{"id":5496,"date":"2024-06-20T12:14:30","date_gmt":"2024-06-20T10:14:30","guid":{"rendered":"https:\/\/oopm.org\/?page_id=5496"},"modified":"2024-10-13T22:13:22","modified_gmt":"2024-10-13T20:13:22","slug":"11-3-2-graph-representing-a-computer-network","status":"publish","type":"page","link":"https:\/\/oopm.org\/?page_id=5496","title":{"rendered":"11.3.2 Graph representing a computer network"},"content":{"rendered":"
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Here we sketch a very simple example representing the structure of a computer network using class Graph<\/code>. A Node<\/code> in the graph represent a computer (server) and an Edge<\/code> represents a cable.<\/p>\n\n\n\n

   class<\/strong> Network: Graph\n      class<\/strong> Node::< \n         send(receiver: ref<\/strong> Node,P: ref<\/strong> Packet):\n            :::\n         receive(send: ref<\/strong> Node,P: ref<\/strong> Packet): \n            ...\n         :::\n         ...\n      class<\/strong> Edge::<\n         bandWidth: var<\/strong> integer\n         send(receiver: ref<\/strong> Node,P: ref<\/strong> Packet):\n            ...\n         ...\n      class Packet(S: var String):\n          ...<\/code><\/pre>\n\n\n\n
    \n
  • Class Network<\/code> is a subclass of Graph<\/code>.<\/li>\n\n\n\n
  • It has further bindings of Node<\/code> and Edge<\/code> from Graph<\/code>.<\/li>\n\n\n\n
  • It adds a class Packet<\/code> representing the packets being communicated in the network.<\/li>\n<\/ul>\n\n\n\n
    Class Node<\/code> is extended with:<\/p>\n\n\n\n
      \n
    • A method send<\/code> that send the Packet<\/code> P<\/code> to the node represents by receiver<\/code>.<\/li>\n\n\n\n
    • A method receive<\/code> that receives a a Packet<\/code> P<\/code> from the Node<\/code> represented by receiver. <\/li>\n<\/ul>\n\n\n\n
      Class Edge<\/code> is extended with:<\/p>\n\n\n\n
        \n
      • An integer<\/code> bandWidth<\/code> representing the bandwidth of the cable represented by the Edge<\/code>.<\/li>\n<\/ul>\n\n\n\n
        Th details of send in Node<\/code> may be sketched as follows:<\/p>\n\n\n\n
        send(receiver: ref<\/strong> Node,P: ref<\/strong> Packet):\n   map(receiver).send(receiver,P)<\/code><\/pre>\n\n\n\n
        Send<\/code> uses an ancillary method map<\/code> to find the edge<\/code> representing the cable that has the fastest connection to the receiver<\/code>, and the invokes send<\/code> on this Edge<\/code>.<\/p>\n\n\n\n
        We do not add further details of this examples. It is major task to implement a computer network. It also involves using parallel programming for listening on input\/output ports for packages being transmitted \/ received. Parallel programming is described in chapter