-projects.com", qop="auth", cnonce="5546b6f e0f9c2af95ba2a", nc=" ", opaque="c1e58368ebe508df8d84b94e71f9b8de", response="79546d58ae501c977c5f4ce74bb4fdfc"
cecb7a09dd77a505$
RECEIVED:
:18: : :65310 < :2855
MSRP cecb7a09dd77a OK
To-Path: msrps:// :65310/60089caac481a5898a73;tcp
From-Path: msrps://ag-projects.com;tcp
Authentication-Info: cnonce="5546b6f e0f9c2af95ba2a", nc= , rspauth="d96211e21bbe0d489c3e3a1c215794f3", qop=auth
Use-Path: msrps://node03.dns-hosting.info:2855/KDiJ6dUltB241YpjU1XEKTEyODM4NDc0ODMuNTg3OjgwLjEwMS45Ni4yMA==;tcp
Expires: 600
MSRP AUTH Method

16. MSRP SEND method RECEIVED:
:18: : :65310 < :2855
MSRP OC26za431IPezi3SfKpgNIpt SEND
To-Path: msrps:// :65310/60089caac481a5898a73;tcp
://node03.dns-hosting.info:2855/KDiJ6dUltB241YpjU1XEKTEyODM4NDc0ODMuNTg3OjgwLjEwMS45Ni4yMA==;tcp msrps:// :2856/a80a757b57acee5bcd69;tcp
Byte-Range: 1-240/240
Message-ID: 837fda182d73143e
Content-Type: message/cpim
To: Adrian Georgescu
From:
DateTime: T08:18:
Content-Type: text/plain
Welcome to the room, Adrian Georgescu. You are the only participant in the room
OC26za431IPezi3SfKpgNIpt$
SENDING:
:18: : : > :2855
MSRP OC26za431IPezi3SfKpgNIpt 200 OK
To-Path: msrps://node03.dns-hosting.info:2855/KDiJ6dUltB241YpjU1XEKTEyODM4NDc0ODMuNTg3OjgwLjEwMS45Ni4yMA==;tcp
From-Path: msrps:// :65310/60089caac481a5898a73;tcp
MSRP SEND method

17. IM Architecture SIP Client that implements MSRP protocol
SIP Server, a standard SIP Proxy
MSRP Relay for NAT traversal
IM Architecture

18. IM Architecture
A standard SIP Proxy is used in combination with a MSRP Relay. The receiving end-point reserves a TCP port on the publicly reachable relay and offers it in its 200 OK answer to the calling end-point.

19. XCAP protocol (RFC 4825) allows a client to read, write, and modify application configuration data stored in XML format on a server by using HTTP protocol.
An XCAP server is used to store data like buddy lists and presence policy in combination with a SIP Presence server to provide a complete SIP SIMPLE server solution.
XCAP Protocol

20. Presence Rules – stores policy shared with the Presence Agent
Resource Lists – stores contact names and SIP addresses
RLS Services – stores contacts to which server can subscribe
Icon – stores user photo and makes it available for subscribers
PIDF Manipulation – stores presence information when off-line
XCAP documents

21. Correlating buddy lists with policy information is tough enough
Getting it right is the most complex part building a SIP client
OMA has defined how XCAP is used for Presence (yet more convoluted)
Implementation complexity an order of magnitude higher than a VoIP call
XCAP documents Usage

22. PUBLISH – SIP Extension for Event state Publication RFC3903
SUBSCRIBE/NOTIFY – SIP Event Notification RFC 3265
Event packages – Presence, Winfo, Xcap-diff
SIP Methods

23. Publish method PUBLISH sip:31208005169@ag-projects.com SIP/2.0
From: "Adrian Georgescu"
To: "Adrian Georgescu"
Call-ID: CXP.qcaQG.LYO1bY0gN-JH1u4hEBuy49
Event: presence
Expires: 600
Content-Type: application/pidf+xml
User-Agent: Blink (MacOSX)
Content-Length: 745
<?xml version='1.0' encoding='UTF-8'?>
<presence xmlns:rpid="urn:ietf:params:xml:ns:pidf:rpid" xmlns:dm="urn:ietf:params:xml:ns:pidf:data-model”
<tuple id="lkqpmdpo">
<status>
<basic>closed</basic>
</status>
<contact
<timestamp> T11:52:28+02:00</timestamp>
</tuple>
<dm:person id="exnktxob">
<dm:timestamp> T11:52:07+02:00</dm:timestamp>
</dm:person>
<dm:device id="erquznkp">
<dm:note xml:lang="en">Powered by Blink (MacOSX)</dm:note>
</dm:device>
</presence>
Publish method

24. Subscribe method SUBSCRIBE sip:31208005169@ag-projects.com SIP/2.0
Via: SIP/2.0/UDP :60131;rport;branch=z9hG4bKPjzeIfWP8Qwt7cexqnCTioMIif.PM3Zvml
From: "Adrian Georgescu"
To:
Contact:
Call-ID: nfJWHU.kiCqywvL6Qr5oWcFukyTgQ4Cx
CSeq: SUBSCRIBE
Event: presence
Expires: 600
Accept: application/pidf+xml
User-Agent: Blink (MacOSX)
Content-Length: 0
Subscribe method

25. Notify method NOTIFY sip:nvdaehwt@80.101.96.20:64137 SIP/2.0
Record-Route: <sip: ;lr;ftag= >
To:
From:
CSeq: 1 NOTIFY
Call-ID: Vb5aZkC5K5G3nQUZZJLQQd.19NXrnQgd
Content-Length: 1288
User-Agent: OpenSIPS (1.4.5-tls (i386/linux))
Event: presence
Contact:
Subscription-State: active;expires=600
Content-Type: application/pidf+xml
<?xml version="1.0" encoding="UTF-8"?> …
</presence>
Notify method

26. Presence Architecture
4/22/2017
SIP Client that implements Presence methods and XCAP
SIP Server that implements a Presence Agent
XCAP Server for document storage (policy and buddy lists)
Presence Architecture

27. Presence Architecture
A Presence Agent together with an XCAP server aggregates the presence information for all SIP devices that belong to a certain SIP address and allows subscriptions to this information based on end-user policy.

28. Presence Aggregation
Multiple devices can publish partial presence document aggregated by the Presence Agent

29. Watcher Info Event
Watcher info event is used for monitoring external parties that subscribed to our own presence. Based on this list we can build a policy that is uploaded into the Presence Agent using XCAP protocol.

30. RLS Services extension to Presence Event
Subscription to RLS services lowers the SIP traffic on the last mile. The SIP client subscribes to only one SIP URI that is expanded by the RLS server into a list. The server sends back consolidated NOTIFY messages.

31. XCAP Diff Event
Multiple clients can automatically synchronize their buddy lists and presence policy by subscribing to this Event. When an XCAP document is changed by one device, the others get notified and can fetch it again.

32. Subscribe for xcap-diff
SUBSCRIBE SIP/2.0.
From: "saghul"
To: "saghul"
Contact:
Call-ID: wnIA-6Qe1hiB3cxUN06JzxQRKjUe3UCT.
CSeq: 9073 SUBSCRIBE.
Event: xcap-diff.
User-Agent: Blink (Linux).
Content-Type: application/resource-lists+xml.
Content-Length:
<?xml version='1.0' encoding='UTF-8'?>
<rl:resource-lists xmlns:rl="urn:ietf:params:xml:ns:resource-lists" xmlns:agp-rl="urn:ag-projects:xml:ns:resource-lists"><rl:list><rl:entry uri="org.openxcap.dialog-rules/users/sip%3Asaghul_test%40sip2sip.info/index"/><rl:entry uri="pidf-manipulation/users/sip%3Asaghul_test%40sip2sip.info/index"/><rl:entry uri="org.openmobilealliance.pres-rules/users/sip%3Asaghul_test%40sip2sip.info/index"/><rl:entry uri="resource-lists/users/sip%3Asaghul_test%40sip2sip.info/index"/><rl:entry uri="rls-services/users/sip%3Asaghul_test%40sip2sip.info/index"/></rl:list></rl:resource-lists>
Subscribe for xcap-diff

33. Available SIP SIMPLE Software
OpenSIPS – SIP Presence Agent
OpenXCAP – XCAP Policy Server
MSRP Relay – NAT Traversal for IM and File Transfer based on MSRP
SIP SIMPLE client SDK – Client SDK for all the above
Blink – A GUI client built on top of SIP SIMPLE client SDK
Available SIP SIMPLE Software

34. The Presence Agent is the most important architectural component
Originally developed in OpenSER, now present in all SER variants
Software currently developed and supported by Voice System S.R.L.
Home site:
OpenSIPS

35. Openxcap XCAP server integrated with OpenSIPS Presence Agent
Developed and supported by AG Projects
Openxcap

36. MSRP Relay NAT Traversal solution integrated with OpenSIPS
Developed and supported by AG Projects
MSRP Relay

37. SIP SIMPLE client SDK is a Software Development Kit for development of Real Time Applications based on SIP and related protocols for media transport like Presence, Audio and Instant Messaging (IM). Other media types can be easily added by using an extensible high-level API.
Developed and supported by AG Projects
SIP SIMPLE client SDK

38. SIP SIMPLE client SDK - CLI
sip-subscribe-presence
sip-subscribe-rls
sip-subscribe-xcap-diff
sip-subscribe-winfo
sip-publish-presence
xcap-pres-rules
xcap-rls-services
SIP SIMPLE client SDK - CLI

39. Blink A state of the art, easy to use SIP client built on top of
SIP SIMPLE client SDK. Currently available for Mac, Linux and Windows.
Developed and supported by AG Projects
Blink