Format negotiation for media remoting scenarios

Abstract

Format negotiation for media remoting involves at least one media data format. In an example embodiment, a media format negotiation for playing media data is begun between a server and a client. The media data format is transferred from the server to the client. A notification that indicates if an attempt at the client to construct a media topology responsive to the media data format was a success or a failure is transferred from the client to the server. Whether and/or how the media data is to be transferred from the server to the client may be impacted by the notification.

1 .- 20 . (canceled) 
     
     
         21 . A method for maintaining distributed cache coherency across multiple clients accessing a file or a shared resource, the method comprising:
 associating an oplock key with a first client, wherein the oplock key includes a file handle;   transmitting an oplock state request from the first client, the request indicating that the first client is locally caching one or more of: (i) write data, (ii) read data, and (iii) the file handle;   receiving the requested oplock state;   in response to determining that the first oplock state is broken, requesting a second oplock state; and   transitioning from the first oplock state to the second oplock state.   
     
     
         22 . The method of  claim 21 , wherein the oplock key is associated with a plurality of files. 
     
     
         23 . The method of  claim 21 , wherein the oplock key is generated by a protocol server. 
     
     
         24 . The method of  claim 21 , wherein determining that the first oplock state is broken comprises determining whether an open request associated with a file has the same oplock key as the first oplock state. 
     
     
         25 . The method of  claim 21 , wherein determining that the first oplock state is broken comprises determining whether a transition was made from the first oplock state to a state of lesser caching. 
     
     
         26 . The method of  claim 21 , further comprising sending an acknowledgement that the first oplock state is broken. 
     
     
         27 . The method of  claim 26 , further comprising sending an indication of a level at which the first oplock state is broken. 
     
     
         28 . A computer-readable storage medium encoding computer executable instructions that, when executed by at least one processor, performs a method for maintaining distributed cache coherency across multiple clients accessing a file or a shared resource, the method comprising:
 associating an oplock key with a first client, wherein the oplock key includes a file handle;   transmitting an oplock state request from the first client, the request indicating that the first client is locally caching one or more of: (i) write data, (ii) read data, and (iii) the file handle;   receiving the requested oplock state;   in response to determining that the first oplock state is broken, requesting a second oplock state; and   transitioning from the first oplock state to the second oplock state.   
     
     
         29 . The computer-readable storage medium of  claim 28 , wherein the oplock key is associated with a plurality of files. 
     
     
         30 . The computer-readable storage medium of  claim 28 , wherein the oplock key is generated by a protocol server. 
     
     
         31 . The computer-readable storage medium of  claim 28 , wherein determining that the first oplock state is broken comprises determining whether an open request associated with a file has the same oplock key as the first oplock state. 
     
     
         32 . The computer-readable storage medium of  claim 28 , wherein determining that the first oplock state is broken comprises determining whether a transition was made from the first oplock state to a state of lesser caching. 
     
     
         33 . The computer-readable storage medium of  claim 28 , further comprising sending an acknowledgement that the first oplock state is broken. 
     
     
         34 . The computer-readable storage medium of  claim 32 , further comprising sending an indication of a level at which the first oplock state is broken. 
     
     
         35 . A computer system comprising:
 one or more processors; and   a memory coupled to the one or more processors, the memory for storing instructions which, when executed by the one or more processors, cause the one or more processors to perform a method for maintaining distributed cache coherency across multiple clients accessing a file or a shared resource, the method comprising:
 associating an oplock key with a first client, wherein the oplock key includes a file handle; 
 transmitting an oplock state request from the first client, the request indicating that the first client is locally caching one or more of: (i) write data, (ii) read data, and (iii) the file handle; 
   receiving the requested oplock state;   in response to determining that the first oplock state is broken, requesting a second oplock state; and   transitioning from the first oplock state to the second oplock state.   
     
     
         36 . The system of  claim 35 , wherein the oplock key is associated with a plurality of files. 
     
     
         37 . The system of  claim 35 , wherein determining that the first oplock state is broken comprises determining whether an open request associated with a file has the same oplock key as the first oplock state. 
     
     
         38 . The system of  claim 35 , wherein determining that the first oplock state is broken comprises determining whether a transition was made from the first oplock state to a state of lesser caching. 
     
     
         39 . The system of  claim 35 , further comprising instructions for sending an acknowledgement that the first oplock state is broken. 
     
     
         40 . The system of  claim 35 , further comprising instructions for sending an indication of a level at which the first oplock state is broken.