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at:tutorial:distribution [2009/01/28 17:31] – adding elisagat:tutorial:distribution [2009/01/28 17:34] elisag
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 As explained in the previous section, remote far references have been designed to be resilient to intermittent disconnections by default. This behaviour is desirable because it can be expected that many partial failures in mobile ad hoc networks are the result of transient network partitions. However, not all network partitions are transient. For example, a remote device has crashed or has moved out of the wireless communication range and does not return. Such permanent failures should also be dealt by means of compensating actions, e.g. application-level failure handling code. As explained in the previous section, remote far references have been designed to be resilient to intermittent disconnections by default. This behaviour is desirable because it can be expected that many partial failures in mobile ad hoc networks are the result of transient network partitions. However, not all network partitions are transient. For example, a remote device has crashed or has moved out of the wireless communication range and does not return. Such permanent failures should also be dealt by means of compensating actions, e.g. application-level failure handling code.
  
-To deal with permanent failures, AmbientTalk uses the concept of leasing. A lease denotes the right to access a resource for a specific duration that is negotiated by the owner of a resource and a resource claimant (called the lease grantor and lease holder, respectively) when the access is first requested.  At the discretion of the lease grantor a lease can be renewed, prolonging access to the resource. In AmbientTalk, we represent leases as a special kind of remote far references, which we call leased object references. +To deal with permanent failures, AmbientTalk uses the concept of leasing. A lease denotes the right to access a resource for a specific duration that is negotiated by the owner of a resource and a resource claimant (called the lease grantor and lease holder, respectively) when the access is first requested.  At the discretion of the lease grantor a lease can be renewed, prolonging access to the resource. In AmbientTalk, we represent leases as a special kind of remote far references, which we call //leased object references//
  
 ====Leased Object References==== ====Leased Object References====
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 <note> <note>
-leasedref module exports support primitives to manipulate time intervals (i.e. minutes, seconds, millisecs) so that you do not need to explicitly import the timer module. Remember to exclude those methods from the leasedref import statement if some other module has already imported them, e.g. if futures were imported.+leasedref module exports support primitives to manipulate time intervals (i.e. minutes, seconds, millisecs) so that you do not need to explicitly import the timer module. Remember to exclude those methods from the leasedref import statement if some other module has already imported them, e.g. if futures are enabled.
 </note> </note>
  
at/tutorial/distribution.txt · Last modified: 2009/01/30 16:13 by tvcutsem