What is an IXP
An Internet Exchange Point (IXP) is a network facility that enables the interconnection and exchange of Internet traffic between more than two independent Autonomous Systems.
An IXP provides interconnection only for Autonomous Systems.
An IXP does not require the Internet traffic passing between any pair of participating Autonomous Systems to pass through any third Autonomous System, nor does it alter or otherwise interfere with such traffic.
“Autonomous Systems” has the meaning given in BCP6/RFC1930 , “Guidelines for creation, selection, and registration of an Autonomous System (AS)”.
“Independent” means Autonomous Systems that are operated by organisational entities with separate legal personality.”
See a list of IXPs in different regions here:
The Benefits of Peering
Definitions: ASN (new)
"An AS is a group of IP networks operated by one or more network operator(s) that has a single and clearly defined external routing policy. Exterior routing protocols are used to exchange routing information between Autonomous Systems." (source: APNIC)