pyasn is a Python extension module that enables very fast IP address to Autonomous System Number lookups.
Current state and Historical lookups can be done, based on the BGP / MRT file used as input.
pyasn is different from other ASN lookup tools in that it providers offline and historical lookups.
It provides utility scripts for users to build their own lookup databases based on any BGP/MRT dump file.
This makes pyasn much faster than online dig/whois/json lookups.
The module is written in C and Python, and cross-compiles on Linux and Windows. Underneath, it uses a radix tree
data structure for storage of IP addresses. In the current version, it borrows code from py-radix to support
both IPv4 and IPv6 network prefixes. The current release is a beta. Compared to the previous version,
adds new functionality, performance improvements, and unit-tests.