Yealink SIP-T21 E2

Introduction
xvii
 Customizing Softkey Layout Template File on page 289
 Dial Plan using Digit Map String Rules on page 315
 Call Number Filter on page 516
 Calling Line Identification Presentation (CLIP) on page 532
 Intercom on page 543
 Lightweight Directory Access Protocol (LDAP) on page 591
 Visual Alert and Audio Alert for BLF Pickup on page 611
 Server Redundancy on page 749
 Audio Codecs on page 854
 Methods of Transmitting DTMF Digit on page 891
 Appendix C: Trusted Certificates on page 1012