DOC PREVIEW
U of I CS 241 - Protocol Architecture The Common Language

This preview shows page 1-2-3-26-27-28 out of 28 pages.

Save
View full document
View full document
Premium Document
Do you want full access? Go Premium and unlock all 28 pages.
Access to all documents
Download any document
Ad free experience
View full document
Premium Document
Do you want full access? Go Premium and unlock all 28 pages.
Access to all documents
Download any document
Ad free experience
View full document
Premium Document
Do you want full access? Go Premium and unlock all 28 pages.
Access to all documents
Download any document
Ad free experience
View full document
Premium Document
Do you want full access? Go Premium and unlock all 28 pages.
Access to all documents
Download any document
Ad free experience
View full document
Premium Document
Do you want full access? Go Premium and unlock all 28 pages.
Access to all documents
Download any document
Ad free experience
View full document
Premium Document
Do you want full access? Go Premium and unlock all 28 pages.
Access to all documents
Download any document
Ad free experience
Premium Document
Do you want full access? Go Premium and unlock all 28 pages.
Access to all documents
Download any document
Ad free experience

Unformatted text preview:

Protocol Architecture The “Common Language”Need for ProtocolsNetwork ArchitectureProgramming the CommunicationThe Levels of AbstractionLayered Network ArchitectureService PrimitivesSlide 8Example: Sending a Letter(Un-)Acknowledged ServiceProtocol ArchitecturesOSI Reference ModelOSI LayersOSI Layers and EncapsulationOSI Model in a Switched Communication NetworkA Tour of the OSI LayersSlide 17Slide 18Slide 19Slide 20Slide 21Slide 22TCP/IP Protocol SuiteExample: File TransferEncapsulation in the TCP/IP SuiteSlide 26Comparison of OSI Model and TCP/IP SuiteQuizProtocol ArchitectureThe “Common Language”Copyright by Jorg Liebeherr 98, 99Need for ProtocolsProtocols are a set of rules and conventions. By enforcing that communicating parties adhere to a common protocol, communication is made possible.Copyright by Jorg Liebeherr 98, 99Network ArchitectureA Network Architecture is a structured set of protocols that implement the exchange of information between computersCopyright by Jorg Liebeherr 98, 99Programming the CommunicationAny complex programming task is made simpler by using several levels of abstractionAbstraction hides the programming details of lower levelsCommunication tasks give rise to standard abstractionsCommittees such as the IETF (Internet Engineering Task Force) are in charge for standardizing the abstractions related to internet communicationCopyright by Jorg Liebeherr 98, 99The Levels of AbstractionMultiple levels of communication abstractions have been defined by standardization bodiesEach level is enforced by a corresponding protocolEach level uses the abstract services of the level belowAbstraction achieves separation of concernsA protocol needn’t know how the lower-level abstractions are implemented and what the higher level abstractions are.Copyright by Jorg Liebeherr 98, 99Layered Network ArchitectureIn a Layered Network Architecture, the services are grouped in a hierarchy of layers. A protocol of layer N uses only services of layer N-1.A protocol of layer N provides services only to layer N+1.ACEBD EBlayer 3layer 2layer 1not layered layeredACDCopyright by Jorg Liebeherr 98, 99Service PrimitivesN+1 LayerEntityN+1 LayerEntityN LayerEntityN LayerEntityN+1 Layer ProtocolX. Request X. Indication X. ResponseX. ConfirmAssume that some protocol implements service “X”.Copyright by Jorg Liebeherr 98, 99Service PrimitivesRecall: A layer N+1 protocol entity sees the lower layers only as an abstract service providerN+1 LayerEntityN+1 LayerEntityN+1 Layer ProtocolX. RequestX. IndicationX. Confirm Service ProviderX. ResponseCopyright by Jorg Liebeherr 98, 99Example: Sending a LetterBob’s mailboxBob AliceAlice’smailboxPostmanLogical flow of informationCopyright by Jorg Liebeherr 98, 99(Un-)Acknowledged ServiceUnconfirmed service: Acknowledged service: US MailL.Request L.IndicateL.IndicateL.Confirm US MailL.Request L.IndicateCopyright by Jorg Liebeherr 98, 99Protocol ArchitecturesThere are only few protocol architectures that are relevant today:OSI Reference ModelTCP/IP Protocols SuiteATM Protocol StackCopyright by Jorg Liebeherr 98, 99OSI Reference ModelThe OSI model defines seven layers:Layer 7: Application LayerLayer 6: Presentation LayerLayer 5: Session LayerLayer 4: Transport LayerLayer 3: Network LayerLayer 2: Data Link LayerLayer 1: Physical LayerInterconnection MediaCopyright by Jorg Liebeherr 98, 99OSI LayersPhysicalLayerPhysicalLayerPhysicalLayerPhysicalLayerData LinkLayerData LinkLayerData LinkLayerData LinkLayerNetworkLayerSessionLayerSessionLayerTransportLayerTransportLayerApplicationLayerApplic ationLayerPresentationLayerPresentationLayerNetworkLayerNetworkLayerNetworkLayerApplic ationHOSTNODEHOSTNODEApplicationCopyright by Jorg Liebeherr 98, 99OSI Layers and EncapsulationPhysicalLayerPhysicalLayerData LinkLayerData LinkLayerNetworkLayerSessionLayerSessionLayerTransportLayerTransportLayerApplicationLayerApplicationLayerPresentationLayerPresentationLayerNetworkLayerApplicationApplicationAHPHSHTHNHDHBitsDataAH DataPH AH DataSH PH AH DataTH SH PH AH DataNH TH SH PH AH DataDataApplicationDataHeader ofApplicationLayerCopyright by Jorg Liebeherr 98, 99OSI Model in a Switched Communication NetworkTransportSessionPresentationApplic ationTransportSessionPresentationApplicationPhysic alData LinkNetworkPhysicalData LinkNetworkPhysic alData LinkNetworkPhysicalData LinkNetworkPhysic alData LinkNetworkPhysicalData LinkNetworkStation (Host)Node (Router)Copyright by Jorg Liebeherr 98, 99A Tour of the OSI LayersPhysical Layer (Layer 1):Converts bits into electrical or optical signalsTransmits these signals over the hardware communication mediumExample: RS-232Copyright by Jorg Liebeherr 98, 99A Tour of the OSI LayersData Link Layer (Layer 2):Reliably transfers frames over a linkPerforms synchronization, error control, flow controlExample: PPPCopyright by Jorg Liebeherr 98, 99A Tour of the OSI LayersNetwork Layer (Layer 3):Moves packets inside the networkPerforms routing, addressing, switching, congestion controlExample: IPCopyright by Jorg Liebeherr 98, 99A Tour of the OSI LayersTransport Layer (Layer 4):Controls delivery of data between hostsConnection management, error control, flow control, multiplexing, TCP, UDP.Copyright by Jorg Liebeherr 98, 99A Tour of the OSI LayersSession Layer (Layer 5):Support the dialog between cooperating application programsSession management, synchronizationExample: RPCCopyright by Jorg Liebeherr 98, 99A Tour of the OSI LayersPresentation Layer (Layer 6):Data conversion into application formatEncryption/decryptionSecure socketsCopyright by Jorg Liebeherr 98, 99A Tour of the OSI LayersApplication Layer (Layer 7):Provides network access to application programsEverything is application specificExample: File Transfer, Electronic MailCopyright by Jorg Liebeherr 98, 99TCP/IP Protocol SuiteThe TCP/IP protocol suite was first defined in 1974The TCP/IP protocol suite is the protocol architecture of the InternetThe TCP/IP suite has four layers: Application, Transport, Internet, and Network Interface LayerApplicationLayerTransportLayerInternetNetworkInterfacetelnet, ftp, emailTCP, UDPIP, ICMP, IGMPDevice DriversCopyright by Jorg Liebeherr 98, 99Example: File TransferFTPprogramTCPIPEthernetDriverEthernetDriverEthernetDriverIPFTPprogramTCPIPEthernetDriverFTP protocolTCP protocolIP


View Full Document

U of I CS 241 - Protocol Architecture The Common Language

Documents in this Course
Process

Process

28 pages

Files

Files

37 pages

File I/O

File I/O

52 pages

C Basics

C Basics

69 pages

Memory

Memory

23 pages

Threads

Threads

14 pages

Lecture

Lecture

55 pages

C Basics

C Basics

24 pages

Signals

Signals

27 pages

Memory

Memory

45 pages

Threads

Threads

47 pages

Threads

Threads

28 pages

LECTURE

LECTURE

45 pages

Threads

Threads

30 pages

Threads

Threads

55 pages

Files

Files

37 pages

SIGNALS

SIGNALS

22 pages

Files

Files

37 pages

Threads

Threads

14 pages

Threads

Threads

13 pages

Load more
Download Protocol Architecture The Common Language
Our administrator received your request to download this document. We will send you the file to your email shortly.
Loading Unlocking...
Login

Join to view Protocol Architecture The Common Language and access 3M+ class-specific study document.

or
We will never post anything without your permission.
Don't have an account?
Sign Up

Join to view Protocol Architecture The Common Language 2 2 and access 3M+ class-specific study document.

or

By creating an account you agree to our Privacy Policy and Terms Of Use

Already a member?