The Routing Policy Specification Language (RPSL) is a language commonly used by ISP

Internet service provider

An Internet service provider is a company that provides access to the Internet. Access ISPs directly connect customers to the Internet using copper wires, wireless or fiber-optic connections. Hosting ISPs lease server space for smaller businesses and host other people servers...

s to describe their routing policies.

The routing policies are stored at various whois

WHOIS

WHOIS is a query and response protocol that is widely used for querying databases that store the registered users or assignees of an Internet resource, such as a domain name, an IP address block, or an autonomous system, but is also used for a wider range of other information. The protocol stores...

 databases including RIPE

RIPE

Réseaux IP Européens is a forum open to all parties with an interest in the technical development of the Internet. The RIPE community’s objective is to ensure that the administrative and technical coordination necessary to maintain and develop the Internet continues...

, RADB and APNIC. ISPs (using automated tools) then generate router configuration files that match their business and technical policies.

RFC 2622 describes RPSL, and replaced RIPE-181.

RFC 2650 provides a reference tutorial to using RPSL in the real-world.

RPSL has been extended with RPSL-NG (RPSL-Next Generation) effort to support IPv6

IPv6

Internet Protocol version 6 is a version of the Internet Protocol . It is designed to succeed the Internet Protocol version 4...

 routing policies and multicast

Multicast

In computer networking, multicast is the delivery of a message or information to a group of destination computers simultaneously in a single transmission from the source creating copies automatically in other network elements, such as routers, only when the topology of the network requires...

routing policies. RPSL-NG is defined in RFC 4012.

RPSL Tools and Programs

• RtConfig - automatically generate router configuration files from RPSL registry entries (This software is part of the IRRToolSet)