Platform Architecture Platform Architecture

Mike ZintelMike ZintelDevelopment ManagerDevelopment Manager.NET Compact Framework.NET Compact FrameworkMicrosoft CorporationMicrosoft Corporation

AgendaAgenda

Design goalsDesign goals Internals of the platformInternals of the platform Key features that enable applicationsKey features that enable applications

Platform Design GoalsPlatform Design Goals

Portable & small .NET Common Portable & small .NET Common Language RuntimeLanguage Runtime

Leverage .NET toolsLeverage .NET tools Run .EXEs generated by .NET toolsRun .EXEs generated by .NET tools Cross-debug with VS.NETCross-debug with VS.NET

Peacefully co-exist with host OSPeacefully co-exist with host OS Scheduling, UI display surface & input, Scheduling, UI display surface & input,

resource contentionresource contention

Enable rich client Web Services appsEnable rich client Web Services apps GUI, local storage, networkingGUI, local storage, networking

.NET Terminology.NET Terminology

Execution Engine (EE)Execution Engine (EE) Common Language Runtime (CLR)Common Language Runtime (CLR) .NET Compact Framework.NET Compact Framework Programming FrameworksProgramming Frameworks

Class LibrariesClass Libraries

Native Code, Managed Code, ILNative Code, Managed Code, IL Common Language Runtime Common Language Runtime

ApplicationsApplications OEM ApplicationOEM Application

Developing A .NET AppDeveloping A .NET App

Testing on Window s

Target Platforms

.NET CF

.NET CF Execution Engine

.NET CF Class Libraries

CLR Application (.EXE & DLLs)

Win32 PAL

Windows

.NET CF Execution Engine

.NET CF Class Libraries

CLR Application (.EXE & DLLs)

Host O/S PAL & NSLs

Host Operating System

VS.NET

.NET Compilers

VS.NET Source Code

(Multiple Lang.) .NET CF Class Libraries

Edit Compile

Development

Run & Debug

Deploy

.NET CLR Features.NET CLR Features

Verifiable typesafe executionVerifiable typesafe execution No unsafe casts, no uninitialized variables, No unsafe casts, no uninitialized variables,

no out of bounds array indexing, no bad no out of bounds array indexing, no bad pointer mathpointer math

Garbage CollectionGarbage Collection No ref-counting, no leaksNo ref-counting, no leaks

JIT compilationJIT compilation Portable & fastPortable & fast

Common type systemCommon type system Call, inherit, and source-level debug across Call, inherit, and source-level debug across

different languagesdifferent languages

.NET API Design.NET API Design

Code and data are expressed as classesCode and data are expressed as classes Described in metadata, no .h or idl filesDescribed in metadata, no .h or idl files Inheritance can be used to extend a classInheritance can be used to extend a class

APIs work across languagesAPIs work across languages APIs are organized in namespaces with APIs are organized in namespaces with

strong naming conventionsstrong naming conventions Garbage Collection eliminates memory Garbage Collection eliminates memory

ownership issuesownership issues

.NET Error Handling.NET Error Handling

Error handling through exceptionsError handling through exceptions Not bools or HRESULTSNot bools or HRESULTS

Error handling is mandatoryError handling is mandatory Default isn’t to “muddle on”Default isn’t to “muddle on”

Descriptive exception messagesDescriptive exception messages Not cryptic HRESULTSNot cryptic HRESULTS

Language SupportLanguage Support

Plans for… Plans for… C#C# VB.NETVB.NET JScript (ECMAScript)JScript (ECMAScript)

Will deliver in staggered fashionWill deliver in staggered fashion Platform extensible to other languagesPlatform extensible to other languages VS.NET packages planned for C#, VBVS.NET packages planned for C#, VB

Different Types of Host O/SDifferent Types of Host O/S

Static address spaceStatic address space System image defined at manufacturing timeSystem image defined at manufacturing time pSOS, OSE, many custom O/SpSOS, OSE, many custom O/S Boot loader onlyBoot loader only No “application” loader or interactive shellNo “application” loader or interactive shell CLR adds app loader, makes system extensibleCLR adds app loader, makes system extensible

Apps run in “App Domains”Apps run in “App Domains”

Dynamic address spaceDynamic address space Boot loader & application loaderBoot loader & application loader Windows, UnixWindows, Unix Shell is provided by the O/SShell is provided by the O/S

System ArchitectureSystem Architecture

.NET Compact Framework

Host O/S

CLR Apps

Host O/S Apps

CLR

App Domain Host

CLR Apps

Host O/S Services Boot Loader Timers Hardware Drivers Threads Networking Sync Filesystems

Base Frameworks (Class Libs)

Platform Adaptation Layer (PAL)

Execution Engine App Domain Loader Instruction Engine/JIT Class Loader Garbage Collection Verifier P/Invoke Debugger

Platform Extension Frameworks

Native Support Libs (NSL)

managed

native

launch

Hardware

Execution EngineExecution Engine

Class loader, verifier, JIT, GC, exception Class loader, verifier, JIT, GC, exception handling, code access security, handling, code access security, debuggingdebugging

Provides hardware and O/S independent Provides hardware and O/S independent program executionprogram execution

No MMU required on the target CPUNo MMU required on the target CPU Garbage collection eliminates reference Garbage collection eliminates reference

counting and leakscounting and leaks JIT architecture for fast executionJIT architecture for fast execution

Supported Data TypesSupported Data TypesI1 (SByte) 8-bit 2's complement signed value

U1 (Boolean , Byte) 8-bit unsigned binary value

I2 (Int16) 16-bit 2's complement signed value

U2 (Uint16, Char) 16-bit unsigned binary value

I4 (Int32) 32-bit 2’s complement signed value

U4 (UInt32) 32-bit unsigned binary value

I8 (Int64) 64-bit 2’s complement signed value

U8 (UInt64) 64-bit unsigned binary value

R4 (Float) 32-bit IEEE 754 floating point value

R8 (Double) 64-bit IEEE 754 floating point value

O natural size object reference to managed memory

& natural size managed pointer (may point into managed memory)

* Natural size unmanaged pointer

Array  

String Unicode string class

Same as on the full .NET FrameworkSame as on the full .NET Framework

Native Code InteroperabilityNative Code Interoperability

IssuesIssues Calling conventionsCalling conventions Garbage collectionGarbage collection Security Vs. extensibilitySecurity Vs. extensibility

Platform Invoke (P/Invoke)Platform Invoke (P/Invoke) Managed Managed Native Native

IL_CallDelegateIL_CallDelegate Native Native Managed Managed

Inter-App Domain Message PassingInter-App Domain Message Passing

App DomainsApp Domains

Runtime construct that supports a Runtime construct that supports a running applicationrunning application Logical container of application threadsLogical container of application threads Provides memory isolationProvides memory isolation

Single execution engine instance can Single execution engine instance can support multiple app domainssupport multiple app domains

Execution engine ensures all resources Execution engine ensures all resources are released on app terminationare released on app termination

App Domain HostsApp Domain Hosts

Bootstrap the execution engineBootstrap the execution engine Written in C, call C APIs to start, pause Written in C, call C APIs to start, pause

and stop CLR applicationsand stop CLR applications Few constraints on execution modelsFew constraints on execution models

Loader hooks on Windows & Windows CELoader hooks on Windows & Windows CE Web server in ASP.NETWeb server in ASP.NET SQL uses CLR for stored proceduresSQL uses CLR for stored procedures Graphical shell or browser as shellGraphical shell or browser as shell

SecuritySecurity

Type-safetyType-safety On-device verification for software isolationOn-device verification for software isolation

Code Access Security with simple policyCode Access Security with simple policy Evidence determines access permission bucketsEvidence determines access permission buckets Evidence includes location, signing, banned listEvidence includes location, signing, banned list

Protocol for remote policy configurationProtocol for remote policy configuration Add/remove apps from banned listAdd/remove apps from banned list

User Identity/authenticationUser Identity/authentication Exposed through the PALExposed through the PAL

Network securityNetwork security SSL for Web Services, secure email, commerceSSL for Web Services, secure email, commerce

System qualitySystem quality

Remote Debugging, VS.NETRemote Debugging, VS.NET

File copy and run (F5)File copy and run (F5) Source code breakpointsSource code breakpoints Source code single-stepSource code single-step Stack traceStack trace Variable inspectionVariable inspection Thread suspend/resumeThread suspend/resume Data watchpointsData watchpoints Multiple device transportsMultiple device transports

Application InstallationApplication Installation

InstallInstall Copy files, perform configuration tasksCopy files, perform configuration tasks

UninstallUninstall Deletes filesDeletes files Dynamic dependency walk removes Dynamic dependency walk removes

orphaned shared componentsorphaned shared components Perform configuration tasksPerform configuration tasks

Shared class lib versioningShared class lib versioning ““Never break a functioning app”Never break a functioning app” Apps are written to specific class lib Apps are written to specific class lib

version or “latest”version or “latest”

GUI ArchitectureGUI Architecture

Two flavorsTwo flavors Generic – provides cross-OS portabilityGeneric – provides cross-OS portability

Drawing primitivesDrawing primitives Controls and FormsControls and Forms OEM-customizable look and feelOEM-customizable look and feel

Windows FormsWindows Forms Supersets generic functionalitySupersets generic functionality Available for Windows CE devicesAvailable for Windows CE devices Consistent with WinForms on .NET FrameworkConsistent with WinForms on .NET Framework Drag n’ drop UI designer in Visual StudioDrag n’ drop UI designer in Visual Studio

DrawingDrawing

Basic NetworkingBasic Networking

Platform Adaptation Layer (PAL)

CLR Apps

Hardware

Execution Engine

Host O/S

.NET Compact Framework

TCP/IP TCP, UDP

IrDA TinyTP

Bluetooth L2CAP

SMS

WAP, others

interfaces PPP/serial PPP/IrDA PPP/Bluetooth 802.xx

interfaces IrDA USB serial

HTTP Client Libs/Universal Listener XML Libs

Web Service Libs

Sockets API (name resolution, discovery, data) Connection Management API

Phone Book

Network ThreadingNetwork Threading

Apps can make synchronous (blocking) Apps can make synchronous (blocking) or asynchronous callsor asynchronous calls

Synchronous calls run on the caller’s Synchronous calls run on the caller’s threadthread

The system spins threads to support The system spins threads to support asynchronous callsasynchronous calls Threads terminate after a short no-use Threads terminate after a short no-use

timeouttimeout

Web Services & DevicesWeb Services & Devices

Clean, protocol level separation of Clean, protocol level separation of publishing and usagepublishing and usage Many producers, many consumersMany producers, many consumers

Separation of data from presentation Separation of data from presentation enables rich client applicationsenables rich client applications

Client applications can aggregate web Client applications can aggregate web services from multiple sourcesservices from multiple sources

Client applications can control Client applications can control “chunkiness” of transfers“chunkiness” of transfers

.NET CF can execute VS.NET generated .NET CF can execute VS.NET generated client proxy codeclient proxy code

PerformancePerformance

JIT compilationJIT compilation Focus on resource constrained devicesFocus on resource constrained devices Scalable to more capable devicesScalable to more capable devices TunableTunable Tradeoff different memory typesTradeoff different memory types

Memory UsageMemory Usage

CLR Apps .EXE and .DLLs

ROM

Execution Engine Code

RAM

App Domain Host Data

CLR Apps .EXE and .DLL

FLASH

R/O Filesystem

App Domain Host Code

Host O/S Code

R/W Filesystem

Host O/S Data

Execution Engine Data

CLR App Data

Object Data. JIT Cache. Released on app exit.

Questions?Questions?