Question 25/VII - Open Systems Interconnection (OSI) application layer
(continuation of part of Question 42/VII studied in 19851988 on OSI
application layer)

Considering

(a) that Recommendation X.200 specifies the reference model for Open
Systems Interconnection for CCITT applications;

(b) that Recommendation X.210 specifies the layer service definition
conventions of Open Systems Interconnection for CCITT applications;

(c) that Recommendation X.220 specifies the use of X.200-Series
protocols in CCITT applications;

(d) that Recommendations X.217 and X.227 specify the association control
service and protocol of Open Systems Interconnection for CCITT
applications;

(e) that administrations and users in many countries are applying the
Open Systems Interconnection family of Recommendations to public
networks now existing or due to be available in the near future;

(f) that close collaboration and liaison with other international bodies
(e.g., ISO, IEC) studying Open Systems Interconnection is highly
desirable,

therefore, work should continue to determine:

1. Application layer

a) What further study is required to extend the services and protocol of
the association control Recommendations X.217 and X.227 to provide
additional capabilities, such as application context management and
authentication control?

b) What is required to further develop application layer structure,
services and protocols having wide applicability among various different
CCITT applications?

In particular, studies should include:

i) application layer structure;

ii) commitment, concurrency and recovery;

iii) OSI transaction processing;

iv) impact of distributed processing work on application layer
structure, services and protocols;

v) impact of security considerations on application layer services and
protocols;

vi) impact of management considerations on application layer services
and protocols;

vii) formal description of application layer services and protocols;

viii) validation of application layer protocol specifications to avoid
potential errors.

c) What is required to provide for registration of information objects
of concern to these application layer services and protocols?

2. Liaison

What is necessary to maintain cooperation with other international
organizations (e.g., ISO/IEC JTC 1) in activities concerning the
application layer for OSI?