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Amver-A Look Behind the Blue and White Pennant

By Gary A Burke, Jr., Amver Applications Programmer II, USCG Operations System Center

Most mariners will instantly recognize the name Amver. For those who do not, the Amver system is a U.S. Coast Guard sponsored search and rescue (SAR) program. Participation in Amver is voluntary, and information is protected and used only in a bona fide maritime emergency. The Amver system consists of over 12,000 vessels from over 140 nations. This global participation allows Amver to be known as the only worldwide SAR system to date, unlike Japan and Australia who have their own vessel reporting systems, but the coverage area is limited to that country. Our participants faithfully report their vessel's movements, but very few mariners know what happens to their data once sent or the process by which it enters the Amver database.

To start our journey, let's first look at where the Amver system currently resides. The Amver system and its support staff are located at the U.S. Coast Guard's Operations System Center (OSC) in Martinsburg, West Virginia. No matter where vessels are in the world, their Amver message will ultimately be received at OSC. At OSC the Amver system is tagged with a "mission critical" status, meaning the Amver staff is required to maintain 99.5% system availability for our users. The Amver staff is on call 24 hours a day, 7 days a week to resolve any message traffic or system problems. The system is routinely taken down for regularly scheduled maintenance, which does not count against our 99.5% system availability. Even though the system is unavailable to users during this 8-10 minute time frame, Rescue Coordination Centers (RCCs) can call OSC where we have the ability to run a Surface Picture (SURPIC) of the distress location through a "hot-wired" laptop and provide the RCCs with accurate Amver information. The Amver system has full system redundancy with a production server and "hot" backup server that mirrors production. A third "test" server allows the staff to completely test any new technology as if it were in the production environment.

Now you know where vessel messages go, let's look at how they get here. Nearly all Amver message traffic is received at OSC via e-mail; the only exception being a small number of faxed messages. The Amver program has an "e-mail solution" in place with all of the participating traffic providers, so if a vessel is sending reports via ATT telex or AmverSeas, the e-mail solution will forward the report to OSC. Vessels can also send e-mail reports directly to OSC via the ship's Internet Service Provider (ISP). The message must be addressed to amvermsg@amver.com and reports should be sent in plain text in the body of the e-mail.

What about e-mail viruses, junk mail and SPAM? Not a problem. All e-mail passes through the Coast Guard's mail hub, which scans every e-mail using the latest virus definition. Filtered and cleaned, the e-mail then must be accepted by our procmail instance. Procmail is Amver's own personal address book of valid senders. If a sender is not in our procmail file, the e-mail message will be sent to a rejects directory. The rejects directory is checked several times a day, and rejected messages are researched and determined to be valid or bogus. For valid messages a new entry will be made to the procmail file, which will allow the next message received to be processed normally. Bogus senders are rejected outright.

Junk e-mails and SPAM can be blocked with a simple entry into Amver's amprc file. The amprc file is a vital part of Amver's e-mail delivery process. Not only can it block junk e-mail and SPAM, amprc also allows Amver to sort out emergency/distress messages for immediate action. Somewhat similar to procmail, amprc contains a listing of "attention keywords" like distress, immediate, fire, etc. Amprc will review each Amver report looking for specific keywords. If a keyword is received, the delivery process will "kick" the report out to Amver's attention directory. The attention directory is monitored every 7 minutes. If the directory contains a report, an audible alarm sounds in the Amver watch. The Amver Analyst determines if there is a real distress and routes the message accordingly. For junk e-mail and SPAM it's the same process, except when a "junk" message is found the report is rejected immediately without Analyst intervention.

Now the delivery process is complete, the reports must be parsed. In May 2002 the Amver Team completed the final stage of its message parser re-write. When the new automated message parser (AMP) rolled into production in May 2002, Amver took a giant leap forward. Amver's new parser incorporates the new e-mail technology with message correcting capabilities and, most importantly, automation of data entry. Prior to May 2002, every Amver message was reviewed and entered by an Amver Analyst. When AMP rolled into production approximately 65 percent of all message traffic was getting entered automatically. AMP also employs message-correcting capabilities. Even though all Amver reports are supposed to be in the International Maritime Organization (IMO) standard format, many need to be fixed. To combat this AMP has a "fix general" routine that will remove imbedded spaces, carriage returns, and correct simple formatting errors within the message. From there AMP performs a "fix by line" routine. Each specific line of an Amver IMO standard report has a routine. When building the parser we compiled a list of bad report formats for each line and incorporated this into AMP's "fix by line" routine, fixing each bad report format. Message correction is done within seconds of the message being received from the delivery process.

Even though AMP is now processing the majority of the 3900+ Amver messages received daily, the parser relies on the Amver Analysts to remain effective. For example, when validating a sail plan, AMP will first try and use the information provided by the vessel. AMP reiterates through several processes to determine if this information is accurate and if the turn points are correct. If AMP determines the information is not correct, it will look into the database to see if the vessel has any similar voyages that match the current route and use the one with the least amount of deviation. If AMP cannot find a similar voyage in the vessel's history, it will reference all previously committed routes in the database and use the one with the least amount of deviation. At this point if no route is found, AMP will pass the message on to the Amver Analysts. Once the Amver Analyst enters the route, it will be available for AMP to use the next time a similar voyage is received.

AMP will try and enter every report it receives with the exception of a deviation report. Every deviation report sent to Amver is passed to the Analysts for entry. Most deviation reports received lack the detailed information needed to have AMP enter them correctly. For all other report types, several different validation checks are built into AMP, which will have to be met in order to process the report. If AMP should fail to meet any of our validation checks, it will not process the report and the report is passed to the Amver Analysts. One example is a deviation check. If AMP determines a vessel's deviation exceeds more than 50 nmi off our predicted track, it will pass the report to the Analysts. Another example is a report missing required information, such as a position report without a current speed or time.

AMP is kept accurate by the Amver Analysts who extensively research all route discrepancies and reporting errors to determine the best possible solution. All these validation checks ensure the messages are correct and AMP remains accurate.

Once vessel messages have been entered, the information is released onto the active plot. On the active plot, Amver continually positions the vessel in time. Using dead reckoning, Amver will continue to move the vessel along its intended track using the reported speed and course until the next update from the vessel is received. So when the Rescue Coordination Centers (RCCs) access Amver information for a SAR case, the information they receive will be a listing of all the vessels within the distress area using Amver's last known good update. This plot information is updated every hour to keep the information as close to real time as possible.

Now you've seen what goes on behind the scenes, hopefully you'll have a better understanding of the Amver system. If you have any questions about Amver or would like to learn more about the Amver system check out our web site at www.amver.com. The entire Amver staff at OSC Martinsburg would like to wish all our mariner friends our best wishes for continued safe passage abroad.

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