I like would to know what are best practices for an internet exchange. I have some concerns about the following; Can the IXP members use RFC 1918 ip addresses for their peering?
No. Those IP addresses will at least appear on traceroutes; also, it might not be such a good idea to use the same RFC1918 space (accidentally) on different IXPs. This will get your skin crawling (thing IGP, or at least config databases)... IXPs can usually get a v4 and a v6 block for their peering grid easily.
Anyone with a decently configured firewall would block IP packets with source address from RFC1918 coming from the Internet. Your IXP would appear as a black hole in traceroute printout because the ICMP replies sent from the IXP IP addresses would be blocked. A while ago I've described a few more caveats in an article (see http://blog.ioshints.info/2008/08/private-ip-addresses-in-public-networks.ht ml). Ivan http://www.ioshints.info/about http://blog.ioshints.info/