This International Standard specifies the 8-contact connector (plug and jack) and the assignments of its contact
numbers for use in the physical interfaces of Integrated Services Digital Network (ISDN) primary rate access
services conforming to ITU-T Recommendation I.431.
In this International Standard, as in ITU-T Recommendation I.431, the term "NT" is used to indicate the network
terminating layer 1 aspects of NT1s and NT2s, and the term "TE" is used to indicate terminal layer 1 aspects of
TE1s, TAs and NT2s.
1 This International Standard specifies only those connector dimensions required to ensure intermatability of plug and
jack. Complete detailed specifications of the connector are the subject of IEC 603-7, see annex C.
2 ITU-T recognizes an alternative connection system which is not covered by this International Standard. It uses
coaxial connectors as specified in IEC 169-8 (see annex C), and is illustrated in annex B.