Network-to-network interface definition
Network-to-network interface (NNI) refers to the point of interconnection between two or more separate networks, allowing them to communicate with each other. This is particularly important for service providers that want to exchange traffic or extend services across each other’s infrastructures, such as between two ISPs. These NNIs often come with certain agreed-upon standards and protocols, designed for efficient traffic exchange.
See also: application programming interface
Network-to-network interface use cases:
- Data centers. Companies with multiple data centers in different locations may use NNIs to connect these facilities.
- Telecommunication carriers. Mobile network operators may use NNIs to connect their networks with other operators, especially for international roaming agreements where a subscriber of one carrier uses another carrier’s network in another country.
- Content delivery networks (CDNs). CDNs often optimize the delivery of web content and media by connecting ISPs and data centers to efficiently cache and deliver content close to the user.
- Internet exchanges. Internet exchanges are physical locations where ISPs and other network providers come together to exchange traffic. Each of them has an NNI with the exchange to help exchange traffic efficiently.
Types of network-to-network interface:
- Physical NNI. Refers to the physical connection (e.g., optical fiber links) between the two networks.
- Logical NNI. Involves setting up logical connections or virtual circuits over the physical interconnections.
- Routing NNI. Involves setting up routing protocols to exchange routing information and manage the paths taken by data traffic between the networks.