Wireless Application Protocol Henrik Saksela
Introduction • Motivation – ”WAP is positioned at the convergence of three rapidly evolving network technologies: wireless data, telephony, and the Internet” – ”The WAP specifications address mobile network characteristics and operator needs by adapting existing network technology to the special requirements of mass-market, hand- held wireless data devices and by introducing new technology where appropriate”
History • HDML by Unwired Planet – 1995-1997 • WAP Forum established – 1997 – Unwired Planet, Nokia, Ericsson, Motorola • WAP 1.0 – 1997 – WAP 1.1 – 1999 – WAP 1.2 – 1999 • WAP 2.0 – 2001 7110 - first WAP phone by Nokia
WAP 1.0, 1.1 • Design considerations – Limitations in mobile terminals • Inefficient CPU, little memory, small displays, numeric input pad – Limitations in the mobile network connections • Low bandwidth, high latency • Other requirements – Layered, scalable, extensible architecture – Support for as many wireless networks as possible • How to achieve this? – Tweak existing protocols / re-invent everything
WAP 1.1 Architecture Web Server Apache HTTP SSL WML, WMLScript, WTA, WAP Gateway Application Layer (WAE) Content formats TCP WAP stack Session Layer (WSP) ~HTTP/1.1 + state IP Transaction Layer (WTP) Transaction services Integrity, Privacy, Authentication, Security Layer (WTLS) DOS protection HTTP WSP Transport Layer (WDP) ~UDP WTP SSL Bearers: WTLS GSM, IS-136, CDMA, PHS, CDPD, PDC-P, iDEN, FLEX, etc… TCP WDP IP Bearer
Problems with first generation of WAP • Protocol criticism • Lack of adoption due to – Excessive re-invention in – High costs the name of wireless – Miserable usability – WAP not chosen on – No killer app technical merits – it was the only alternative • Personal experience – Contrary to claims, not – Everything cost money, open protocol – only WAP forum members allowed to same services available for participate in process free on regular internet – Specifications not – Lack of content published as RFC – Specifications subject to change without notice – Patent restrictions
WAP 2.0 – the second coming of WAP • WML dropped in favor of XHTML Basic extension, XHTML Mobile Profile • CSS Mobile Profile, subset of CSS 2 • Mobile profiles of HTTP, TLS, TCP replace first generation WAP stack • Additional services – MMS
WAP 2.0 Architecture Application Framework Service Security Multimedia Messaging Content Formats Discovery Services WAE/WTA User-Agent Push Crypto EFI Libraries Session Services Capability Negotiation Sync Provisioning Auth Cookies Push-OTA Protocol Framework Navigation Services Identity Transfer Discovery Hypermedia Streaming Message Transfer Transfer Service PKI Lookup Transport Services Datagrams Connections Secure Transport Services IPv4 SMS GHOST FLEX SDS Bearer Secure IPv6 USSD GUTS ReFLEX MPAK Bearer
WAP 2.0 adoption • WAP 2.0 overcame many of the problems in the earlier version – Partly because of general advances in technology: packet switching, more efficient devices, color displays • People use WAP features mobile internet usage in Britain without knowing it source: Mobile Data Association – MMS – Device provisioning • Still, mobile browsing isn’t experiencing phenomenal growth
Big in Japan • Wireless internet services have enjoyed enormous success in Japan • I-mode 46M subscribers as of Q3/06 • 29,5% of NTT DoCoMO ARPU • What differs from Europe / WAP? – I-mode ecosystem, business model • NTT DoCoMo – single company wields control over devices, infrastructure, services • Packet switched services from the beginning – Large single market – Smaller penetration of desktop internet services � expectations for handheld internet not preconceived – Success not isolated to I-mode – competitors have launched hugely successful WAP-based services based on the same concept
What does the future hold? • Where can WAP go from here? – Adoption of full W3C standards – complete mobile browser (á la S60 browser, Opera) • Competition – I-mode – Network-enabled J2ME applications • Opera Mini • Omat Lähdöt (HKL timetables) • Google Maps, GMail • What advantage does WAP have? – Over I-mode? None – Over J2ME? WAP proxy enables authentication � billing � content services! • Media services in line with MMS – Push e-mail • Is WAP dead? – Not yet, but it will complement rather than replace true mobile WWW browsing & J2ME- based services – In the long term, as handsets move closer to computers in functionality WAP will probably become irrelevant.
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