VoIP support on Qtopia. Vladimir Minenko, Ph.D.

Transcription

1 VoIP support on Qtopia Vladimir Minenko, Ph.D

2 TABLE OF CONTENTS 1 Introduction 2 Qtopia 3 Telephony in Qtopia 4 VoIP general things 5 Current status 6 What is coming 7 Resources and Links

3 INTRODUCTION Trolltech, products, community, customers Founded 1994, today >200 employees, Norway, Germany, USA, Australia, China Three main products: Qt, Jambi, Qtopia >5000 commercial customers world-wide Large open source community (KDE is a highlight) Several mobile customers, examples later 3

4 Qtopia Basics Provides application framework functionality Introduced in 2001 Targeted to embedded devices Based on Qt Dual licensing (GPL and commercial license) Funtionality depends on used package Qtopia Core Qt on embedded Qtopia Platform Core plus middleware Qtopia Phone Edition Platform plus applications 4

5 Qtopia QPE basics OS level Linux kernel 2.4 or higher. GCC version or higher. Footprint Standard build targets 32MB Flash ROM, 32MB RAM (including Linux) Hardware platform All processors supported by Linux with a C++ compiler and frame buffer driver Verified on x86 and ARM 9 & 11 chipsets, e.g. Marvell, Freescale, NXP, NEC, etc 5

6 Qtopia QPE basics Qtopia runs as an application on top of an OS Fully object oriented (C++), multitasking environment qpe always runs as a shell being a main UI An application is launched by qpe or even by another applications Differences to Qt programming are minimal Though some specifics are present, but hided from a developer by the system Hosting development environment is Linux. It includes emulator, build system, configure and sample device profiles 6

7 Qtopia System level architectural principles Qtopia, as a framework, is thought to be extended according the project targets Nevertheless a large set of features is implemented Qtopia uses Qt plug-ins implemented via shared libraries to extend functionality A new functionality is provided by services, which can be controlled via ICP A services provides a set of interfaces, which can be addressed to use a given functionality 7

8 Telephony in Qtopia Overview Supports GSM telephony (default) and VoIP Provides the ability to choose between either GSM or VoIP when making calls to a contact with both a phone number and VoIP identifier. An enhanced telephony integration mechanism based allows different modems and different phone-like transports Current VoIP integration uses this infrastructure Further features: split serial port ATC chat handling multiplexing An improved vendor plug-in mechanism allows vendors to directly inherit AT handlers and override individual functions. 8

9 Telephony Services and interfaces Services correspond to telephony handlers VoIP Modem <XYZ> Interfaces correspond to functionality offered by services SMS sending Presence <XYZ> 9

10 Telephony in Qtopia Overview Application One Interface Client QCop Modem Phone Server Other Service Application Two Interface Client QCop VoIP Stack The Phone Server is the only component that interacts directly with services such as GSM modem and VoIP. Applications use the interfaces to communicate with the Phone Server, e.g. QPhoneCallManager: make, break, hold and join phone calls; access existing calls; be notified of new calls. QSMSSender/Reader: send, store and read SMS. QPhoneBook: read and write access to SIM card phone books. 10

11 Telephony Example QPhoneCallManager* manager = new QPhoneCallManager(this); connect(manager, SIGNAL(newCall(QPhoneCall)), this, SLOT(newCall(QPhoneCall))); void ThisClass::newCall(const QPhoneCall& call) { if (call.state() == QPhoneCall::Incoming && call.calltype() == "Voice") { // process an incoming call } } 11

12 VoIP Feature vs. implementation VoIP voice over IP, is a functionality, which can be implemented differently Generally, it allows to transfer voice over IP connections and might include some additional services, e.g. presence There is no unified VoIP standard or architecture VoIP requires a server on the network, which manages sessions VoIP is not for free in many case, though the cost factor is lower than PSTN because runs on standard computer hardware and shares IP lines with data services 12

13 VoIP open and industry standards Open standards: Based on SIP (Session Initiation Protocol) from IETF ITU standard H.323 (the new version improved) Some most known industry and proprietary standards: Skype protocols (closed) Asterisk IAX protocol (open) The major implementation in Qtopia is SIP-based 13

14 VoIP SIP SIP - Session Initiation Protocol Requires a SIP server Establish and manage connection between call participants Presence and some more functionality Only being used for VoIP in Qtopia but can be used for other technologies 14

15 VoIP RTP and SDP RTP - Real-time Transport Protocol Transmit audio as packet data (IP) Uses codecs are agreed upon by both ends via SDP (Session Description Protocol) 15

16 VoIP VoIP stack Combined SIP, RTP and SDP implementations build up a VoIP stack Provided by 3 rd parties KPhone (KDE), Hellosoft, Radvision, M5T Also available with a chipset, e.g. from Broadcom Qtopia used an own implementation based on Open Source projects 16

17 VoIP Implementation VoIP User Interface Integration VoIP Framework Third Party VoIP Stack 17

18 VoIP Structure in Qtopia Qtopia Phone Server AT Handler Handler Framework Socket Adaptation Layer VoIP Configuration Application VoIP Stack 18

19 VoIP Integrating a VoIP stack VoIP Stack Adaptation Layer Separate process running along side Qtopia Register as a VoIP service (Qtopia will launch at correct time) When launched must connect to a particular Unix domain socket that Qtopia is listening on Send INIT message to announce self Specified message protocol DIAL, ACCEPT, HOLD, etc 19

20 VoIP Integrating a VoIP stack Configuration Application Reference implementation is a standard Qtopia application communicates to the VoIP stack through a common file 20

21 Current implementation Qtopia 4.2.x A sample SIP stack and VoIP user agent can be found in $QPEDIR/src/tools/sipagent Based on libdissipate2 library from Kphone (LGPL) which provides the SIP functionality Also implements audio transport via RTP, using the freely available G711u, G711a, GSM, and ilbc codecs. The Qtopia side of the protocol communication can be found in the source file $QPEDIR/src/libraries/qtopiaphone/qvoipli ne.cpp 21

22 Current implementation Qtopia 4.2.x Last updates for Greenphone are VoIP enabled Uses IP connection via the host (over USB cable) Also works via SDIO WiFi card Though not all Greenphones support this hardware-wise (request in the web shop) Tested with Go WiFi! P300 (via SD-to-miniSD adapter) 22

23 Current implementation Qtopia 4.3.x (not released yet) Improved 4.2.x implementations plus one more Based around the Asterisk iaxclient library Integrated for API testing if they are suitable for integrating a non-sip VoIP implementation if Qtopia could handle more than two telephony stacks (GSM, SIP, and Asterisk) active at the same time. Status of an unsupported example in Qtopia 4.3 Trolltech strongly recommends customer to integrate commercial 3 rd party stack 23

24 Current implementation Improvements needed Current VoIP in Qtopia implementation based on KPhone has a couple of drawbacks KPhone was made for desktop and has problems if GPRS/WiFi connection drops or IP changes Does not support some modern VoIP features RTP should be better integrated with Qtopia Media Server 24

25 Current implementation Fonav June 2007: Trolltech Acquires Fonav California startup VoIP solution for WiFi & Desk phones Based on Qtopia 2.2 Fonav solution Targeted at low cost connected devices Rich VoIP & Instant Messaging solution Complete user interface Technology Open standards: SIP, XMPP, RSS, POP3, SMTP Low footprint: fits into 32/16MB handsets Optimized performance for ARM9 150MHZ 25

26 Current implementation Qtopia plans Provide a reference integration of a commercial VoIP stack with modern features In the course of this works extend APIs Add infrastructure for better multimedia interworking Integrate Fonav technologies in the Qtopia product lines 26

27 Current implementation Qtopia based products Fonav VoIP handset platform Dual mode (GSM, SIP VoIP) phone by WNC (Wistron NeWeb Corp), available in France Sony mylo Skype phones Accton (under different brands) Panasonic KX-WP1050 Wi-Fi phone BTW, Qtopia is a certified Skype platform See also 27

28 RESOURCES AND LINKS VoIP sections docs Qtopia and Greenphone - incl. sections for Open Source Qtopia Component Matrix - Greenphone web shop - Your questions? 28