// Copyright (c) 2008 DMTF.  All rights reserved.
   [Experimental, Version ( "2.19.0" ), 
    UMLPackagePath ( "CIM::Network::Topology" ), 
    Description ( 
       "TopologyGraph is a general structure for representing network "
       "topologies. Often, a topology graph consists of a set of nodes "
       "and a set of edges which connect the nodes. The TopologyGraph "
       "structure is slightly different, in order to support "
       "multipoint links and to express the connectivity within what "
       "would normally be considered a \'node\'. Multipoint links "
       "occur in entities such as IP subnets, where all of the IP "
       "endpoints on the subnet can communicate directly, and Ethernet "
       "links where all of the Ethernet interfaces on the shared media "
       "can communicate directly. An example of connectivity within a "
       "node is when the various endpoints/interfaces on a router are "
       "connected through the router\'s forwarding mechanism. There "
       "may be different groups of endpoints which communicate within "
       "their groups exclusively. This is modeled as a "
       "DeviceConnectivityCollection. \n"
       "\n"
       "To represent these examples in a graph structure, "
       "TopologyGraph generalizes the node and edge structures of a "
       "typical graph. It is a collection of ConnectivityCollections, "
       "which can communicate with one another, and are at the same "
       "protocol layer. ConnectivityCollections are aggregated into "
       "Topology Graphs using the MemberOfCollection relationship. \n"
       "\n"
       "The actual network topology encoded in TopologyGraph is "
       "extracted by connecting the ConnectivityCollection instances "
       "that share common ProtocolEndpoint instances. For example, if "
       "the graph contains three collections, defined as: \n"
       "- Router1={PE1, PE2}, a DeviceConnectivityCollection \n"
       "- Link1={PE2, PE3}, an IPConnectivitySubnet \n"
       "- Router2={PE3, PE4}, a DeviceConnectivityCollection \n"
       "then we can determine that the PE2 interface on Router1 is "
       "connected to the PE3 interface on Router2 via the subnet "
       "Link1. By finding all of the endpoints that are in multiple "
       "ConnectivityCollections within the graph, and connecting those "
       "Collections with common endpoints, we can construct the "
       "network topology." )]
class CIM_TopologyGraph : CIM_Collection {

      [Key, Override ( "InstanceID" ), 
       Description ( 
          "Within the scope of the instantiating Namespace, "
          "InstanceID opaquely and uniquely identifies an instance "
          "of this class. In order to ensure uniqueness within the "
          "NameSpace, the value of InstanceID SHOULD be constructed "
          "using the following \'preferred\' algorithm: \n"
          "<OrgID>:<LocalID> \n"
          "Where <OrgID> and <LocalID> are separated by a colon "
          "\':\', and where <OrgID> MUST include a copyrighted, "
          "trademarked or otherwise unique name that is owned by "
          "the business entity creating/defining the InstanceID, or "
          "is a registered ID that is assigned to the business "
          "entity by a recognized global authority (This is similar "
          "to the <Schema Name>_<Class Name> structure of Schema "
          "class names.) In addition, to ensure uniqueness <OrgID> "
          "MUST NOT contain a colon (\':\'). When using this "
          "algorithm, the first colon to appear in InstanceID MUST "
          "appear between <OrgID> and <LocalID>. \n"
          "<LocalID> is chosen by the business entity and SHOULD "
          "not be re-used to identify different underlying "
          "(real-world) elements. If the above \'preferred\' "
          "algorithm is not used, the defining entity MUST assure "
          "that the resultant InstanceID is not re-used across any "
          "InstanceIDs produced by this or other providers for this "
          "instance\'s NameSpace. \n"
          "For DMTF defined instances, the \'preferred\' algorithm "
          "MUST be used with the <OrgID> set to \'CIM\'." )]
   string InstanceID;


};