The present document addresses the requirements of network and service providers of Asynchronous Transfer Mode
(ATM) cross connected networks for managing the exchange of performance monitoring information associated with
the Virtual Path (VP) connections, which span several administrative ATM domains. These requirements are satisfied
by the use of a standardized interface (the "X-interface") between Operation Systems (OSs) belonging to different
Providing Network Operators (PNOs).
Readers of The present document should be made aware that the abbreviation PNO is taken to mean Providing
Network Operator. In early versions of other related documents EN 300 820-1 [7], EN 300 820-2 [8], PNO was defined
as Public Network Operator. The change in definition has been provided to reflect the change in market conditions for
provision of interconnected telecommunications services. However, it is considered necessary to retain the abbreviation
PNO because it is found in many of the managed object definitions used to specify the X-interface. It would be
disadvantageous to introduce major changes in these managed object definitions, which serve purely technical purposes
for management of interconnections only.
The present document should be used in conjunction with EN 300 820-1 [7] and EN 300 820-2 [8].
The present document describes the X-interface VP performance management area covering the following aspects:
the Management Services (MS) and Management Functions (MF) needed to provide the necessary management
messages for performance degradations detected within ATM connections and the necessaryManagement
Functions for co-ordination of performance monitoring;
the management information crossing the X-interface. This management information specification uses the
Guidelines for the Definition of Managed Objects (GDMO) formalism, described in
ITU-T Recommendation X.722 [11].