IXs are a little bit strange, as they are at their core practically identical to a simple ethernet switch you may find in your home or office (except your home switch is unlikely to be doing terabits per second of traffic). As IXs depend on the ethernet switches interest in only being the MAC addresses of traffic and not the Layer 3 IP addresses. However home and small and medium business (SMB) routers often come with defaults that make life a lot easier for networks way of desktop computers and common office equipment on them, these same defaults are at the very least annoying and at the very worst actively exploitable if put on a IX LAN with many untrusted participants.
