ITU-T G.823

ITU-T G.823 PDF

The control of jitter and wander within digital networks which are based on the 2048 kbit/s hierarchy.

This ITU-T Recommendation specifies the relevant parameters and their limiting values that are able
to satisfactorily control the amount of jitter and wander present at Network Node Interfaces (NNI) of
Plesiochronous Digital Hierarchy (PDH) and synchronization networks which are based on the firstlevel
hierarchical bit rate of 2048 kbit/s.
This ITU-T Recommendation also specifies the jitter and wander requirements at PDH
User-Network Interfaces (UNI). However, particular terminals or services may have additional jitter
and wander requirements and in those cases the relevant ITU-T Recommendations shall apply.
Requirements for NNI of PDH and synchronization networks which are based on the first-level
hierarchical bit rate of 1544 kbit/s are specified in ITU-T Recommendation G.824 and requirements
for Synchronous Digital Hierarchy (SDH) NNI are specified in ITU-T Recommendation G.825.
The jitter and wander requirements specified in this ITU-T Recommendation are applicable to the
interfaces irrespective of the underlying transport mechanism (PDH, SDH or ATM networks, for
example).
The jitter and wander requirements for an interface will be different, depending on whether the
signal at the interface is used to transport traffic and/or synchronization. The requirements for both
traffic and synchronization interfaces are specified in this ITU-T Recommendation in the appropriate
clauses.
A synchronization network that conforms to the network limits for jitter and wander specified in this
ITU-T Recommendation will be suitable for the synchronization of SDH and Public Switched
Telephone Network (PSTN) networks.
This ITU-T Recommendation also specifies the jitter and wander requirements for interfaces using
the generic frame structures at PDH rates as defined in ITU-T Recommendation G.832.
The electrical characteristics of the relevant PDH network interfaces are defined in ITU-T
Recommendation G.703.
The jitter and wander control philosophy of this ITU-T Recommendation is based on the need:
a) to specify a maximum network limit of jitter and wander that shall not be exceeded at any
relevant interface;
b) to specify a minimum equipment tolerance to jitter and wander that shall be provided at any
relevant interface;
c) to establish a consistent framework for the specification of individual digital equipment
types; and
d) to provide sufficient information and guidelines for organizations to measure and study jitter
and wander characteristics in any network configuration.