什么意思Each node i periodically broadcasts the weights of all edges (i,j) incident on it (this is the link state) to all its neighbors. Each link state packet (LSP) has a sequence number seq. The mechanism for dissemination is flooding. This helps each node eventually compute the topology of the network, and independently determine the shortest path to any destination node using some standard graph algorithm like Dijkstra’s.

这段描述是指链路状态路由协议(Link State Routing Protocol)，其工作方式是每个节点周期性地向所有邻居节点广播其相邻链路的状态信息，包括链路权重和序列号。这些状态信息被称为链路状态分组(LSP)。这种广播机制被称为泛洪(flooding)。通过收集邻居节点广播的LSP，每个节点可以计算出网络的拓扑结构，并使用一些标准图算法（如Dijkstra算法）独立地确定到任何目标节点的最短路径。

相关问题

The Deadline policy \D" indicates the minimum rate at which a Data Writer will send data. It also indicates how long a Data Reader is willing to wait for new data. This policy is useful for cases where a Topic is expected to have each instance updated periodically. The default is a value of in¯nity, it means there is no deadline. For example, the braking electronic unit requires a new value of \the vehicle speed" to be received every 100 ms. If that deadline passes without a new command, the application will be noti¯ed and can apply a default safe command until a new appropriate command comes in. Bene¯ts34:

截止时间策略"D"表示Data Writer发送数据的最小速率。它还表示Data Reader愿意等待新数据的时间长度。该策略对于预期每个实例定期更新的主题非常有用。默认值为无限大，表示没有截止时间。例如，制动电子单元要求每100毫秒接收到"车辆速度"的新值。如果超过该截止时间而没有新的命令，则应用程序将收到通知，并可以应用默认的安全命令，直到接收到新的适当命令为止。好处包括：

The constructor of the ViewSimple class registers the view with the model (the library) using the addListener method of the model, creates a JLabel object, stores it in the label instance variable of the ViewSimple class, initializes it to display the total number of books borrowed by all users of the library, and adds the label to the view (which is a frame). The update method of the ViewSimple class updates the text of the label as necessary so that the label always displays the current value of the total number of books borrowed by all users of the library. Since the ViewSimple does not have any button, it cannot perform any action, therefore the corresponding controller ControllerSimple does nothing. (We still want to have the ControllerSimple class so that our application follows the correct Model-View-Controller design pattern.) Fifth, create a GUI class with a main method. In this main method, create an anonymous class that implements the Runnable interface with a run method and use the javax.swing.SwingUtilities.invokeLater method to run that code on the event dispatch thread.

This GUI class should create an instance of the ModelSimple, an instance of the ViewSimple, and an instance of the ControllerSimple. Then, it should register the view with the model by calling the addListener method of the model and passing in the view as a parameter. Finally, it should set the size of the view and make it visible. Here's an example code:

public class LibraryGUI {
    public static void main(String[] args) {
        ModelSimple model = new ModelSimple();
        ViewSimple view = new ViewSimple();
        ControllerSimple controller = new ControllerSimple(model, view);

        model.addListener(view);
        
        JFrame frame = new JFrame("Library");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.add(view);
        frame.pack();
        frame.setVisible(true);

        // run the code on the event dispatch thread
        SwingUtilities.invokeLater(new Runnable() {
            public void run() {
                // update the view periodically
                while (true) {
                    try {
                        Thread.sleep(1000); // wait for 1 second
                    } catch (InterruptedException e) {}
                    model.update(); // update the model
                }
            }
        });
    }
}

This code creates an infinite loop that periodically updates the model and the view. You can modify the frequency of the updates by changing the value of the sleep time. Note that this is just a simple example to demonstrate the basic structure of a Model-View-Controller application. In practice, you would typically use event listeners to trigger updates instead of polling the model periodically.