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

Mobile Device Connectivity ProtocolsMobile Device Connectivity Protocols WAP (Wireless Application Protocol)WAP (Wireless Application Protocol)

• 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,

http://www.openmobilealliance.org/tech/affiliates/wahttp://www.openmobilealliance.org/tech/affiliates/wap/wapindex.html p/wapindex.html

• Integrates telephony services with browser technology, Integrates telephony services with browser technology, interactive Internet access for mobile handsetsinteractive Internet access for mobile handsets

• Typical WAP applicationsTypical WAP applications Over-the-air e-commerce transactions, online banking, Over-the-air e-commerce transactions, online banking,

information provisioning, and messaginginformation provisioning, and messaging• WAP 2.0 Technical White paper, WAP 2.0 Technical White paper,

www.www.wapwapforum.org/what/forum.org/what/WAPWAPWhite_Paper1.pdf White_Paper1.pdf

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

Protocol conversionProtocol conversion Content encodingContent encoding

• An IP networkAn IP network• A WAP application server A WAP application server

http://www.wiziq.com/tutorial/11611-wireless-markup-lang-WAP-WML

Mobile Device Connectivity ProtocolsMobile Device Connectivity Protocols WAP Architecture (client)WAP Architecture (client)

• Application Layer (WAE)Application Layer (WAE)• Session Layer (WSP)Session Layer (WSP)• Transaction Layer (WTP)Transaction Layer (WTP)• Security Layer (WTLS)Security Layer (WTLS)• Transport Layer (WDP)Transport Layer (WDP)• Bearers (Lowest Transport mechanism)Bearers (Lowest Transport mechanism)

Mobile Device Connectivity ProtocolsMobile Device Connectivity Protocols WAP Architecture (client): Bearers (Lowest WAP Architecture (client): Bearers (Lowest

Transport mechanism)Transport mechanism)• GSM (Global System for Mobile GSM (Global System for Mobile

Communications)Communications)• CDMACDMA• IPIP• UMTS (Universal Mobile Telecommunication UMTS (Universal Mobile Telecommunication

System)System)

Mobile Device Connectivity ProtocolsMobile Device Connectivity Protocols WAP Architecture (client): Transport Layer WAP Architecture (client): Transport Layer

(WDP)(WDP)• Wireless Datagram Protocol (WDP)Wireless Datagram Protocol (WDP)

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

Mobile Device Connectivity ProtocolsMobile Device Connectivity Protocols WAP Architecture (client): WAP Architecture (client):

Transaction Layer (WTP)Transaction Layer (WTP)• Provides transaction support, adding Provides transaction support, adding

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)

Mobile Device Connectivity ProtocolsMobile Device Connectivity Protocols WAP Architecture (client): Session Layer WAP Architecture (client): Session Layer

(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

Mobile Device Connectivity ProtocolsMobile Device Connectivity Protocols WAP Architecture (client): Application WAP Architecture (client): Application

Layer (WAE) environmentLayer (WAE) environment• Micro-browserMicro-browser• Displaying WML pagesDisplaying WML pages• Executing WML scriptExecuting WML script

WAP and InternetWAP and Internet InternetInternet

• HTTP/HTML/JavaScriptHTTP/HTML/JavaScript

WAPWAP• WAP/WML/WML ScriptWAP/WML/WML Script

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

Wireless Profiled HTTP (WP-HTTP)Wireless Profiled HTTP (WP-HTTP) Transport Layer Security (TLS)Transport Layer Security (TLS) Wireless Profiled TCP (WP-TCP)Wireless Profiled TCP (WP-TCP)

Mobile Device Connectivity ProtocolsMobile Device Connectivity Protocols WAP 2.0 WAP 2.0

http://www.openmobilealliance.org/tech/affiliates/wap/wapihttp://www.openmobilealliance.org/tech/affiliates/wap/wapindex.html ndex.html

• Architecture Architecture • Client IDClient ID• Client ProvisioningClient Provisioning• External Functional Interface (EFI)External Functional Interface (EFI)• General FormatsGeneral Formats• Multimedia Messaging Services (MMS)Multimedia Messaging Services (MMS)• PersistencePersistence• PushPush

Mobile Device Connectivity ProtocolsMobile Device Connectivity Protocols WAP 2.0WAP 2.0

• SynchronizationSynchronization• User Agent ProfileUser Agent Profile• Wireless Application EnvironmentWireless Application Environment• Wireless ProtocolsWireless Protocols• Wireless SecurityWireless Security• Wireless Telephony Application (WTA)Wireless Telephony Application (WTA)

Mobile Device Connectivity ProtocolsMobile Device Connectivity Protocols WAP ProfileWAP Profile

• Homepage: http://x.yy.xx.xyz/homepage.wml Homepage: http://x.yy.xx.xyz/homepage.wml • Connection typeConnection type• Connection securityConnection security• BearerBearer• Dial-up numberDial-up number• IP addressIP address• Authentication typeAuthentication type• Data call typeData call type• Data call speedData call speed• User nameUser name• PasswordPassword

From WAP white paper

Proxy can optimize the communication and may offer mobile service enhancements,

• such as location, privacy, and presence based services.

•It is necessary to offer Push functionality.