Publication Data Updates (PDU)

 

 

What is a PDU?

Publication Data Updates (PDU) are small binary patch files (<1 Mb) which, when applied to the current baseline of a Digital Nautical Publication (DNP), will bring that publication up-to-date with all outstanding corrections. These corrections include, but are not limited to, U.S. Notice to Mariner changes (textual and graphic) as well as compilation analysis changes that previously only appeared in the next new edition. In short, all updated information as of the date of the PDU is included. With PDU, Digital Navigation Publications will contain more extensive and timely maritime safety information for the use of our customers.

Starting 1 October 2002, all navigation publication new editions will be produced in digital format only. All publications are available on the Digital Nautical Publications – Quarterly Update or on the Maritime Safety Information website. Publication Data Updates are available for Digital Navigation Publications in a WinZip archive file, located on the same Web page where the publication files are accessed.  There are two possible types of updates available; sequential or cumulative.

·        Sequential updates apply to the entire publication and must be applied in date order (i.e., oldest to newest).

·        Cumulative updates are larger files that include all the sequential updates and allow the user the option of downloading and installing all sequential updates at once.

 

IMPORTANT NOTES:

  • NGA's transition away from hardcopy publications in favor of digital medium will be a phased-in process. Current hardcopy publications will remain in effect until replaced by a new edition DNP and will continue to be updated via the U.S. Notice to Mariners. PDU will only be generated for those publications generated as DNP (new editions after 1 Oct 2002).
  • PDU CANNOT be applied to previous (old) editions of a Digital Nautical Publication. You will receive error messages when trying to apply an invalid update and the publication will not be updated.
  • For sequential PDU's, each update will build on the previous one. This ensures that the updates remain small while ensuring the most comprehensive and up-to-date product for our customers.

 

System Requirements:

Any personal computer (PC) running Windows 9X, Windows ME, Windows 2000, Windows NT, or Windows XP.

How is it used?

Download Instructions:

  • On the website, locate the publication you wish to check for updates.
  • Some publications have the updates on the same page as the publication, but as for the case of Sailing Directions, you have to choose the publication under “Digital Updates”, if Sailing Direction pub you are looking for is not in “Digital Updates” means there are no updates for that publication.
  • Right-click on the update you want to download.
  • Select Save Link As (Netscape Navigator) or "Save Target As" (Microsoft Internet Explorer).
  • Specify the location where you want to save the publication update on your local hard disk.
  • Select "Save."
  • The file will be downloaded to your local hard disk.
  • Unzip the executable file using a program such as WinZip, PKUNZIP, etc.

Applying the Update:

  • Double-click the executable file.
  • Welcome screen will appear.
  • The PDU will search your computer automatically in order to locate where you installed the publication.
  • If you installed it in the default location, it will be found in C:\NGA_Data\Pub_###\SDPUB###.
  • Click "Yes" to acknowledge the correct location.
  • The publication will now be updated accompanied by a horizontal status meter displaying the progress of the update.
  • Upon PDU completion a dialogue window will be displayed stating "Pub ### has been successfully updated..." Click "OK" to acknowledge.

Verifying the Update:

  • Click on the "Start" button.
  • Navigate to NGA_Data, Sailing Directions, Pub ###, Pub ### (pdf file).
  • After the PDF file opens, a dialogue window will appear stating "Publication ###, is correct through PDU # - ## ### 200#." Click "OK" to acknowledge.
  • To locate where changes occurred throughout the publication a change bar was added to the left of the data to indicate a change has taken place. Note: If information was removed from the file, such as an entire paragraph, there may be no indication of that change.

Sign Up for the Publication Data Updates (PDU) via E-Mail

 

As a service to our customers who experience difficulty accessing the Internet, NGA now provides a service whereby Publications Data Updates (PDU) and notification of publication new editions are delivered via e-mail message to the requesting address.

 

Subscribers to this service should be aware that many networks have restrictions on the maximum file size of an e-mail attachment. To ensure that all PDU files can be received, the file size limit for the receiving account should accommodate a 2.5 MB file. Users may need to contact a network administrator for assistance.

 

PDU files transmitted are also posted on the Maritime Safety Information (MSI) Website at

http://www.nga.mil/portal/site/maritime/ in the “Publications” section.

 

To enroll in the Publication Data Updates Subscription Service, send a blank e-mail to join-pdu@goldweb.nga.mil from the account where you wish to receive the files.

 

A confirmation e-mail will be sent to the requesting account from NGA’s subscription service provider. USERS MUST RESPOND TO THE CONFIRMATION E-MAIL TO ACTIVATE THE SUBSCRIPTION. Once confirmation is received, another e-mail is sent to notify the user that the subscription has been activated.

 

Instructions for discontinuing the subscription service are included in each Publication Data Updates e-mail.

 

< a>Sample PDU file

Sample PDU file