- What is an Internet Exchange (IXP)?
- What is "transit"?
- What is an Autonomous System?
- When should an Autonomous System be created?
- What is an Autonomous System Number?
- When is a Public Autonomous System number required?
- Does an ISP need a public AS Number to peer with the IXP?
- Where can I get my Public AS Number? Who provides the AS Number?
- What is the basic requirement for getting an AS number?
- When can I use a Private Autonomous System number?
- What is NIXI?
- Who can join NIXI?
What is an Internet Exchange (IXP)?
Internet Exchange Points (IXPs) are the most critical part of the Internet's Infrastructure. An Internet Exchange Point is a facility that allows Internet Service Providers to "meet" and exchange traffic, also called peering. This saves money on International bandwidth for the ISPs and improves connectivity for their customers by reducing latency.
What is "transit"?
When one ISP pays another ISP for the right to send traffic across their network, this is known as "transit".
What is an Autonomous System?
An Autonomous System (AS) is a group of IP networks operated by one or more network operator/s which has a single and clearly defined external routing policy. Exterior routing protocols are used to exchange routing information between Autonomous Systems.
When should an Autonomous System be created?
An AS needs to be created if a network connects to more than one AS with different routing policies. Some common examples of Autonomous Systems are networks connected to two or more upstream service providers or exchange points, and networks peering locally at exchange points.
What is an Autonomous System Number?
A public AS has a globally unique number, an Autonomous System number (ASN), associated with it; this number is used in both the exchange of exterior routing information (between neighboring Autonomous Systems), and as an identifier of the AS itself. Autonomous system numbers are used by BGP to describe administrative boundaries on the Internet.
There are two types of Autonomous System numbers; Public AS numbers and Private AS numbers.
When is a Public Autonomous System number required?
A Public AS number is required only when an AS is exchanging routing information with other Autonomous Systems on the public Internet. That is, all routes originating from an AS is visible on the Internet.
Does an ISP need a public AS Number to peer with the IXP?
It is strongly recommended that all ISPs get a public AS number. While there are ways to have an ISP connect and gain the benefits of L2 IXP without a public AS number, an ISP with their own AS number has advantages over ISPs who do not. The core requirement for an ISP to qualify for a Globally Unique AS number is that they be multihomed. For joining NIXI, having an ISP License and an AS number are necessary conditions.
Where can I get my Public AS Number? Who provides the AS Number?
RIRs (Regional Internet Registries) provide the public AS numbers. There are currently five active RIRs providing AS Numbers. These are ARIN (www.arin.net (External website that opens in a new window)), APNIC (www.apnic.net (External website that opens in a new window)), RIPE_NCC (www.ripe.net (External website that opens in a new window)), LACNIC (www.lacnic.net (External website that opens in a new window)) and AFRINIC (www.afrinic.net (External website that opens in a new window)).
Organizations in Asia Pacific region need to apply to APNIC for their requirements of AS numbers.
What is the basic requirement for getting an AS number?
The basic requirement for an organisation to qualify for a Globally Unique AS number is that they be multihomed.
When can I use a Private Autonomous System number?
A Private AS number should be used if an AS requires to do BGP with a single provider. As the routing policy between the AS and the provider will not be visible in the Internet, a Private AS Number can be used for this purpose.
IANA has reserved AS64512 through to AS65535 to be used as private ASes.
What is NIXI?
NIXI stands for the National Internet Exchange of India. NIXI is a not for profit Organization under section 25 of the Companies Act 1956, and was registered on 19th July, 2003. NIXI was set up for peering of ISPs among themselves for the purpose of routing the domestic traffic within the country, instead of taking it all the way to US/Abroad, thereby resulting in better quality of service (reduced latency) and reduced bandwidth charges for ISPs by saving on International Bandwidth.
Who can join NIXI?
Any ISP can join NIXI. Please see Join Us page for more details.