4Secure XML JSON Scanner
4XJS runs natively on the OPDS platform and can also run on some Linux flanking systems. In addition to XML and JSON schema checks, granular HTTP request filtering and compound schema filtering is is supported. 4XJS can work in conjunction with 4BDT in order to filter HTTP Responses.
4XJS is often used with an OPDS in order to design and implement a full cross domain solution with content filtering.