Resource specification rspec each nm supported

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resource specification ( RSpec ). Each NM-supported object—VMs and resource pools—can be referenced with a resource capability ( rcap ). An rcap is a 128-bit random string, where knowledge of an rcap corresponding to a particular object ( RSpec ) lets the bearer perform any operation supported by the object. The node manager is responsible for maintain- ing a persistent table of rcap / RSpec bindings. In way of overview, the NM interface consists of five operations for creating and manipulating resource pools and virtual machines: rcap = CreatePool(rspec, slice name) rcap[ ] = GetRcap( ) rspec = GetRspec(rcap) rcap = SplitPool(rcap, rspec) Bind(rcap, slice name) A root resource pool is created on behalf of some slice name using the Cre- atePool operation. This operation can only be invoked by the privileged owner- VM ( site admin ) on the node, and is generally used when the node is initialized. 12
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Typically, the owner creates a resource pool for each trusted infrastructure service, and creates additional resource pools on behalf of any particular service that the owner wants to run on the node. At some future time, the slice named in the CreatePool operation retrieves the set of rcap s for pools allocated to it by calling the GetRcap operation. Once a slice has retrieved the rcap for a pool of resources, it can learn the RSpec associated with the pool by calling the GetRspec operation. A slice that possesses an rcap for a pool can create a new ‘sub-pool’ by calling SplitPool . This operation takes an rspec for the new sub-pool as an argument, and returns an rcap for the new pool. The RSpec for the original pool is reduced accordingly (i.e., calling GetRspec on the original rcap returns an RSpec corre- sponding to the remainder of resources after the split). A pool of resources is bound to a VM using the bind operation. If the VM does not already exist, this operation also creates the VM. If the VM does exist, the resources represented by the rcap are added to those currently bound to it. 4.4 Slice A slice is a set of VMs, with each element of the set running on a unique node. The individual VMs that make up a slice contain no information about the other VMs in the set, except as managed by the service running in the slice. As described in Section 4.2, each VM is initialized with a set of keys that allow the users that created to slice to remotely log into it, and with a user-provided bootscript that runs when the VM starts. Otherwise, all slice-wide state is maintained by the slice authority that created the slice on the users’ behalf, as described in Section 4.7. Slices are uniquely identified by name. Slice names are hierarchical, with each level of the hierarchy denoting the slice authority that is responsible for the behav- ior of all slices lower in the hierarchy. For example, plc.princeton.codeen names a slice created by the PLC slice authority, which has delegated to Princeton the right to approve slices for individual projects (services), such as CoDeeN. PLC defines
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  • Spring '10
  • CS
  • IP address, slice, Slice Authority

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