xix IPv6 DHCP ............................................................... 323 IPv6 in Windows 7, 8, and 10 .............................. 323 TCP/IP Troubleshooting Utilities ......................... 323 Netstat .................................................................... 323 Nbtstat ................................................................... 324 Ping ....................................................................... 325 Tracert or Traceroute ................................................. 326 ARP ....................................................................... 326 Nslookup ................................................................ 327 Tcpdump ................................................................ 327 CHAPTER 11 Subnetting .................................................................. 334 Binary Number System ......................................... 336 Dotted Decimal Notation ...................................... 336 Subnetting ............................................................... 337 Closer Look at Subnets ............................................. 340 Advantages of Subnetting .......................................... 342 Disadvantages of Subnetting ...................................... 342 Network Segmenting Devices .............................. 342 Bridge .................................................................... 343 Switch .................................................................... 343 Router .................................................................... 346 Virtual LAN.............................................................. 351 Static vs. Dynamic VLAN ........................................... 353 VLAN Trunking ........................................................ 353 Spanning Tree Protocol ............................................. 354 Classless Inter-Domain Routing .......................... 355 Link Aggregation .................................................... 356 CHAPTER 12 Additional Transmission Modalities ........................ 364 Voice and Audio Signals ....................................... 365 Signal Conversion .................................................... 366 Jitter ...................................................................... 369 Latency................................................................... 369 Acoustical Echo ....................................................... 370 Video ....................................................................... 371 Video Resolution ...................................................... 372 Compression ........................................................... 372 Other Transmission Protocols .............................. 373 X.25 ....................................................................... 373 Frame Relay ............................................................ 373 ATM ....................................................................... 374 VoIP.......................................................................379 Telephone Gateway and H.323 .................................... 381 Quality of Server (QoS) ............................................. 382 Session Initiation Protocol (SIP) ................................. 383 Real-Time Transport Protocol (RTP) ............................ 384 Basic VoIP Troubleshooting ................................. 385 Using a Protocol Analyzer to Verify Packet Exchange .......................................... 385 VoIP Jitter ............................................................... 386 Firewall Blocking VoIP Packets ................................... 386 Audio Device Configuration ....................................... 387 Impedance Mismatch ................................................ 388 CHAPTER 13 Web Servers and Services ........................................ 394 Internet, Intranet, and Extranet ........................... 395 Internet ................................................................... 395 Intranet ................................................................... 396 Extranet .................................................................. 396 Domain Name and URL Resolution .................... 396 Web Servers ........................................................... 397 Apache HTTP Server ................................................. 399 Internet Information Services (IIS) ............................... 400 Search Engines ...................................................... 401 Website Communication ....................................... 402 HTML .................................................................... 403 SGML .................................................................... 403 XML ...................................................................... 404 CSS ....................................................................... 404 JavaScript ............................................................... 405 SOAP ..................................................................... 405 File Transfer Protocol (FTP) ................................. 405 FTP Variations ......................................................... 407 Anonymous FTP Site ................................................ 407 Network News Transfer Protocol (NNTP) ............ 407 E-Mail ...................................................................... 409 Simple Mail Transfer Protocol (SMTP) ......................... 409 Post Office Protocol (POP) ........................................ 410 Internet Message Access Protocol (IMAP) .................... 410 Multipurpose Internet Mail Extensions (MIME) ............. 411 E-Mail Address Format ............................................. 411 E-Mail Structure ...................................................... 411 Mail Filter ............................................................... 412 Mail Gateway ........................................................... 413