'Configure Node according to (optional) parameters:
mac: MAC address for default interface
ip: IP address for default interface
ifconfig: arbitrary interface configuration
Subclasses should override this method and call
the parent class\'s config(**params)'

def config(self, mac=None, ip=None, defaultRoute=None, lo='up', **_params):

    r = {}
    self.setParam(r, 'setMAC', mac=mac)
    self.setParam(r, 'setIP', ip=ip)
    self.setParam(r, 'setDefaultRoute', defaultRoute=defaultRoute)
    self.cmd(('ifconfig    lo    ' + lo))
    return r
