What is an Internet exchange point?
Why have local Internet exchanges?
Who operates the Pittsburgh Internet Exchange?
Who can become a member of PitX?
Who are the current members of PitX?
Do PitX members get to use the upstream Internet connectivity of other members?
What is the difference between peering and transit?
Can my organization pick and choose its peers at PitX?
Is there any downside to being a PitX member?
How can my organization connect to PitX?
What are the technical details of connecting to PitX?
How much will it cost my organization to become a member of PitX?
How does my organization apply for PitX membership?
What are some other Internet exchange points?
My question wasn't answered here.
What is an Internet exchange point?
An "exchange point" is an interconnection between at least two networks, where traffic destined for either system can be handed off.
Why have local Internet exchanges?
A direct interconnection between two networks is naturally the most efficient way for those networks to exchange data. If two networks in the same area need to exchange data but are not connected to a local exchange point, they will instead pass their data through their upstream Internet providers. This incurs added costs and delays, as upstream providers charge by capacity or utilization, and the traffic will often be passed through other cities before reaching its destination. In the case of Pittsburgh, most local traffic actually passes through Washington DC, New York City, or Chicago. Because of physical limitations as well as congestion on the public Internet, this represents a significant delay as well as an unnecessary expense.
Who operates the Pittsburgh Internet Exchange?
The Pittsburgh Internet Exchange, or PitX, is operated by pair Networks, Inc, a world class Web hosting provider that is headquartered in Pittsburgh. The physical implementation of PitX resides in pair's Class A datacenter in the Southside. As an experienced, accomplished, access-neutral Internet services company in Pittsburgh, pair is uniquely qualified to operate such a service. Moreover, with over 90,000 Web sites hosted (as of April 2000), there is significant local traffic from Web surfers accessing pair's network.
Who can become a member of PitX?
Any organization that already has dedicated Internet connectivity and is both interested and capable of managing a connection is entirely welcome. Please note that PitX does not provide you with "access to the Internet". It only allows you to reach the other PitX members, and they have agreed to exchange traffic only with organizations that already have other Internet transit (definitions appear elsewhere in this document). If your organization has a dedicated connection to a local provider, your best approach would be to encourage that provider to become a PitX member, if they have not done so already. If your dedicated connectivity is from a national provider or a provider unwilling to join PitX, then you should consider becoming a member.
Who are the current members of PitX?
The current membership list is available on this site.
Do PitX members get to use the upstream Internet connectivity of other members?
Absolutely not. Using one network to reach other networks on the Internet is known as "transit", and transit is not allowed on PitX. You may send traffic only to PitX members' networks, no further. This restriction avoids commercial entanglements and helps pace the growth of the exchange point.
What is the difference between peering and transit?
Peering allows two networks to exchange traffic only when that traffic is destined specifically for the receiving network. Transit uses one network to reach other networks. Peering is often a free service between local or similarly sized networks, as it is equally beneficial to both parties. Transit is invariably a paid service, since it is the essential portion of "Internet access". PitX is intended for peering only; transit should be sold over dedicated point-to-point circuits elsewhere. PitX will not function as a point of presence for access providers seeking to sell Internet access.
Can my organization pick and choose its peers at PitX?
At present, all PitX members are required to sign and adhere to the Participating Network Contract, which includes a Multi-Lateral Peering Agreement, or "MLPA". The MLPA ensures that all members peer on an equal basis. Because fully-meshed peering becomes very difficult to manage as the number of peers increases, we are operating two redundant route servers for PitX. The route servers replicate all peered routes to all peers.
Is there any downside to being a PitX member?
We don't believe so. Although the benefits of peering with any other network are generally bilateral, those benefits are very well-balanced. For a specific example, consider two dialup ISPs, normally in staunch competition, peering at PitX. The only traffic exchanged between those networks would be at the request of a dialup user on either end, either to visit a Web site at the other provider, to send e-mail, or to communicate dynamically with a dialup user at the other provider, such as via ICQ or to play games. The benefits accrue to both providers, and it is ultimately the providers who do not peer at PitX that may suffer competitively. A user whose traffic is going through New York City to chat with a friend across town is not going to be as satisfied with that performance as they could be, and they will blame their ISP.As an aside, any sniffing or traffic profiling of traffic other than that passing through a PitX member's own switch port is forbidden. This is prevented to the extent possible through configuration, and attempted violations are actively tracked. Any abusive behavior will result in a full investigation.
How can my organization connect to PitX?
First, ensure that you meet the requirements, especially that you have dedicated Internet connectivity, preferably at T-1 speeds or higher, to at least one provider (ISP or backbone). Second, go through the membership requirements and application procedures. Third, provision a circuit to reach PitX, purchase, configure, and install the equipment, set up your peering, and you're done.
What are the technical details of connecting to PitX?
Specific technical documentation is available on this site.
How much will it cost my organization to become a member of PitX?
Because of enthusiastic participation from founding members, we have been able to meet our cost-recovery needs through overall savings benefits. Therefore, we have waived all participation fees for the foreseeable future. If this changes at any time, we will publish the details here. Please note that members are still responsible for their own costs to connect to the exchange, and unusual connections may incur additional costs which will be passed along to the member.
How does my organization apply for PitX membership?
Membership requirements and application procedures are available on this site.
What are some other Internet exchange points?
The best-known are the public peering points - MAE-East, MAE-West, Sprint NAP, AADS, PacBell NAP, PAIX, and a few others. Unfortunately, some of these exchange points are severely overburdened, and performance problems are not at all uncommon. Local exchange points exist in many areas of the world, although not all are actively maintained. A detailed list can be found here.
My question wasn't answered here.
Feel free to ask us any other question at