From ESNOG (although I am subscribed, I dont really receive notifications…) I saw this presentation, and then I found the main video reference.

BUM: 1.5Mbps -> that goes to all customer ports!! Small devices can’t cope with that.

Ratelimiting for BUM ingress/egress

Originally IXP is VPLS. Issue with long lasting flows / long lasting MACs

Solution: EVPN + ProxyARP/ND Agent.

I know EVPN is mainly for Datacenters but it is interesting the move to IXP. Although I remember reading about EVPN into Cisco IOS-XR platform that is mainly a ISP device.