Transcoding Middleware

Trans coding Middle ware is used to trans code one format of data to another format to suit the need of the client. For example, if we want to access a web site through a mobile phone supporting WAP, we need to trans code the HTML page to WML page so that the mobile phone can access it. Another example could be accessing a map from a PDA. The same map, which can be shown in a computer, needs to be reduced in size to fit the PDA screen. Technically trans coding is used for content adaptation to fit the need of the device. Content adaptation is also required to meet the network bandwidth needs. For example, some frames in a video clip need to be dropped for a low bandwidth network. Content adaptation used to be done through proprietary protocols. To allow interloper-ability, IETF has accepted the Internet Content Adaptation Protocol (ICAP). ICAP is now standardized and described in RFC3507. Internet Content Adaptation Protocol (ICAP) Popular web servers are required to deliver content to millions of users connected at ever-increasing bandwidths. Progressively, contents is being accessed through different devices and agents. A majority of these services have been designed keeping the desk-top user in mind. Some of them are also available for other types of protocols. For exam-ole, there are a few sites that offer contents in HTML and WML to service desktop and WA? phones. However, the model of centralized services that are responsible for all aspects of every client's request seems to be reaching the end of its useful life. ICAP, the Internet Content Adaptation Protocol, is a protocol aimed at providing simple object-based content vectoring for HTTP services. ICAP is a lightweight protocol to do transcoding on HTTP messages. This is similar to executing a 'remote procedure call' on a HTIP request. The protocol allows ICAP clients to pass HTIP messages 10 ICAP

Distributed Object and Components

An example of distributed objects and components is CORBA (Common Object Request Broker Architecture). CORBA is an open distributed object computing infrastructure being standardized by the Object Management Group (http://www.omg.org). CORBA simplifies many common network programming tasks used in a net centric application environment. These are object registration, object location, and activation; request demul-tiplexing; framing and error-handling; parameter marshaling and marshaling; and
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operation dispatching. CORBA is vendor-independent infrastructure. A CORBA-based program from any vendor on almost any computer, operating system, programming language and network, can inter operate with a CORBA-based program from the same or another vendor, on almost any other computer, operating system, programming language and network. COBRA is useful in many situations because of the easy way that CORBA integrates machines from so many vendors, with sizes ranging from mainframes through minis and desktops to hand-gelds and embedded systems. One of its most important, as well as the most frequent, uses is in servers that must handle a large number of clients, at high hit rates, with high reliability.

Distributed Object and Components

An example of distributed objects and components is CORBA (Common Object Request Broker Architecture). CORBA is an open distributed object computing infrastructure being standardized by the Object Management Group (http://www.omg.org). CORBA simplifies many common network programming tasks used in a netcentric application environment. These are object registration, object location, and activation; request demul-tiplexing; framing and error-handling; parameter marshalling and demarshalling; and
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operation dispatching. CORBA is vendor-independent infrastructure. A CORBA-based program from any vendor on almost any computer, operating system, programming language and network, can interoperate with a CORBA-based program from the same or another vendor, on almost any other computer, operating system, programming language and network. CORBA is useful in many situations because of the easy way that CORBA integrates machines from so many vendors, with sizes ranging from mainframes through minis and desktops to hand-helds and embedded systems. One of its most important, as well as the most frequent, uses is in servers that must handle a large number of clients, at high hit rates, with high reliability.

Distributed Object and Components

An example of distributed objects and components is CORBA (Common Object Request Broker Architecture). CORBA is an open distributed object computing infrastructure being standardized by the Object Management Group (http://www.omg.org). CORBA simplifies many common network programming tasks used in a netcentric application environment. These are object registration, object location, and activation; request demul-tiplexing; framing and error-handling; parameter marshalling and demarshalling; and
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operation dispatching. CORBA is vendor-independent infrastructure. A CORBA-based program from any vendor on almost any computer, operating system, programming language and network, can interoperate with a CORBA-based program from the same or another vendor, on almost any other computer, operating system, programming language and network. CORBA is useful in many situations because of the easy way that CORBA integrates machines from so many vendors, with sizes ranging from mainframes through minis and desktops to hand-helds and embedded systems. One of its most important, as well as the most frequent, uses is in servers that must handle a large number of clients, at high hit rates, with high reliability.

Distributed Object and Components

An example of distributed objects and components is CORBA (Common Object Request Broker Architecture). CORBA is an open distributed object computing infrastructure being standardized by the Object Management Group (http://www.omg.org). CORBA simplifies many common network programming tasks used in a netcentric application environment. These are object registration, object location, and activation; request demul-tiplexing; framing and error-handling; parameter marshalling and demarshalling; and
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operation dispatching. CORBA is vendor-independent infrastructure. A CORBA-based program from any vendor on almost any computer, operating system, programming language and network, can interoperate with a CORBA-based program from the same or another vendor, on almost any other computer, operating system, programming language and network. CORBA is useful in many situations because of the easy way that CORBA integrates machines from so many vendors, with sizes ranging from mainframes through minis and desktops to hand-helds and embedded systems. One of its most important, as well as the most frequent, uses is in servers that must handle a large number of clients, at high hit rates, with high reliability.