nd, 438 VTP domains, 56 no mls qos command, 340 VTP modes, 57 no redistribute igrp command, 152 VTP passwords, 58 no shutdown command, 224 VTP pruning, 61 no spanning-tree portfast command, 96 NYNEX, 351 no spanning-tree uplinkfast command, 98 no switchport command, 222, 427 no trouble found (NTF), 367 no vtp password command, 58 object groups, 475-477 no vtp pruning command, 59 object tracking, 194-196 no-more command (NX-OS), 278 object-group command, 476 Non-AAA authentication (see basic ODR (On Demand Routing), 107, 126 authentication) OFDM (Orthogonal Frequency-Division nonbroadcast multiaccess (NBMA) networks, Multiplexing), 512 On Demand Routing (ODR), 107, 126 none method, 454, 456 100Base-T, 20 nontriggered updates, 129 1000Base-T, 20 NRO (Number Resource Organization), 671 OOF (out-of-frame), 362 NSSA LSAs, 139 Open Shortest Path First (see OSPF) NTF (no trouble found), 367 optimum switching, 213 NTP (Network Time Protocol) option command, 537 about, 689 Orthogonal Frequency-Division Multiplexing accurate time considerations, 689-690 (OFDM), 512 OSPF (Open Shortest Path First) Index administrative distance, 107, 126 (see also authentication) bandwidth-based metrics, 124 best practices, 460 communication considerations, 121 line, 437-439 functionality, 137-143 VTP, 57 redistributing into, 154-156 PAT (Port Address Translation) routing tables and, 106 interface examples, 502-504 out-of-band signaling, 357, 359 NAT Overload and, 501 out-of-frame (OOF), 362 port redirection and, 504 overclocking, 377 reflexive access lists and, 431 oversubscription, 393 pattern matching, dial peers, 554 payload loopback, 367 Payment Card Industry (PCI), 643 PBX (private branch exchange), 350, 527 PA-A3-T3 module, 381 PCI (Payment Card Industry), 643 Pacific Bell, 351 PEAP (Protected Extensible Authentication packet loss, 531, 575 Protocol), 514 Packet Voice Digital Signal Processor (PVDM), peer keepalive links, 76, 296 Per-VLAN Spanning Tree (PVST), 91 packet-to-packet delay variation, 531 performance monitoring packets abo