The promise of e-business is coming true: both businesses and individuals are using the Web to buy products and services. Both want to extend the reach of e-business to new environments. Customers want to check accounts, access information, and make purchases with their cellular phones, pagers, and personal digital assistants (PDAs). Banks, airlines, and retailers are competing to provide the most ubiquitous, convenient service for their customers. Web applications designed to take advantage of the rich rendering capabilities of advanced desktop browsers on large displays do not generally render effectively on the small screens available on phones and PDAs. Some devices have little or no graphics capability, or they require different markup languages, such as Wireless Markup Language (WML), for text presentation. Transcoding is technology for adapting content to match constraints and preferences associated with specific environments. This paper compares and contrasts different approaches to content adaptation, including authoring different versions to accommodate different environments, using application server technology such as JavaServer pages TM (JSP TM) to create multiple versions of dynamic applications, and dynamically transcoding information generated by a single application. For dynamic transcoding, the paper describes several different transcoding methodologies employed by the IBM WebSphere TM Transcoding Publisher product, including HyperText Markup Language (HTML) simplification, Extensible Markup Language stylesheet selection and application, HTML conversion to WML, WML deck fragmentation, and image transcoding. The paper discusses how to decide whether transcoding should be performed at the content source or in a network intermediary. It also describes a means of identifying the device and network characteristics associated with a request and using that information to decide how to transcode the response. Finally, the paper discusses the need for new networking benchmarks to characterize the server load and performance characteristics for dynamic transcoding.

A user of computer networks has many choices for communication protocols. Current application programming interfaces (APls), such as sockets and CPI-C, run over some of these protocols. The trend toward global interorganizational networks is handicapped because programs written to one interface will often run on only one t>pe of transport network, and two programs must run on the same full protocol stack lo communicate. Ad hoc solutions exist, hut they are expensive and limited.The Multiprotocol rrangport Networking (XIPTh) architecture proposed in this paper is a general solution to providing interconnectivity far applications. The XIPTU architecture provides a protocol-independent system interface that includes most functions provided by existing transport protocols. As a result, the M P TN architecture decouples higher-layer protocols, application programming interfaces, and applications from protocols at the transport layer and helow. Using the MPTN architecture, existing and new applications can function unmodified over any transport supported under the ZlPTN interface. In addition, M P T N transport-layer gateways provide an end-to-end communication facility across a number of networks running different protocols. Therefore, a collection of networks running different protocols can serve as a single logical network.The paper describes four major aspects of the MPTN solution: a transport-layer protocol boundary, providing generic semantics at the transport layer so that the applications can he transport-independent; protocol compensation, adjusting for discrepancies between services required by generic transport layers and those provided by individual transport protocols; address mapping, resolving the difference u-hen the application and the protocol used to trarisport data use different address types; and general transport-level galeways, connecting networks running difkrent protocols. I This author is currently with Computer