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Reference will be made to the old API, allowing youto look up the information in the appropriate version of the SymbianOS Library.OTHER SOURCES OF INFORMATION9Information referring to future versions of Symbian OS – including thatwhich applies to v9.2 but not v9.1 – will be presented in a similarstyle.1.6 Example ApplicationsMost chapters have example applications to demonstrate the functionality we describe. You can download the source code from the Symbianwebsite: http://developer.symbian.com/main/academy/press. Whilst theexample apps have all been developed on S60 3rd edition or UIQ3 emulators and devices, the user interfaces provided by some apps use a simpletext shell. This is in order to focus on developing the communicationsside of the application rather than designing a nice UI.1.7 Reading GuideWhilst we’ve tried to make each chapter stand alone, inevitably somechapters have dependencies on others in this book.
These are our suggestions for reading each chapter.You are reading Chapter 1 now, so that’s covered. We suggest thateveryone takes a look at Chapter 2 to understand the basics of the systemstructure.Chapter 3, covering ESOCK, is rather abstract – we suggest you readone of Chapters 4, 5 or 6 (Bluetooth, IrDA, TCP/IP) first, then go back andlook at chapter 3 to understand the basic framework.Chapter 7, Telephony, stands alone.Chapters 8 and 9 fit together well, as they cover the messaging functionality from two different angles.
The example set of MTMs in chapter 9use the example code in chapter 11 for some functionality.Chapter 10, OBEX, requires some understanding of the material covered in chapters 4 and 5 – this is clearly indicated in the text.Chapter 11, HTTP, refers to the RConnection API, which is explainedin chapter 6.The example in Chapter 12, OMA Device Management, manipulatessettings for the example app in Chapter 6, so it’s worth having a look atthe application to see which settings need to be managed remotely.1.8 Other Sources of InformationSeveral times in this book we refer to the Symbian OS Library (formerly the Symbian OS Developer Library). This is available online at10INTRODUCTIONhttp://developer.symbian.com/main/oslibrary, and is also integrated intothe documentation that comes with S60 and UIQ SDKs.Information on specific UI platforms, as well as additional examplecode for Symbian OS, is available from the appropriate developer websitewww.forum.nokia.com or http://developer.uiq.com.1.9 The History of Symbian OS CommunicationsTo finish up this chapter we’ll give you some background on the development of the communications functionality in Symbian OS, and take aquick glance at how it has evolved over time – starting from the initialimplementation by Psion.The initial history of Symbian OS communications is closely tiedto that of the Psion Series 5 organizer – one of the original palmtopcomputers.
In 1997, Psion PLC released the original Series 5 organizer – arevolutionary 32-bit, ARM-based PDA. This was a follow on from their16-bit Series 3 organizer, itself a popular product in UK and some partsof Europe in the early 1990s. A major strength of the Series 5 wasan in-built suite of PIM applications. The other was an increasinglystrong suite of communications-related functionality added during theproduct’s lifetime.
The initial device contained an infrared port to beaminformation between devices over IrDA (but not using IrOBEX, whichwasn’t standardized in time for the initial Series 5) as well as a serial portfor connecting to PCs and modems. To access this functionality two of thecomponents still in use today were first introduced – c32 (more recentlyreferred to as the serial server) and ESOCK, which provides the SymbianOS socket API.Released after the original organizer as an installable software component, the Message Suite added a messaging subsystem with POP3, SMTPand fax capabilities to the device.In 1999, the follow up to the original Series 5 was released – the Series5mx.
This increased the amount of RAM and ROM in the device, providingspace for more functionality. OBEX was added to replace the originalPsion-proprietary IR transfer protocol – providing standards-based objecttransfer to other (non-Psion) devices. Also included was a new messagingarchitecture – the same as the one as you see today – designed to allowextension of the messaging functionality of the device using aftermarketplug-ins called Message Type Modules (MTMs), the first of which was anIMAP4 implementation.Later came a web browser from Opera Software AB.
By this time, thePsion organizer was sporting as much communications functionality assome PCs, all in a much smaller format and running off two AA batteries.In 1998, Symbian Ltd was formed – a joint venture between Ericsson,Motorola, Nokia and Psion. The staff of Psion Software Ltd transferredTHE HISTORY OF SYMBIAN OS COMMUNICATIONS11to Symbian Ltd, and started working to produce the first Symbian-basedmobile phone – the Ericsson R380. This was based off a Unicode versionof the ER5 release that powered the Series 5mx, and marked the startof the ‘one-box’ era in Symbian – the first time that the communicationssolution did not require a separate phone or modem in addition to theSymbian OS-based device, which had traditionally been referred to asthe ‘two-box’ model.One notable feature lacking from the R380 was the ability to installsoftware.
In 2001, the first open Symbian OS-based device was releasedby Nokia to replace their 9100-series communicator – the Nokia 9210.Again, this was a one-box design, with integrated GSM functionality.By this point, Symbian was working on adding both GPRS and Bluetooth functionality, which eventually shipped in Symbian OS v6.1. Thefirst product to take advantage of this was the Nokia 7650 – most notablefor being the first Symbian OS-based phone with an integrated camera.This feature meant it also included support for multimedia messaging(MMS) as part of the messaging functionality. As part of the introductionof Bluetooth, OBEX was extended to run over the new transport, and hadOBEX authentication added.
Symbian OS v6.1 also saw the release ofthe new IP-based connectivity solution for Symbian OS – replacing theold Psion Link Protocol (PLP) for connecting the device to PCs. As wellas serving as the basis for a series of Nokia phones, this version of the OSalso went into a series of sophisticated handsets released by Fujitsu forthe DoCoMo network in Japan.The first Symbian OS v7.0 device was the Sony-Ericsson P800, releasedin 2002.
New functionality in this release of Symbian OS included anHTTP stack, as well as the first release of the hybrid IPv4/IPv6 stack. TheETel multimode APIs were introduced, as was the first version of SyncML.Symbian OS v7.0s was first used in the Nokia 6600. Building onv7.0, the new release added advanced multihoming capabilities to theIP stack – allowing multiple simultaneous IP-based network connectionswith no risk of IP address range clashes or ambiguous routing situations.This functionality is still a step ahead of many operating systems today,many of which have problems when attached to multiple IP networks.This feature is especially important if there are any ambiguities betweenthe networks, such as address ranges that are operational in both networks – as is often the case where private IPv4 addresses are in use.Symbian OS v7.0s also introduced support for OBEX over USB, and theability for OBEX to receive objects to file rather than RAM.Symbian OS v8.0 saw major enhancements to the Bluetooth APIsfor link management, often referred to as the Bluetooth v2 architecture.OBEX gained APIs for user-defined headers and the ability to use doublebuffering when transferring objects.Symbian OS v8.1 saw the introduction of Bluetooth PAN profile,supporting the GN and U roles – although it was never shipped in a12INTRODUCTIONdevice until v9.1 when it appeared in UIQ3 devices.
Other changesincluded the SSL/TLS library being rewritten, providing new functionalitysuch as client authentication, and including new cipher suite supportincluding AES-based cipher suites. This version went into a series ofphones released by Fujitsu and Mitsubishi in the Japanese market, as wellas the Nokia N70, N72 and N90.Symbian OS v9.0 never shipped publicly – instead acting as an interimrelease to allow Symbian OS licensees to adopt the platform securitymodel.Symbian OS v9.1 has been an extremely popular version of SymbianOS – shipping in over 12 S60 and three UIQ device models so far. Itsaw the introduction of the multithreaded version of ESOCK, capable ofrunning each protocol module in its own thread to allow increased independence in scheduling of protocols.
Also introduced was support forthe Bluetooth A2DP profile – whilst the profile itself is not implementedby Symbian OS, much of the core technology is contained within theSymbian OS Bluetooth implementation. A new API on ESOCK, RSubConnection, was also introduced – initially to allow quality of service(QoS) functionality to be exposed.Features added in Symbian OS v9.2 are covered in the rest of thisbook.1.10SummaryIn this chapter we’ve summarized what information is contained inthis book and explained how it is structured.
We’ve also mentionedwhich topics and technologies are not in this book, and where togo to find information on them. You should have some idea of thelevel at which this book is pitched – we assume you have some basicSymbian OS development experience, and are in a position to be ableto create applications, but don’t expect you to know everything aboutcommunications technologies or their implementation in Symbian OS.The next chapter introduces the major communications subsystemsin Symbian OS, and shows how they fit together. If you’re interestedin a specific technology, and are happy about basic communicationsconcepts and the structure of communications in Symbian OS, feel freeto skip ahead to the appropriate chapter. Otherwise, read on for anintroduction to Symbian OS communications functionality.2OverviewIn this chapter we’ll present a brief overview of the different parts ofSymbian OS we’re going to talk about in this book.
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