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USCG COMDTINST 5230.80 sets forth the following levels of NAIS real-time (feeds) and historical data that the USCG may provide, to which entities it may be provided to, and our request procedures.

NAIS data may not be retransmitted, shared, used for commercial or other purposes than as approved by the USCG.

Real-Time Data Feed Requests - Level A and Level B
Level A is unfiltered real-time data that is less than 96 hours from initial time of transmission.  Level A information may only be shared with U.S. or foreign government agencies (“Level A Entities”) for legitimate internal government use. 
Level B is filtered real-time data that is less than 96 hours from initial time of transmission, which may be shared with the “Level B Entities” below:
(a) Foreign governments or U.S. Federal, State, local and tribal government agencies;
(b) Non-governmental entities that are contractually supporting a Federal government agency’s operations or research and development efforts (with proper documentation);
(c) USCG-validated port partners (with proper documentation); and
(d) Non-governmental entities with which the U.S. has an established or formalized relationship.

For real-time data feed requests, please complete and submit the Data Feed Request Form.  Once approved, the requestor will be required to complete an Interconnection Security Agreement (ISA) with the Coast Guard. The ISA defines the terms and conditions for data sharing between the customer and Coast Guard.

Basic user support related to NAIS connectivity will be provided. Initial customer support is limited to providing software required for connection. Please note that the data provided is in NMEA version 4 format and viewing software is not provided. All other support-related questions or concerns should be referred to your local IT support staff.

1. Minimum hardware necessary to run connection software:

- PC with a 1.5Ghz P4 processor or higher
- 1GB RAM or greater
- Linux, Windows, or Solaris Operating System, and
- J2SE 1.4.1 or greater

2. Minimum bandwidth required for each real time feed (in Kb/s):

- Unique Port (8303) with compression: ~2100Kb/sec
- Standard/Full Port (8304) with compression: ~2400Kb/sec
- Timed Port (8305) with compression 650Kb/sec
Historical Data Requests (HDR) – Level C

Level C is filtered and unfiltered historical data that is more than 96 hours from initial time of transmission.  According to the USCG COMDTINST 5230.80 only requests from “Level A Entities” and “Level B Entities” should be submitted via this website. NOTE: HDRs from non-governmental “Level B Entities” submitted via this website will be reviewed and granted in accordance with the Freedom of Information Act (FOIA), 5 U.S.C. §552. 

All other public requests for historical data will only be accepted via the FOIA process which you can submit via the following webpage  Please review our "FOIA AIS Data Information" web page for information that should be included in your written FOIA request.

For a HDR, please complete and submit the Historical Request Form.