Table Of Contents
Table Of Contents

Step 6. BGP Scenario and using loopbacks

Goals

[explanation]

Configuration

This step uses the following network:

../../../_images/step6789.png
network BGP_Topology_4
{
    @display("bgb=1328.6062,594.495");

    submodules:
        configurator: Ipv4NetworkConfigurator {
            @display("p=93,44");
        }
        visualizer: IntegratedMultiCanvasVisualizer {
            @display("p=243.2025,43.536247");
        }
        RB2: Router {
            @display("p=660.55,132.11");
        }
        RB3: Router {
            @display("p=660.55,223.68625");
        }
        RB4: Router {
            @display("p=765.6375,181.65125");
        }
        RC1: Router {
            @display("p=974.3112,385.82123");
        }
        RC2: Router {
            @display("p=1065.8875,336.28");
        }
        RC3: Router {
            @display("p=1065.8875,435.3625");
        }

        RB1: Router {
            @display("p=556.96375,181.65125");
        }
        RA4: Router {
            @display("p=349.79123,400.83374");
        }
        RA2: Router {
            @display("p=244.70375,342.285");
        }
        RA3: Router {
            @display("p=244.70375,442.86874");
        }

        RA1: Router {
            @display("p=153.1275,393.32748");
        }
        RC4: Router {
            @display("p=1151.4587,385.82123");
        }
        switch1: EtherSwitch {
            @display("p=54.045,391.82623");
        }
        switch2: EtherSwitch {
            @display("p=244.70375,250.70874");
        }
        switch3: EtherSwitch {
            @display("p=244.70375,534.445");
        }
        switch4: EtherSwitch {
            @display("p=660.55,33.0275");
        }
        switch5: EtherSwitch {
            @display("p=660.55,315.26248");
        }
        switch6: EtherSwitch {
            @display("p=1065.8875,237.1975");
        }
        switch7: EtherSwitch {
            @display("p=1065.8875,519.4325");
        }
        switch8: EtherSwitch {
            @display("p=1261.0499,382.81876");
        }
        host0: StandardHost {
            @display("p=53.28,251.415");
        }
        host1: StandardHost {
            @display("p=1260.405,251.415");
        }
    connections:
        RB2.ethg++ <--> Eth100M <--> RB4.ethg++;
        RB3.ethg++ <--> Eth100M <--> RB4.ethg++;
        RC1.ethg++ <--> Eth100M <--> RC2.ethg++;
        RC1.ethg++ <--> Eth100M <--> RC3.ethg++;
        RB4.ethg++ <--> Eth100M <--> RC1.ethg++;
        RB1.ethg++ <--> Eth100M <--> RB2.ethg++;
        RB1.ethg++ <--> Eth100M <--> RB3.ethg++;
        RB1.ethg++ <--> Eth100M <--> RA4.ethg++;
        RA4.ethg++ <--> Eth100M <--> RA2.ethg++;
        RA3.ethg++ <--> Eth100M <--> RA4.ethg++;
        RA2.ethg++ <--> Eth100M <--> RA1.ethg++;
        RA1.ethg++ <--> Eth100M <--> RA3.ethg++;
        RC4.ethg++ <--> Eth100M <--> RC2.ethg++;
        RC3.ethg++ <--> Eth100M <--> RC4.ethg++;
        switch1.ethg++ <--> Eth100M <--> RA1.ethg++;
        RA2.ethg++ <--> Eth100M <--> switch2.ethg++;
        RA3.ethg++ <--> Eth100M <--> switch3.ethg++;
        RB2.ethg++ <--> Eth100M <--> switch4.ethg++;
        RB3.ethg++ <--> Eth100M <--> switch5.ethg++;
        RC2.ethg++ <--> Eth100M <--> switch6.ethg++;
        RC3.ethg++ <--> Eth100M <--> switch7.ethg++;
        RC4.ethg++ <--> Eth100M <--> switch8.ethg++;
        switch1.ethg++ <--> Eth100M <--> host0.ethg++;
        switch8.ethg++ <--> Eth100M <--> host1.ethg++;
}

The configuration in omnetpp.ini is the following:

[Config Step6]
description = "BGP Scenario and using loopbacks"
network = BGP_Topology_4

# adding default routes in RA4 and RC1 and ask OSPF to distribute it within the AS
*.configurator.config = xml("<config> \
                                <interface hosts='RA4' names='eth0' address='192.168.x.x' netmask='255.x.x.x'/> \
                                <interface hosts='RB1' names='eth2' address='192.168.x.x' netmask='255.x.x.x'/> \
                                <interface hosts='RB4' names='eth2' address='192.168.x.x' netmask='255.x.x.x'/> \
                                <interface hosts='RC1' names='eth2' address='192.168.x.x' netmask='255.x.x.x'/> \
                                \
                                <interface among='host0 RA*' address='10.x.x.x' netmask='255.x.x.x'/> \
                                <interface hosts='RA*' address='10.x.x.x' netmask='255.x.x.x'/> \
                                \
                                <interface hosts='RB*' address='20.x.x.x' netmask='255.x.x.x'/> \
                                \
                                <interface among='host1 RC*' address='30.x.x.x' netmask='255.x.x.x'/> \
                                <interface hosts='RC*' address='30.x.x.x' netmask='255.x.x.x'/> \
                                \
                                <route hosts='host*' destination='*' netmask='0.0.0.0' interface='eth0' /> \
                                \
                                <route hosts='RA4' destination='*' netmask='0.0.0.0' interface='eth0' /> \
                                <route hosts='RC1' destination='*' netmask='0.0.0.0' interface='eth2' /> \
                             </config>")

# OSPF configuration
*.R*.hasOspf = true
*.R*.ospf.ospfConfig = xmldoc("OSPFConfig.xml")

*.RA4.ipv4.routingTable.routerId = "10.0.0.5"
*.RC1.ipv4.routingTable.routerId = "30.0.0.5"
*.RB1.ipv4.routingTable.routerId = "20.0.0.18"
*.RB4.ipv4.routingTable.routerId = "20.0.0.14"

# BGP configuration
*.RA4.hasBgp = true
*.RB1.hasBgp = true
*.RB4.hasBgp = true
*.RC1.hasBgp = true
*.R*.bgp.bgpConfig = xmldoc("BGPConfig_Redist.xml")
*.R*.bgp.redistributeOspf = "O IA"

# BGP routes are distributed internally within the AS
#*.RB1.bgp.redistributeInternal = true
#*.RB4.bgp.redistributeInternal = true

# enable BGP on RB2 and RB3
*.RB2.hasBgp = true
*.RB3.hasBgp = true

The BGP configuration:

<?xml version="1.0" encoding="ISO-8859-1"?>
<BGPConfig xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="BGP.xsd">

    <TimerParams>
        <connectRetryTime> 120 </connectRetryTime>
        <holdTime>         180 </holdTime>
        <keepAliveTime>    60  </keepAliveTime>
        <startDelay>       50  </startDelay>   <!--long enough for the intra-AS routing protocol to converge-->
    </TimerParams>

    <AS id="64500">
    	<!--router RA4-->
        <Router interAddr="10.0.0.1"/>
    </AS>
    
    <AS id="64600">
    	<!--router RB1-->
        <Router interAddr="20.0.0.6">
            <Neighbor address='20.0.0.5' nextHopSelf='true' />
            <Neighbor address='20.0.0.2' nextHopSelf='true' />
            <Neighbor address='20.0.0.17' nextHopSelf='true' />
        </Router>
                        
        <!--router RB4-->
        <Router interAddr="20.0.0.2">
            <Neighbor address='20.0.0.6' nextHopSelf='true' />
            <Neighbor address='20.0.0.5' nextHopSelf='true' />
            <Neighbor address='20.0.0.17' nextHopSelf='true' />
        </Router>        
        
        <!--router RB2-->
        <Router interAddr="20.0.0.5"/>
        
        <!--router RB3-->
        <Router interAddr="20.0.0.17"/>
    </AS>

    <AS id="64700">
    	<!--router RC1-->
        <Router interAddr="30.0.0.1"/>
    </AS>

    <!--bi-directional E-BGP session between RA4 and RB1-->
    <Session id="1">
        <Router exterAddr="192.168.0.5"/>
        <Router exterAddr="192.168.0.6"/>
    </Session>
    
    <!--bi-directional E-BGP session between RB4 and RC1-->
    <Session id="2">
        <Router exterAddr="192.168.0.1"/>
        <Router exterAddr="192.168.0.2"/>
    </Session>

</BGPConfig>

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