Minimal OSI Upper-Layers
charter-ietf-thinosi-01

The OSI upper-layer protocols (above transport) are rich in function
and specified in large, complex and numerous documents. However, in
supporting a particular application, the protocol actually used is only
a subset of the whole. An implementation is not required to support
features it never uses, and it is, or should be, possible to have
relatively lightweight implementations specialized for a particular
application or group of applications with similar requirements. The
application protocol could be an OSI application layer standard or a
protocol originally defined for TCP/IP or other environment. It will be
easier to produce such implementations if the necessary protocol is
described concisely in a single document.

An implementation, of the mapping of X Window System protocol over OSI upper-layers, is based on this principle.

The working group is chartered to produce two documents:

``Skinny bits for byte-stream'': a specification of the bit
sequences that implement the OSI upper-layer protocols (session,
presentation and ACSE) as needed to support an application that
requires simple connection, and byte-stream read and write. This will
be based on the octet sequences needed to support X. This will not be
expected to be provide a full equivalent of TCP, nor to cover specific
standardized protocols.

``Skinny bits for Directory'': a specification of the bit sequences
needed for the Directory Access Protocol - in the same style as the
byte-stream specification, but to include DAP. The level of functionality
of this is to be determined.

An important aspect of the group's work is to find out if it is possible
to produce useful and concise specifications of this kind. A minor part
is to think of better names.

The group will also encourage the deployment of X/OSI implementations
and interworking experiments with it.