摘要:
A mechanism for describing dynamic display objects in a distributed computing environment is described. A service in a distributed computing environment may generate results data for a client in response to client requests. The service may provide schemas describing the presentation characteristics of results data. The schemas may include information for use in presenting the results data. The results data may include data elements, and the presentation schema may include presentation elements each including information describing the presentation characteristics of one or more of the data elements. The client may map data elements to corresponding presentation elements from the schema, and may use the element corresponding to a data element to present the data element. Using the dynamic display objects, display behavior may be altered without having to rebuild code.
摘要:
A service discovery protocol may allow clients to discover services on a proximity basis. A service device that provides one or more computing services may support a proximity communication link. A client device may form a proximity communication link with the service device. The client device may directly request from the service device a document that describes an interface to access a service provided by the service device. The service device may provide the document directly to the client device over proximity communication link. The document may include a service advertisement for the service, and the service advertisement may include a schema specifying an interface to at least a portion the service. The client device may use the information from the document to access the service. The client device may support a transport connection in addition to the proximity communication link, and the client device may make the document available to other devices over the transport connection. Thus, the client device may provide a bridge from the transport connection to the proximity communication link so that other devices from a distributed computing environment may access the service.
摘要:
A system and method for spawning new spaces in a distributed computing environment. A client may access a first space service at a first Internet address. The first space service may store one or more service advertisements and/or other content in a first space, and each of the service advertisements may include information which is usable to access and execute a corresponding service. The first space service may include a first XML schema which specifies one or more messages usable to invoke functions of the first space service. The creation of a second space may be requested such as by the client sending an appropriate request to an interface of the first space. The second space may be created to store the results of running a service. In response, a second space service with a second space may be created at a second Internet address. The second space service may include a second schema which includes at least the first schema, and the second schema may include additional functionality as well. The first and second space may share a common storage model, storage facility, and set of program code. The client may then access the second space at a second Internet address by sending to the second space at least one of the messages specified in the second schema.
摘要:
Embodiments of a mechanism for providing results gates to clients in the distributed computing environment to be used by the clients to access results generated by services on behalf of the clients. A client generates a request message for a service. The request message is generated by a client method gate. The service then generates results in response to the message. A results gate is generated for accessing the results. A gate on the client generates the results gate. The results are then accessed through the results gate. The results are structured as an object (e.g. Java object), and the results gate an object proxy for the results object. The results gate is returned to the process as results of the method call made by the process. In one embodiment, the results gate is a method gate and provides a method interface to the results.
摘要:
A service discovery protocol may allow clients in a distributed computing environment to search for services. Service providers (or a listener agent) may respond to search requests by publishing or providing corresponding service advertisements or URIs to corresponding service advertisements. When a service provider responds to a discovery search request (either directly or through a listener agent), the provider may choose to publish a protected or an un-protected (complete) advertisement. A protected advertisement may include the set of information necessary to obtain a complete advertisement. Publishing a protected advertisement may force the client to obtain a valid credential from an authentication service before receiving the complete un-protected advertisement from the service provider. A complete un-protected advertisement is needed to create a message endpoint for accessing the service. Forcing clients to obtain a valid credential before receiving an advertisement may provide an additional level of security for the service provider. The security credential that may need to be obtained to receive the complete advertisement may also be used to construct a message gate to communicate with the service where the gate embeds the security credential in each message to the service.
摘要:
Embodiments of message gates are described. A message gate is the message endpoint for a client or service in a distributed computing environment. A message gate may provide a secure endpoint that sends and receives type-safe messages. Gates may perform the sending and receiving of messages between clients and services using a protocol specified in a service advertisement. In one embodiment, the messages are eXtensible Markup Language (XML) messages. For a client, a message gate represents the authority to use some or all of a service's capabilities. Each capability may be expressed in terms of a message that may be sent to the service. Creation of a message gate may involve an authentication service that generates an authentication credential, and that may negotiate the desired level of security and the set of messages that may be passed between client and service. A message gate may perform verification of messages against a message schema to ensure that the messages are allowed. Message gates may embed the authentication credential in outgoing messages so that the receiving message gate may authenticate the message. Messages may also include information to allow the receiving gate to verify that the message has not been compromised prior to receipt.
摘要:
A system and method for searching for documents within spaces in a distributed computing environment are provided. A client sends a lookup message to a space which stores documents. The lookup message may specify desired characteristics, such as a name or partial XML schema, of the stored documents. The documents may include XML service advertisements and XML device advertisements as well as general-purpose XML documents. A set of zero or more documents which match the lookup message are discovered. In one embodiment, the lookup message may include a desired name. If the lookup message includes both a desired name and a desired schema, the set of discovered documents may include both discovered documents having a name that matches the desired name and discovered documents having a schema that matches the desired schema. If the lookup message includes neither a desired name nor a desired schema, the set of discovered documents may include substantially all the documents stored in the space. After the matching documents are found, the space may send a lookup response message to the client. For each discovered document, the lookup response message may include a name and an advertisement. Each advertisement may include information which is usable by the client to obtain the respective discovered document or access the resource (e.g., a service) that the document advertises. The advertisements and messages may be expressed in a data representation language such as XML.
摘要:
A mechanism for describing dynamic display objects in a distributed computing environment is described. A service in a distributed computing environment may generate results data for a client in response to client requests. The service may provide schemas describing the presentation characteristics of results data. The schemas may include information for use in presenting the results data. The results data may include data elements, and the presentation schema may include presentation elements each including information describing the presentation characteristics of one or more of the data elements. The client may map data elements to corresponding presentation elements from the schema, and may use the element corresponding to a data element to present the data element. Using the dynamic display objects, display behavior may be altered without having to rebuild code.
摘要:
A virtual machine (e.g. the Java Virtual Machine (JVM)) may include extensions for compiling objects (e.g. Java Objects) into data representation language (e.g. XML) representations of the objects, and for decompiling representations of objects into objects. The virtual machine may supply an API to the compilation/decompilation extensions. The compiler/decompiler API may accept an object as input, and output a data representation language representation of the object and all its referenced objects (the object graph) in a data stream. In addition, the compiler/decompiler API may accept a data stream, which includes a representation of the object and all its referenced objects (the object graph), and output the object (and all the objects in its object graph). In one embodiment, an intermediary format may be used to represent a data representation language document and may be dynamically processed to generate a class instance from the data representation language document.
摘要:
A system and method for providing an open network computing platform designed for peer-to-peer computing. The peer-to-peer platform may provide protocols for peer-to-peer services and applications that allow peers to discover each other, communicate with each other, and cooperate with each other to form peer groups. The protocols may include a peer membership protocol, a peer discovery protocol, a peer resolver protocol, a peer information protocol, a pipe binding protocol, and a peer endpoint protocol. Services and applications that participate in the protocols may be provided to deal with higher-level concepts. Advertisements may be used to publish peer resources. The peer-to-peer platform provides the ability to replicate information toward end users and may enable peers to find content that is closest to them. The peer-to-peer protocols and unique peer identifiers may allow peer nodes to move to different locations and access services and other content independent of network physical addresses.