Most transit networks have some sort of blanket notification that they can send to customers. Something like between 12AM and 6AM sometime next week you may or may not have a moderate or severe impact, but we're not going to give you details. It also depends on the peering that is being added or removed. The larger providers are mostly static. I can't imagine Level 3 permanently depeering from Verizon for example. Also, if paths change but latency and hop count are still acceptable most customers will not notice the change. The same goes for outages. Also, where do you draw the line. For example if someone severs a peering with a content network like google some of their downstreams will care others will not. If ISP's notified everyone of every change it would more or less become spam so I can see an argument for both. In large transit networks it probably comes down to the predicted impact of the a particular change versus visibility and contractual liabilities. 2011/12/28 Andy Susag <asusag@ifncom.net>
Hi All,
Just a quick question for those of you running ISPs with BGP downstreams.
If you add or remove an upstream provider to your network, do you provide notification to your downstream customers? Likely, it would cause a shift in their traffic. If they are peering with multiple ISPs themselves, they may see a traffic flux.
I know for a fact that our upstreams do not notify us of events so we tend to not send out these sort of notifications. Just wonder what everyone else does or if anyone happens to know "best practice"
Thanks,
Andy