---
title: c-InternationalISDNNumber
description: ISDN address for a collection of entries.
component: pingds
version: 8.1
page_id: pingds:schemaref:at-c-InternationalISDNNumber
canonical_url: https://docs.pingidentity.com/pingds/8.1/schemaref/at-c-InternationalISDNNumber.html
---

# c-InternationalISDNNumber

ISDN address for a collection of entries.

|                             |                                                                      |
| --------------------------- | -------------------------------------------------------------------- |
| *OID*                       | 2.5.4.25.1                                                           |
| *Names*                     | c-InternationalISDNNumber                                            |
| *Superior type*             | [internationaliSDNNumber](at-internationaliSDNNumber.html)           |
| *Syntax*                    | [NumericString](s-NumericString.html)                                |
| *Equality matching rule*    | [numericStringMatch](mr-numericStringMatch.html)                     |
| *Ordering matching rule*    | [numericStringOrderingMatch](mr-numericStringOrderingMatch.html)     |
| *Substring matching rule*   | [numericStringSubstringsMatch](mr-numericStringSubstringsMatch.html) |
| *Single value*              | false: multiple values allowed                                       |
| *Collective*                | true                                                                 |
| *User modification allowed* | true                                                                 |
| *Usage*                     | userApplications                                                     |
| *Origin*                    | [RFC 3671](https://datatracker.ietf.org/doc/html/rfc3671)            |
| *Schema file*               | 00-core.ldif                                                         |