Central Data Server [CDS]
CDS is the primary component of the MariWeb™
AIS suite of software and contains the primary active database along
with the AIS Service Management [ASM] functionality. The ASM has the
Services [BAS] as defined in the IALA A-124 Recommendation.
The ASM module also allows for the capture and testing of a complete network configuration definition according to the rules in the IALA A-124 Recommendation. This is done without downloading any of the data to the PSSs connected to the MariWeb™ AIS network. Once the network configuration has been downloaded to the MariWeb™ network or part thereof, a verify background task checks the configuration of the AIS Physical Shore Station [PSS] and nodes and alerts are generated when configuration changes.
AIS data is collected at the CDS from all of the AIS PSSs via the WAN, all duplicates are eliminated (except for the metadata), time stamped with time of arrival and source, verified and then stored in the Vessel Location Register [VLR]. The VLR is a high performance database and allows processing of the AIS data in real-time before storage in the primary SQL database (or other selected database) running on a COTS server.
AIS data can also be obtained from another database or data logging
system as an offline AIS data feed, from other AIS networks in IEC61162
or XML format or from a Lloyds Maritime Intelligence Unit [LMIU] or
similar data feed. MariWeb™
connections are normally RS232C, RS422 or TCP/IP. Where
UDP is required this is provided but not recommended due to the
‘fire and forget’ nature of UDP communications
methods and therefore lack of confirmed data delivery.
All incoming AIS data is stored in the primary database as an audit trail ensuring that all data is available in original (as received and not changed, processed or reconstituted) and in parsed format being human readable allowing export in Comma Separated Variable [CSV] format or XML via a Web Service or via an SQL query for further analysis. A ships database is available that stores all the static data for each vessel that is detected by the MariWeb™ system over its operational life. This provides an up to date record of all vessel fitted with AIS units and can be configured to raise an alert for the operator should the ships static AIS data change at any time.
The MariWeb™ CDS is protected by a complex firewall.