DISA

1. Direct Inward System Access. A PBX feature that allows remote access to the system, generally on a toll-free basis.The caller dials the telephone number associated with a special DISA trunk. After the PBX answers the call, the caller can gain access to connected resources by entering the proper authorization codes. DISA is useful to authorized users requiring remote access to e-mail servers, voice processors, computer systems, and outgoing toll trunks. However, DISA may open the system and all connected resources to hackers, who often target them in order to gain unauthorized access to the same resources.

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• Conférence Européenne des administrations des Postes et des Télécommunications (CEPT)
• congestion
• congestion management
• conjugate structure algebraic code excited linear prediction (CS-ACELP)
• connection
• connectionless
• Connectionless Broadband Data Service (CBDS)
• Connectionless Network Protocol (CLNP)
• connection-oriented
• connector
• Consent Decree
• console
• Consortia, Fora, and Special Interest Groups (SIGs)
• Consortia, Fora, and Special Interest Groups (SIGs)
• Consortia, Fora, and Special Interest Groups (SIGs)
• constant bit rate (CBR)
• constraint-based routing
• Consultative Committee for International Telephone and Telegraph (CCITT)
• content blocking
• continuity algorithm
• continuously variable slope delta modulation (CVSDM)
• continuously variable slope delta modulation (CVSDM)
• continuous redial
• continuous redial
• contraction