Jeppesen Marine has launched a new updating service that can transmit Notices to Mariners, new charts and new chart editions to ships at sea, all via a high-speed Internet connection. The service, called C-MAP Updating Service Online+, applies to Jeppesen Marine's C-MAP Professional+ and C-MAP ENC chart database subscribers. The key to this new updating service is Jeppesen's distribution format, called C-MAP CM-93/3 and type approved by DNV. This format can compress large amounts of navigational data to a size that makes online transmission rapid and reliable. Ships will need to download only 6 MB to 9 MB of data per week (for global coverage) for the C-MAP ENC database, and substantially less for C-MAP Professional+.