Mastering Python Networking

Python with the BGP speaker library

The first BGP speaker code in Chapter11_5.py is very similar to the BGP speaker example on the Ryu readthedocs documentation, http://ryu.readthedocs.io/en/latest/library_bgp_speaker.html#example, with a few exceptions, as we will see. Since we are launching the application directly from Python, we need to import the Ryu event queue in the form of eventlet as well as the BGP speaker library:

import eventlet...from ryu.services.protocols.bgp.bgpspeaker import BGPSpeaker

We will define two callback functions for the BGP speaker for BGP neighbor detection and best-path change:

def dump_remote_best_path_change(event):    print 'the best path changed:', event.remote_as, event.prefix,        event.nexthop, event.is_withdraw ...