CPET 565 Mobile Computing Systems CPET 565 Mobile Computing Systems Mobile Device Connectivity Protocols Mobile Device Connectivity Protocols Lecture 14 Lecture 14 Hongli Luo Hongli Luo Indiana University-Purdue University Fort Wayne Indiana University-Purdue University Fort Wayne
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CPET 565 Mobile Computing Systems Mobile Device Connectivity Protocols Lecture 14 Hongli Luo Indiana University-Purdue University Fort Wayne.
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CPET 565 Mobile Computing SystemsCPET 565 Mobile Computing Systems
Mobile Device Connectivity ProtocolsMobile Device Connectivity Protocols
Lecture 14Lecture 14
Hongli Luo Hongli Luo Indiana University-Purdue University Fort WayneIndiana University-Purdue University Fort Wayne
Mobile Device Connectivity ProtocolsMobile Device Connectivity Protocols Wireless ProtocolsWireless Protocols
• WAP (Wireless Application Protocol)WAP (Wireless Application Protocol)• WML (Wireless Markup Language)WML (Wireless Markup Language)• BluetoothBluetooth• OBEX (Object Exchange)OBEX (Object Exchange)• WBXMLWBXML• Mobile Internet ProtocolsMobile Internet Protocols
Mobile Device Connectivity ProtocolsMobile Device Connectivity Protocols Limitations of Internet for wireless applications:Limitations of Internet for wireless applications:
• Low bandwidthLow bandwidth• High latencyHigh latency• Limited connection stabilityLimited connection stability• Small display sizeSmall display size• Limited input facilityLimited input facility• Limited memoryLimited memory• Limited processing powerLimited processing power
Mobile Device Connectivity ProtocolsMobile Device Connectivity Protocols Mobile software development considerationsMobile software development considerations
• Size of display limitedSize of display limited• Input device may be harder to manipulateInput device may be harder to manipulate• Sound may be limitedSound may be limited• Storage/processing ability could be slowerStorage/processing ability could be slower
• HTTP/HTML ->WAP/WMLHTTP/HTML ->WAP/WML• Allows accessing the web from a mobile phone or PDAAllows accessing the web from a mobile phone or PDA• WAP Forum, WAP Forum, http://www.wapforum.org/http://www.wapforum.org/• WAP 2.0, WAP 2.0,
• Integrates telephony services with browser technology, Integrates telephony services with browser technology, interactive Internet access for mobile handsetsinteractive Internet access for mobile handsets
Mobile Device Connectivity ProtocolsMobile Device Connectivity Protocols WAP InfrastructureWAP Infrastructure
• Mobile clientMobile client• A public land mobile network (GMS, etc)A public land mobile network (GMS, etc)• A public telephony networkA public telephony network• A WAP gatewayA WAP gateway
Transport layer protocol that sends and receives Transport layer protocol that sends and receives message via any available bearer network.message via any available bearer network.
• Wireless Control Message Protocol (WCMP)Wireless Control Message Protocol (WCMP)
WAP Architecture (client): Transport WAP Architecture (client): Transport Layer Security (WTLS)Layer Security (WTLS)• Optional security layerOptional security layer• Provides the secure transport service required Provides the secure transport service required
by many applications, such as e-commerceby many applications, such as e-commerce
reliability to the datagram service reliability to the datagram service provided by WDPprovided by WDP
Class 0 – unreliable one-way messages Class 0 – unreliable one-way messages without confirmation without confirmation
Class 1 – reliable one-way message without Class 1 – reliable one-way message without result messages (push Short Message result messages (push Short Message Services)Services)
Class 2 – reliable two-way request-response Class 2 – reliable two-way request-response messages (confirmation, result of a query) messages (confirmation, result of a query)
(WSP)(WSP)• Provides a lightweight session layer to allow Provides a lightweight session layer to allow
efficient exchange of data between efficient exchange of data between applicationsapplications
• Connection-Oriented services based on WTPConnection-Oriented services based on WTP• Connectionless services above datagram Connectionless services above datagram
transport servicestransport services• Supports HTTP 1.1 functionality and semantics Supports HTTP 1.1 functionality and semantics
in a binary-encoded formatin a binary-encoded format
WML (wireless Markup language)WML (wireless Markup language)• A Light markup language, optimized for use in A Light markup language, optimized for use in
handheld mobile terminalshandheld mobile terminals
WML ScriptWML Script• A lightweight scripting language, similar to A lightweight scripting language, similar to
JavaScriptJavaScript
From WAP white paper
Mobile Device Connectivity ProtocolsMobile Device Connectivity Protocols WAP GatewayWAP Gateway
• Protocol conversion Protocol conversion translates requests from a wireless protocol stack to translates requests from a wireless protocol stack to
WWW protocol (HTTP and TCP/IP)WWW protocol (HTTP and TCP/IP)
• Content encoders and decoders Content encoders and decoders translate WAP contents into a compact formattranslate WAP contents into a compact format
• User agent profile managementUser agent profile management describe client capabilities and personal preferencesdescribe client capabilities and personal preferences
• Caching proxyCaching proxy improve perceived performance and network improve perceived performance and network
utilizationutilization
WAP 2.0 FeaturesWAP 2.0 Features
Protocol layers for networks Protocol layers for networks supporting IPsupporting IP• Introduced in WAP 2.0Introduced in WAP 2.0• Motivated by the high-speed wireless Motivated by the high-speed wireless
network (e.g. 2.5G and 3G)network (e.g. 2.5G and 3G)• Protocol layersProtocol layers