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+# BE70: Backend extension specification
+
+| name                       | BE70               |
+|----------------------------|--------------------|
+| version                    | 0.1.1(preview)     |
+| status                     | proposal           |
+| authors                    | Tom Harley (trh)   |
+| serving component(s)       | all                |
+| consuming component(s)     | all                |
+| basic spec                 | no                 |
+| can be required by servers | no                 |
+| can be required by clients | yes                |
+
+The key words "**MUST**", "**MUST NOT**", "**REQUIRED**", "**SHALL**", "**SHALL NOT**", "**SHOULD**", "**SHOULD NOT**", "**RECOMMENDED**", "**MAY**", and "**OPTIONAL**" in this document are to be interpreted as described in [RFC 2119](https://www.ietf.org/rfc/rfc2119.txt).
+
+## Changelog
+### Version 0.1
+
+- First draft
+
+## Dependency
+This protocol relies on [Protocol BE01](BE01.md), in particular [the section on using tokens](BE01.md#using-tokens).
+
+## Authorisation Token
+A device requiring authorisation **MUST** accept an `Authorization` token (if present) as if it were an `Authorisation` token.
+
+Devices presenting authorisation **MAY** include both an `Authorisation` token and an `Authorization` token, however in this case both tokens **MUST** have identical contents.