The Symbian OS (779886), страница 68
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SMS messaging re-architectedincluding support for Multimode (non-GSM) phone messagingrefactored from ETel◦ Smaller fixes in internet mail, fax client and scheduled send• Cryptography: support for x.509 parsing and ASM.1 library added• Connectivity: support for SyncML connectivity protocol added• MIDP JAVA ME introduced with fully compliant support for MIDletson Symbian OS; PersonalJava enhancements but JNI compatibilitymaintained• System Libraries◦ ECom (also known as ‘Magic’) Plug-in Framework introducedimplementing new plug-in architecture◦ StringPool API factored out of Uikon and re-engineered◦ Support for non ROM-based localization added◦ Support for Shift-JIS (Japanese) character set added• Kernel, Base Porting, and Build Tools◦ Emulator target build system migrated to Metrowerks CodeWarriorfrom Microsoft Visual C++◦ Added XScale processor support◦ New kits delivery model◦ New Backup and Shutdown server, USB support, MMC card support, power management improvements, performance improvements (speed and ROM footprint).324NOTES ON THE EVOLUTION OF SYMBIAN OSSymbian OS v7.0sSymbian OS v7.0s, announced in April 2003 at Symbian’s developerevent, repaired the fragmentation resulting from incompatibilities betweenSymbian OS v7.0 and v6.1 and the scale of the Symbian OS v7.0changes, which threatened to create permanent divergence betweenS60-based product lines from Nokia, and its licensees, and UIQ-basedproducts (for example, from Sony Ericsson and Motorola).
The SymbianOS v7.0s system architecture was based on a subsystem release model andrepresentation, retrospectively updated to the architecture representationbased on the system model.13.4Summary of Symbian OS v8 ReleasesAnnounced at 3GSM in February 2004 and reaching the market in phonessuch as the Nokia 6630, the Symbian OS v8 release was a significantincrement on Symbian OS v7. In particular, it marked the first appearanceof the real-time kernel.In large part, the feature set is common to both Symbian OS v8.0 andSymbian OS v8.1, except that Symbian OS v8.1 offers the option of thenew kernel.The main new functionality in Symbian OS v8 includes the following(by no means an exhaustive list):• CDMA telephony support• Multimedia Framework replacing Media Server• new connectivity, data synchronization and device management services architectures• new WAP stack architecture and implementation• OpenGL ES vector graphics support• new implementation of Certificate and Key Management• new App Installer architecture (preparing the way for Symbian OS v9Platform Security)• new content-access and content-handling frameworks, supportingpolicy-based content management, that is, DRM• new JAVA ME JSRS• USB-device class support• MMS support, including parsing of SMIL markup, and support forOBEX over Bluetooth and InfraredSUMMARY OF SYMBIAN OS V8 RELEASES325• Improved VCard and VCal conversion• New XML parsing frameworkSymbian OS v8.0Originally Symbian OS v8.0 was envisaged as the release which wouldintroduce the EKA2 kernel option for the first time.
However, in the event,only one Symbian OS v8.0 release was made, based on the original EKA1Symbian OS kernel.Symbian OS v8.0 marked a substantial increment on Symbian OS v7,with new features spanning most layers of the system:• Communications and telephony changes including the new communications framework based on the Comms Root Server and MBufs,first stage of CDMA telephony support, and Quality of Service (QoS)for GPRS• Bluetooth and short-link changes introducing new USB class supportproviding control for USB devices and Bluetooth stack changes tosupport new Java ME JSRs• New WAP short-stack WAP Messaging API, providing a limited functionality WAP stack and message API• OpenGL ES Framework introduced, as well as multi-client access toscreen, keyboard, and pointer or digitizer for GUI applications• New Multimedia Framework replacing Media Server, new ECamcamera API, Image Conversion Library and codec plug-ins, and lowlevel Media Device Framework providing low-level MIDI, video,speech recognition, and audio hardware-acceleration APIs• New implementations of Certificate and Key Management and secureapplication installation• Content-access and content-handling frameworks to support DRMcontent• New connectivity, data synchronization and device managementarchitectures• Java ME new JSRs including Mobile 3D 1.0 (JSR-184), Bluetooth 1.0(JSR082), Mobile Media API 1.1 (JSR135) and JTWI 1.0 (JSR185).• New VCard and VCal conversion support and new character encodings• New XML parsing framework, including XML Parsing Framework,WBXML Parser for WAP Binary XML, WBXML XML Parser Plugin• Messaging support for OBEX over Bluetooth and MMS messaging326NOTES ON THE EVOLUTION OF SYMBIAN OSSymbian OS v8.1aSymbian OS v8.1a is the Symbian OS v8.1 variant built on the originalEKA1 kernel, but otherwise sharing the same features as Symbian OSv8.1b:• ETel CDMA telephony extensions introduced support for CDMAnetworks, including CDMA SMS and WAP messaging support, andCDMA, Multimode, and SIM TSY reference plug-ins• Graphics support for multiple simultaneous display, multiple displaysizes and multiple display orientation• SyncML device management• Java ME upgrade to CLDC 1.1 from 1.0• New Comms Database compatibility.Symbian OS v8.1bSymbian OS v8.1b is the real-time EKA2 kernel release of Symbian OSv8.1.
This is the release, therefore, in which the EKA2 kernel becomesavailable for the first time.In Japan, Symbian OS v8.1b has been the platform for a wave of 3GDoCoMo FOMA phones (from Fujitsu, Mitsubishi and Sharp), in particularwith rich music and multimedia capabilities.13.5Summary of Symbian OS v9 ReleasesSymbian OS v9 is the platform for the latest ‘generation 3.x’ UIQ andNokia user interfaces, starting with UIQ 3 and S60 3rd Edition. It is alsothe release which introduces the new Platform Security architecture andcompletes the transition to the new real-time kernel architecture (firstintroduced as an option in Symbian OS v8.1; in Symbian OS v9, theoriginal EKA1 kernel is retired).Symbian OS v9 is the release with which Symbian has set its sights onthe high-volume, mid-range market and the Symbian OS v9 releases todate take incremental steps to improve the fit of Symbian OS with thatmarket, in particular in terms of performance and scalability (improvingcritical, basic performance and providing a cleaner architecture for porting to new hardware, support for single-core phone designs to reduce billof materials (BOM) cost, improved peripherals support, and other portingand tools improvements to help time-to-market and reduce developmentcost).
In keeping with these volume goals, it is also the platform on whichSymbian has made its ‘compatibility promise’, the promise of API stabilityfor all releases from Symbian OS v9 on.SUMMARY OF SYMBIAN OS V9 RELEASES327Compared with Symbian OS v8, the headline changes are the retiringof the EKA1 kernel architecture, in favor of the new, real-time kernel,and the introduction of platform security, providing a trusted applicationmodel.From a developer perspective, since the new kernel maintains userside API compatibility, the kernel changes have little application-levelimpact.
In contrast, platform-wide security has significant impact for alldevelopers, introducing a security-capability model to protect systemAPIs and data caging for all application data.The Symbian Signed signing and certification program grants capabilities (required to access protected APIs) to applications. Java ME MIDletsare also integrated into the security model. A free certification processis provided to freeware and shareware developers.
Experience to datesuggests that, for third-party developers, the more general certificationrequirements for robust and safe handling of extreme conditions (such asout-of-memory) are as much of an issue as the immediate requirementsof the security model.In other respects, Symbian OS v9 is very much an incremental updateto Symbian OS v8. There is little radical architectural change, but asignificant amount of re-engineering and improvement (in particular toimprove performance, with boot time and RAM usage the key targetareas, along with a set of user-oriented critical use-cases, for exampleaddition and deletion of multiple contacts).Symbian OS v9 also makes the transition from GCC to the ARMRVCT compiler, supporting the ARM ABI versions 1 and 2 and therefore promising tools interoperability for ABI-compliant tools (includingcompilers).Future Symbian OS v9 releases are likely to continue the focuson performance, including high-performance graphics and support forcontinued user interface evolution, improved suitability for the midrange, evolution of the build toolchain, and backwards compatibility,while introducing headline new technologies (likely candidates includelocation-based services).Symbian OS v9.0There is no productized Symbian OS v9.0 release, which instead servedas a baseline release for the integration of Platform Security on top of theEKA2 kernel.
All Symbian OS v9 ‘new features’ (as opposed to platformchanges) therefore appear in subsequent releases, from Symbian OS v9.1.Symbian OS v9.1The first phones based on Symbian OS v9.1 (which was announced inFebruary 2005) shipped during the first half of 2006. They included the328NOTES ON THE EVOLUTION OF SYMBIAN OSNokia N80 3G phone and Sony Ericsson P990, both with Wi-Fi andmultimegapixel cameras (3 and 2 megapixels respectively).For the enterprise market, device-provisioning enhancements andgroup-scheduling APIs are important additions.Headline features include:• Platform Security• Real-time EKA2 kernel, with support for a range of ARM CPU architectures and memory models• System Starter, a new policy-based mechanism for server startup• New Device Management and Client Provisioning services, includinga new Client Provisioning Framework• Broadcast Tuner APIs• Bluetooth Remote Control Framework• Improved Timezone support• Networking enhancements including RTP/RTCP support• Java ME MIDP 2.0 (JSR 118) and CLDC 1.1 (JSR 139), plus new MIDletsecurity policy support• Hardware reference platform incremented to TI OMAP H2.Symbian OS v9.2Symbian OS v9.2 continues performance improvements, supports severalnew locales and provides build-toolchain and porting improvements,while maintaining baseport compatibility, all of which can be seen assteps along the way to an improved mid-range offering.New features include some important new APIs and technologies (theSIP Framework, for example).
The major platform features, however, arethose which it shares with Symbian OS v9.1: platform security and theEKA2 kernel architecture.Compared with Symbian OS v9.1, the key changes are:• New RTP/RTCP and SIP multimedia protocols, together with underlying networking support and communications architecture evolutionto support high data rates• New Hindi and Vietnamese and improved Japanese language andlocale support• Device management, messaging, email and multimedia enhancementsSUMMARY OF SYMBIAN OS V9 RELEASES329• Continued improvements in boot time, RAM usage, and range ofspecific performance use cases• Hardware reference platform incremented to ARMv6.Symbian OS v9.3At the time of writing, the latest release (announced in July 2006) isSymbian OS v9.3. Compared with Symbian OS v9.2, the key changesare:• additions to SIP protocols and continued evolution of the communications architecture• support for Wi-Fi wireless networking.Part 3Design Case StudiesThe case studies presented here provide an in-depth examination ofsignificant turning points in the evolution of Symbian OS or of significantaspects of the wider context in which the operating system continuesto evolve.
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