INTERNET EXCHANGE POINT
An Internet exchange point (IX or IXP) is a physical transportation that allows dissimilar Internet service providers (ISPs) to exchange Internet traffic between their networks (autonomous systems) by way of mutual peering agreements, which allow traffic to be exchanged with no cost. IXPs reduce the piece of an ISP's traffic which must be delivered via their upstream transit providers, thus reducing the Average Per-Bit Delivery Cost of their service. in addition, the enlarged number of paths learned during the IXP get better routing competence and fault-tolerance.
The main reason of an IXP is to permit networks to interconnect straight, via the exchange, rather than through one or more 3rd party networks. The compensation of the direct interconnection is frequent, but the prime reasons are latency, cost, and bandwidth. Traffic passing during an exchange is usually not billed by any party, while traffic to an ISP's upstream supplier is. The straight interconnection, frequently situated in the same city as both networks, avoids the need for data to travel to other cities (potentially on other continents) to get from one network to a different, thus dropping latency. The third benefit, speed, is most obvious in areas that have poorly residential long-distance connections. ISPs in these regions might have to pay between 10 or 100 times more for data transport than ISPs in North America, Europe or Japan. consequently, these ISPs naturally have slower, more limited associations to the rest of the internet. though, a connection to a local IXP may let them to transfer data with no limit, and with no cost, vastly improving the bandwidth between customers of the two adjacent ISPs.
A usual IXP consists of one or more network switches, to which every of the participating ISPs connect. Previous to the subsistence of switches, IXPs usually utilized FOIRL hubs or FDDI rings, migrating to Ethernet and FDDI switches as those became accessible in 1993 and 1994. ATM switches were in brief used at a few IXPs in the late 1990s, accounting for just about 4% of the market at their peak, and there was an abortive effort by the Stockholm IXP, NetNod, to make use of SRP/DPT (an ill-fated conjoinment of FDDI and SONET), but Ethernet has prevailed, accounting for more than 95% of all accessible Internet exchange switch fabrics. All Ethernet port speeds are to be found at modern IXPs, ranging from 10 Mbit/s ports in use in small developing-country IXes, to ganged 10 Gbit/s ports in major centers like Seoul, New York, London, Frankfurt, Amsterdam, and Palo Alto.
When an IXP incurs any operating costs, those costs are usually shared among all of its participants. At the more expensive exchanges, participants pay a monthly or annual fee, typically firm by the speed of the port or ports which they're using, or much less Usually by the volume of traffic which they're passing transversely the exchange (fees based on quantity of traffic are disliked because they offer a counterincentive to development of the exchange). Some communications also have a setup fee, to offset the costs of the switch port and any media adaptors (GBICs, SFPs, XFPs, XENPAKs, et cetera) which the new contributor requires, and the labor of configuring it to serve them.