//
// Copyright (C) 2011 Juan Luis Garrote Molinero
// Copyright (C) 2013 Zsolt Prontvai
//
// This program is free software; you can redistribute it and/or
// modify it under the terms of the GNU Lesser General Public License
// as published by the Free Software Foundation; either version 2
// of the License, or (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with this program; if not, see <http://www.gnu.org/licenses/>.
//

package inet.linklayer.ieee8021d.rstp;
import inet.linklayer.contract.ISpanningTree;

//
// Implements the Rapid Spanning Tree Protocol (IEEE 802.D-2004) for IEC 48-bit
// MAC addresses. It is a complete implementation except it doesn't fall back
// to STP when peers don't support RSTP.
//
// RSTP is a network protocol that ensures a loop-free topology for any
// bridged Ethernet local area network. The basic function of RSTP
// is to prevent bridge loops and the broadcast radiation that results from them.
// Spanning tree also allows a network design to include spare (redundant) links to
// provide automatic backup paths if an active link fails, without the danger of
// bridge loops, or the need for manual enabling/disabling of these backup links.
// RSTP is an improved version of STP, providing faster convergence.
//
// RSTP makes use of per-port configuration data such as cost and priority.
// They can be set using ~L2NetworkConfigurator. Port state is kept in the switch's
// ~InterfaceTable.
//
// @see L2NetworkConfigurator, InterfaceTable
//
simple RSTP like ISpanningTree
{
    parameters:
        // The hello time is the time between each bridge protocol data unit (BPDU) that is sent on a port.
        // This time is equal to 2 seconds (sec) by default, but you can tune the time to be between 1 and 10 sec.
        double helloTime @unit("s") = default(2s);

        // The forward delay is the time that is spent in the listening and learning state. This time is equal to 6 sec by default,
        // but you can tune the time to be between 4 and 30 sec.
        double forwardDelay @unit("s") = default(6s);

        // The max age timer controls the maximum length of time that passes before a bridge port saves its configuration BPDU information.
        // This time is 20 sec by default, but you can tune the time to be between 6 and 40 sec.
        double maxAge @unit("s") = default(20s);

        // The migrate time is the time after which a non-assigned port becomes designated. This time is equal to 6 sec by default,
        // but you can tune the time to be between 4 and 30 sec.
        double migrateTime @unit ("s")= default(3s);

        // The topology change while time is the time while a port will send TC=true (Topology Change Notification)
        double tcWhileTime @unit("s") = default(6s);

        // The bridge priority determines which bridge is elected as the root bridge. If the switch has a bridge priority that is lower than all
        // the other switches, the other switches automatically select the switch as the root switch.
        int bridgePriority = default(32768);

        // The path to the InterfaceTable module
        string interfaceTablePath = default("^.interfaceTable");

        // The path to the MACAddressTable module
        string macTablePath = default("^.macTable");

        // Shows the spanning tree by coloring connections in the network graphics.
        // Label ethernet interface with port role and status. Mark root switch
        bool visualize = default(false);

        // If true, edge ports immediately become designated/forwarding, else it will have to wait to get designated.
        bool autoEdge = default(true);

        @display("i=block/network2");
    gates:
        input relayIn;
        output relayOut;
}
