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+# exchange-set-service
+
+The Exchange Set Service will allow distributors to request custom exchange sets, built to the [S-63 specification](https://en.wikipedia.org/wiki/S-63_(encryption_standard)) for delivery of ENC data to vessels.
+
+An exchange set is defined in the [IC-ENC Glossary](http://www.ic-enc.org/Glossary.html) as:
+
+> An exchange set is a grouping of data sets in a logical, consistent and self-contained collection to support the interchange of geospatial data and meta data.
+
+Read more in the full [IHO S-63 Specification](https://iho.int/uploads/user/Services%20and%20Standards/ENC_ECDIS/data_protection/S-63_e1.2.0_EN_Jan2015.pdf).
+
+An exchange set can be loaded into an ECDIS (Electronic Chart Display and Information System) on a vessel for navigation planning.
+
+## Viewing the API Spec
+
+Rather than reading the OpenAPI specification in raw form, copy the API specification YAML file into [an online Swagger editor](https://editor.swagger.io/) for a rendered view.
+
+## Calling the Exchange Set Service
+
+*Note that this section is draft, based on what we are doing for the [File Share Service (FSS)](https://github.com/UKHO/file-share-service/)*
+
+### Using ESS in Postman
+
+To generate an authorization token in Postman follow these steps:
+
+#### Get Authorization for the environment's App Registration
+
+Ask Calypso (or service Owner) to give you Roles for the ESS App Registration:
+
+* `ESS-API-DEV`
+* `ESS-API-QA`
+* `ESS-API-LIVE`
+
+#### Select OAuth2.0
+
+Select `Oauth 2.0` in the authorization tab.
+
+![OAuth2 Postman Section](/Documentation/Images/PostmanAuthTabOauth.PNG)
+
+#### Fill in the OAuth section, click get new access token, login from the popup window
+
+Grant Type - Implicit
+
+Auth URL - `https://login.microsoftonline.com/9134ca48-663d-4a05-968a-31a42f0aed3e/oauth2/v2.0/authorize`
+
+Client ID:
+
+| Environment | Client ID |
+| -- | -- |
+| DEV | 80a6c68b-59aa-49a4-939a-7968ff79d676 |
+| QA | 644e4406-4e92-4e5d-bdc5-3b233884f900 |
+| LIVE | fd4cb7ab-ed8f-4398-bafa-4f83284febbe |
+* QA ### TBC ###
+* LIVE ### TBC ###
+
+Scope:
+
+| Environment | Scope |
+| -- | -- |
+| DEV | 80a6c68b-59aa-49a4-939a-7968ff79d676/.default |
+| QA | 644e4406-4e92-4e5d-bdc5-3b233884f900/.default |
+| LIVE | fd4cb7ab-ed8f-4398-bafa-4f83284febbe/.default |
+* QA ### TBC ###/.default
+* LIVE ### TBC ###/.default
+
+NOTE: The browser used to authenticate needs to allow popups!
+
+![OAuth2 Postman Section](/Documentation/Images/PostmanAuthTabOauthDetails.PNG)
+
+#### Update the token
+
+Paste the token into the `Access Token` field at the top of the Postman OAuth2 section.