European digital cellular telecommunications system (Phase 2);Attachment requirements for Global System for Mobile communications (GSM) mobile stations;Telephony (Endorsed by Asociación Española de Normalización in February of 2022.)
Edition 2022-02-01

TERMINAL EQUIPMENT (TE). ATTACHMENT REQUIREMENTS FOR PAN-EUROPEAN APPRoval for connection to the analogue Public Switched Telephone Networks (PSTNs) of TE (excluding TE supporting the voice telephony service) in which network addressing, if provided, is by means of Dual Tone Multi Frequency (DTMF) singalling.
Edition 1998-09-29

DIGITAL CELLULAR TELECOMMUNICATIONS SYSTEM (PHASE 2). ATTACHMENT REQUIREMENTS FOR MOBILE STATIONS IN THE DCS 1800 BAND AND ADDITIONAL GSM 900 BAND. TELEPHONY.
Edition 1999-07-28

Digital cellular telecommunications system (Phase 2) (GSM);Attachment requirements for mobile stations in the DCS 1800 band and additional GSM 900 band;Telephony (Endorsed by Asociación Española de Normalización in February of 2022.)
Edition 2022-02-01

Telecommunications IP Telephony Equipment Voice Gateway Transmission Requirements
Edition 2015-08-05

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Edition 2009-02

Telecommunications IP Telephony Equipment Requirements for a Wireless LAN Based IP Telephony Endpoint
Edition 2008-02

Telecommunications IP Telephony Infrastructure Link Layer Discovery Protocol for Media Endpoint Devices
Edition 2006-04-06

Telecommunications Telephony Aspects of MLTS and Packetbased Equipment, including VoIP Interface Requirements for Packet-based Gateways
Edition 2006-04-15