# Recommendation I.412 (11/1988): ISDN user-network interfaces - Interface structures and access capabilities

> recommendation/international standard from the International Telecommunication Union

**Wikidata**: [Q27051418](https://www.wikidata.org/wiki/Q27051418)  
**Source**: https://4ort.xyz/entity/recommendation-i-412-11-1988-isdn-user-network-interfaces-interface-structures-and-access-capabilities