The use of FTP for E-NP publications offers several advantages:

Even with official credentials, problems occur. Here is a troubleshooting guide for access.

To understand the FTP server’s role, you must first understand the products it serves.

The keyword phrase might look technical at first glance, but it represents the backbone of modern navigation safety. It signifies the exact method—File Transfer Protocol (FTP)—used by the UKHO to distribute critical updates to their digital products, specifically Electronic Navigational Publications (e-NPs) .

| e-NP Number | Title | Update Frequency | | :--- | :--- | :--- | | | The Mariner’s Handbook | Annual + Weekly corrections | | e-NP131 | List of Lights and Fog Signals (Vol A-P) | Weekly | | e-NP136 | Admiralty List of Radio Signals (ALRS) | Weekly (critical for GMDSS) | | e-NP201 | Admiralty Tidal Stream Atlas | Per Edition | | e-NP281 | Admiralty Tide Tables (ATT) | Annual + weekly adjustments | | e-NP735 | IMO & SOLAS Publications | As amended |

For maritime professionals, keeping nautical publications up to date is not just a matter of compliance—it is a cornerstone of safety of life at sea. The United Kingdom Hydrographic Office (UKHO) has long facilitated the distribution of digital updates for its range via a dedicated FTP (File Transfer Protocol) service.