HDLC (High-Level Data Link Control)

A bit-oriented, synchronous data communications proto-

col developed by the International Organization for Standardization (ISO) as a superset of Synchronous Data Link Control (SDLC) and Advanced Data Communications Control Procedures (ADCCP). A version of HDLC is the Link Access Procedure-Balanced (LAPB), which is used in packet-switched networks conforming to the ITU-T X.25 Recommendation. HDLC also was imported into other standards, including ISDN as LAPD and frame relay as LAPF. See also ADCCP, bit-oriented protocol, frame relay, ISDN, ISO, LAPB, LAPD, LAPF, SDLC, synchronous, and X.25.

• delta modulation
• demand assigned multiple access (DAMA)
• demarcation point
• demarc (demarcation point)
• demod/remod (demodulation/remodulation)
• demodulate
• dense wavelength division multiplexing (DWDM)
• DES (Data Encryption Standard)
• deterministic
• DFB laser (Distributed FeedBack laser)
• DFB laser (Distributed FeedBack laser)
• DFB laser (Distributed FeedBack laser)
• DFS (Dynamic Frequency Selection)
• DG XIII (Directorate General XIII)
• DHCP (Dynamic Host Configuration Protocol)
• dial
• dial around
• dialed number identification service (DNIS)
• dial tone
• dial-up access
• dial-up circuit
• dibit
• DID (Direct Inward Dial)
• dielectric
• dielectric