### On Mon, 11 Mar 2002 04:49:46 -0500 (EST), Sean Donelan ### <sean@donelan.com> casually decided to expound upon Vadim Antonov ### <avg@exigengroup.com> the following thoughts about "Re: Telco's write ### best practices for packet switching networks": SD> My simple question is why do exchange point prefixes or backbone SD> network prefixes need to be announced to peers or customers? SD> SD> This has been something which has bugged me ever since I connected SD> a router to mae-east. I think the main justification one could use (and I don't necessarily agree with this) is to aide in troubleshooting. Announcing the space may make it easier for multiple parties to troubleshoot through their backbone. On the flipside of this argument of course is why not filter that space to only your NOCs and engineers? Now the counter-argument to that might be that the space starts to add up in terms of bloating ACLs and such. One could go back and forth on this all day I suppose including arguments for and against troubleshooting from production devices vs troubleshooting from a backend system. Another reason mae-east was announced at least historically may have been to help support activities such as the Routing Arbiter Project. I know from experience that due to the nature of how they were positioned within exchange points, the routeservers needed to be reachable by Merit personnel. However, the proper solution there should have been for only Merit's primary transit provider to carry those routes and possibly filter as much as possible the space except to Merit. There were workable solutions even back then. I think we all just chose the path of least resistance because it was easier and the risk factours were perceived to be low. We all know that was a false assumption. I remember the first smurf attack against mae-east and how it knocked out quite a few peers. -- /*===================[ Jake Khuon <khuon@NEEBU.Net> ]======================+ | Packet Plumber, Network Engineers /| / [~ [~ |) | | --------------- | | for Effective Bandwidth Utilisation / |/ [_ [_ |) |_| N E T W O R K S | +=========================================================================*/