The Real Estate Transaction Standard (RETS) facilitates data transfer between partners in the real estate industry via XML/webservice calls. It is an improvement over the existing protocol/procedure called IDX (Internet Data exchange) which could mean HTTP webservices, CSV files from FTP, or in some cases via Telnet.
RETS is a standardized and Realtor Association of America backed protocol meant to help consolidate and simplify the process of a multiple listing service organization providing access to their respective real estate date. Part of this standardization process was the creation of a standard naming convention and schema for data, which is still in progress.
References and useful links
The libRETS API library, a developer resource, is available. LibRETS is a C++ library with SWIG native bindings for .NET, Java, Perl, PHP 5, Python, and Ruby.
Rapattoni was one of the first MLS service providers to provide RETS support and fortunately they have extensive support documentation that can be applicable to other RETS servers.
PHRETS open source PHP library for using RETS. PHRETS provides PHP developers a way to integrate RETS functionality directly within new or existing code. A standard class of functions is made available to developers to connect and interact with a server much like they would with other APIs.
