+-------------------------+--------------+---------+-------------------+
| 1\. DRD Title           | 2\. Date of  | 3\. DRL | RFP/Contract No.  |
|                         | current      | Line    | (*Procurement     |
| **Interface Control     |              |         | completes*)       |
| Document (ICD)**        | version      | Item    |                   |
|                         |              | No.     | NAS 9-18181       |
|                         | October 2001 |         |                   |
|                         |              | 25      |                   |
+-------------------------+--------------+---------+-------------------+
| 4\. Use (*Define need   |              |         | 5\. DRD category: |
| for, Intended use of,   |              |         | (*check one*)     |
| and/or anticipated      |              |         |                   |
| results of data*)       |              |         | x Technical       |
|                         |              |         |                   |
| Interface Control       |              |         | € Administrative  |
| Document (ICD) shall    |              |         |                   |
| both define and control |              |         | € SR & QA         |
| the physical and        |              |         |                   |
| software interfaces     |              |         |                   |
| between SSTF facility   |              |         |                   |
| and external NASA/other |              |         |                   |
| U.S.                    |              |         |                   |
| G                       |              |         |                   |
| overnment/International |              |         |                   |
| Partner facilities.     |              |         |                   |
+-------------------------+--------------+---------+-------------------+
| 6\. References          | 7\.          |         |                   |
| (*Optional*)            | Interr       |         |                   |
|                         | elationships |         |                   |
|                         | (*e.g., with |         |                   |
|                         | other DRDs*) |         |                   |
|                         | (*Optional*) |         |                   |
|                         |              |         |                   |
|                         | **26, 71**   |         |                   |
+-------------------------+--------------+---------+-------------------+

8\. Preparation Information (*Include complete Instructions for document
preparation*)

The ICD shall establish the interface specification for both software
and hardware,

and shall be binding on all parties involved. Physical interfaces shall
describe the

hardware interface, the data being transferred, and the communications
protocol.

Software (application to application) interfaces shall basically
describe the data being

transferred, the communications connectivity, and the control or
inter-operability

aspects which may affect the end design entities. The ICD shall be
developed in two

phases the preliminary containing the interface requirements and the
final

containing the interface design.

The interface requirements (preliminary) shall contain at least the
following

information.

A.  Purpose and function of the interface.

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B.  Total system information flow across the interface.

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C.  Error status and interface constraints.

D.  Included elements of commonality.

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E.  Identification of applicable standards.

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F.  Identification of responsibilities of participating organizations.

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G.  Interface requirements, and interface requirements traceability

> matrix.

The ICD (final) shall contain all of the above interface requirements
information and the following:

A.  Interface specification table to describe functional information,

> initiation criteria, and expected response.

B.  Logic level, data rates, control, timing (hardware and software),
    cable

> types, impedance, complete electrical and/or physical interface.
>
> However, software (application to application) IDC's may include
> cursory
>
> description of transparent transmission services and therefore will
> not
>
> require the detailed description of a hardware interface to the level
>
> delineated in this paragraph.

C.  Interface item table of describe the format of each item transmitted
    in

> terms of the byte position, data type , data rate, size, scaling,
>
> conventions, and content.