<html><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><span class="Apple-style-span" style="font-family: verdana, geneva, helvetica, arial, sans-serif; font-size: 13px; border-collapse: collapse; ">Hello Vinod and Franck, <br><br>Actually, SENC stands for System ENC. <br>SENC are the internal chart database proprietary formats specific to the different developers of ECS (Electronic Chart System) or ECDIS (Electronic Chart Display and Information System) software applications, created from decrypted ENC files which can be in non protected s-57 open exchange format (used by NOAA) or in s-63 encrypted format, IHO (International Hydrographic Organization) Data Protection Scheme for the protection of ENC information by most of the other Hydrographic Services and distributed by Primar and IC-ENC. <br>s-63 defines security constructs and operating procedures that must be followed to ensure that the data protection scheme is operated correctly and to provide specifications that allow participants to build compliant systems. <br>Regarding s-63 implementation, see : <br><a href="http://www.iho-ohi.net/english/about-encs/enc-data-protection/implementing-the-iho-security-scheme.html" target="_top" rel="nofollow" style="font-size: 1em; ">http://www.iho-ohi.net/english/about-encs/enc-data-protection/implementing-the-iho-security-scheme.html</a><br><br>Best regards <br><br>-- <br>Peio Elissalde </span> <br></body></html>