This document discusses problems with HTTP and HTML for mobile devices and proposes solutions. HTTP was designed for high-bandwidth, low-delay connections and results in large headers, uncompressed content transfers, and overhead from separate TCP connections for each page item. Caching is also often disabled on dynamic pages. HTML assumes desktop computers rather than mobile constraints. Solutions proposed include image scaling, content extraction, new protocols, push technologies, and enhanced caching through client and network proxies.

1. Support For Mobility

2. World wide web
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Problems encounters the web applications
used in a mobile and wireless environment.
Basic intro about HTTP
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It is a stateless , lightweight , application level
protocol for data transfer between servers and
clients.
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HTTP transaction consists of HTTP request
issued by the client and and HTTP response from
a server

3. HTTP
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It supported only simple caching mechanisms to
avoid unnecessary retransmission.
Caches may be located anywhere between
server and client.
Each client maintains a cache locally to
minimize delay when jumping back and forth on
web page.
Application must not cache page beyond
expiration.

4. HTTP problems
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Bandwidth and delay
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It is designed with high bandwidth/low delay
connections in mind.
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HTTP header is quite large and redundant.
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Server transfer content uncompressed.
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TCP connection is used for each item on web page,
huge overhead with each item.(three way handshack
and four way disconnection)
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Requires an additional request for DNS.

5. HTTP problems
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Caching
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It is usefull in many cases, often disabled by content
provider (number of clicks on a page).
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Present-day pages contain dynamic objects that
cannot be cached.
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Page often created dynamically depending on the
type of browser,client harware,client location etc.
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Can't merge static content with dynamic remainder
page.

6. HTML
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It is designed for standard desktop computers
connected witht a fixed wire.
Having high-resolution, mouse,sound system and
large hard disk.
Wireless devices having low-resolution, limited
user interference, low performance CPUs
Pages are degined for nice presentation of
content, not for efficient transfer of this content.

7. HTTP and HTML solutions
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Image scaling
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Scale down to fewer colors, lower resolution or just
title of picture. User decide to zoom or download.
Content transformtion
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Many application documents availabe is certain format
(pdf, post script etc.)
Convert and transfer.
Content extraction/semantic compression –
Headline or keyword extracted from a document

8. HTTP and HTML solutions
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Special language and protocols
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Replace HTML
Like introduction of Handheld Device Transport
Protocol (HDTP) and the Handheld Device Markup
Language (HDML)
Push technologies
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Instead of pulling content from server , the server
could push content to a client.
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Avoid overhead of connection on each object

9. System Architecture
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Integrated browser enhancement
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Integration of caching into web browser.
Does't perform pre-fatching of pages but
stores already transferred contents.
Additional application support browsing
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Pre-fatching of content, caching and
disconnected service
Client proxy as browser support
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Browser access the web server through the
client proxy.
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Proxy can perform pre-fetch and cache
content.

10. System Architecture
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Network proxy as browser support
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proxy support mobile client on
the network side
Further enhancement using ITCP.
Client and network proxy as
browser support
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Combined client and n/w proxy
Client and nerwork proxy with
special transmission protocol
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Client , n/w proxy with special
transmission protocol

11. Wireless Application
Protocol(version 1.x)
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WAP Forum was founded in June 1997 by
Ericsson, Motorola, Nokia and Unwired Planet
In 2002, the WAP forum together with open
mobile architecture forum formed open mobile
alliance.
Objective – To bring diverse internet content
and other data services to digital cellular
phones and other wireless, mobile terminals

12. Design Consideration
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Interoperable – alowing terminals and s/w from
different vendors to communicate with n/w from
different providers.
Scaleable – should scale with customers needs
and number of customers
Efficient – provision of QoS suited to the wirless
and mobile n/w
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Reliable
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Secure

13. Architecture