Modeling the Internet from the scratch: Link-layer, LAN, Switch - Code snippet: Build network-2

network.go

func Build() (host1 *link.Host, host2 *link.Host, host3 *link.Host,
    swch1 *link.Switch, swch2 *link.Switch) {
    // setup node
    ...
    // setup interface
    intf1 := link.NewInterface(40001, link.AddrFromStr("11-11-11-11-11-11"), host1)
    attachInterface(host1, intf1)
  
    intf2 := link.NewInterface(40002, link.AddrFromStr("22-22-22-22-22-22"), host2)
    attachInterface(host2, intf2)
  
    intf3 := link.NewInterface(40003, link.AddrFromStr("33-33-33-33-33-33"), host3)
    attachInterface(host3, intf3)
  
    sp11 := link.NewSwitchPort(40004, swch1)
    sp12 := link.NewSwitchPort(40005, swch1)
    sp13 := link.NewSwitchPort(40006, swch1)
    attachSwchInterface(swch1, sp11, "1")
    attachSwchInterface(swch1, sp12, "2")
    attachSwchInterface(swch1, sp13, "3")
  
    sp21 := link.NewSwitchPort(40007, swch2)
    sp22 := link.NewSwitchPort(40008, swch2)
    attachSwchInterface(swch2, sp21, "1")
    attachSwchInterface(swch2, sp22, "2")
}