network protocols handbook.pdf

More documents

Recommendations

Info

140Protocols GuideVoice Over IP(VOIP) - Media / CODECRelated protocolsRTP, RTSP, H.323, H.225Sponsor SourceG.7xxis a suite of ITU-T (http://www.itu.int/ITU-T/ ) standards.Referencehttp://www.h323forum.org/papers/H.323 papers and documents
141Protocols GuideVoice Over IP(VOIP) - Media / CODECProtocol NameH.261: Video Coding and Decoding(CODEC)Protocol DescriptionH.261 is the video coding standard of the ITU. It was designedfor data rates which are multiples of 64Kbit/s and is sometimescalled p x 64Kbit/s (p is in the range 1-30). These data rates suitISDN lines, for which this video codec was originally designed.H.261 transports a video stream using the real-time transportprotocol, RTP, with any of the underlying protocols that carryRTP.The coding algorithm is a hybrid of inter-picture prediction,transform coding and motion compensation. The data rate of thecoding algorithm was designed to be able to be set to between40 Kbits/s and 2 Mbits/s. INTRA coding encodes blocks of 8x8pixels each only with reference to themselves and sends themdirectly to the block transformation process. On the other hand,INTER coding frames are encoded with respect to another referenceframe. The inter-picture prediction removes temporalredundancy. The transform coding removes the spatial redundancy.Motion vectors are used to help the codec compensatefor motion. To remove any further redundancy in the transmittedbitstream, variable length coding is used.H261 supports motion compensation in the encoder as an option.In motion compensation a search area is constructed inthe previous (recovered) frame to determine the best referencemacroblock.H261 supports two image resolutions, QCIF (Quarter CommonInterchange format) which is (144x176 pixels) and CIF (CommonInterchange format), which is (288x352).The video multiplexer structures the compressed data into ahierarchical bitstream that can be universally interpreted. Thehierarchy has four layers:1. Picture layer: corresponds to one video picture (frame)2. Group of blocks: corresponds to 1/12 of CIF pictures or1/3 of QCIF3. Macroblocks : corresponds to 16x16 pixels of luminanceand the two spatially corresponding 8x8 chrominancecomponents.4. Blocks: corresponds to 8x8 pixelsProtocol StructureH.261 Header Structure:• SBIT - Start bit. Number of most significant bits thatare to be ignored in the first data octet.• EBIT - End bit. Number of least significant bits thatare to be ignored in the last data octet.• I - INTRA-frame encoded data field. Set to 1 if thisstream contains only INTRA-frame coded blocks andto 0 if this stream may or may not contain INTRAframecoded blocks.• V - Motion Vector flag. Set to 0 if motion vectors arenot used in this stream and to 1 if motion vectors mayor may not be used in this stream.• GOBN - GOB number. Encodes the GOB number ineffect at the start of the packet. Set to 0 if the packetbegins with a GOB header.• MBAP - Macroblock address predictor. Encodes themacroblock address predictor (i.e., the last MBA encodedin the previous packet). This predictor rangesfrom 0 to 32 (to predict the valid MBAs 1-33), but becausethe bit stream cannot be fragmented betweena GOB header and MB 1, the predictor at the start ofthe packet can never be 0.• QUANT - Quantizer field. Shows the Quantizer value(MQUANT or GQUANT) in effect prior to the start ofthis packet. Set to 0 if the packet begins with a GOBheader.• HMVD - Horizontal motion vector data field. Representsthe reference horizontal motion vector data(MVD). Set to 0 if V flag is 0 or if the packet beginswith a GOB header, or when the MTYPE of the lastMB encoded in the previous packet was not MC.• VMVD - Vertical motion vector data (VMVD). Referencevertical motion vector data (MVD). Set to 0 if Vflag is 0 or if the packet begins with a GOB header,or when the MTYPE of the last MB encoded in theprevious packet was not MC.Related protocolsRTP, RTSP, H.248, H.323, H.225, H.245, H.263Sponsor SourceH.261 is an ITU-T (http://www.itu.int/ITU-T/ ) standards.Referencehttp://www.javvin.com/protocol/rfc2032.pdfRTP Payload Format for H.261 Video Streamshttp://www.h323forum.org/papers/H.323 papers and documents3 6 7 8 12 17 22 27 32bitSBIT EBIT I V GOBN MBAP QUANT HMVD VMVD
Page 1 and 2:
www.dbeBooks.com - An Ebook Library
Page 3 and 4:
ITable of ContentsTable of Contents
Page 6 and 7:
IVTable of ContentsCR-LDP: Constrai
Page 8 and 9:
VITable of ContentsCOPS: Common Ope
Page 10 and 11:
VIIITable of ContentsGARP: Generic
Page 12 and 13:
XTable of ContentsIGRP: Interior Ga
Page 14 and 15:
XIIFigureFigureFigure 1-1: Communic
Page 16 and 17:
XIVPerfacePrefaceWe are living in t
Page 18 and 19:
2Network Communication Architecture
Page 20 and 21:
Page 22 and 23:
Page 24 and 25:
Page 26 and 27:
10Network Communication Architectur
Page 28 and 29:
12Protocols GuideTCP/IP Protocolspo
Page 30 and 31:
14Protocols GuideTCP/IP - Applicati
Page 32 and 33:
Page 34 and 35:
Page 36 and 37:
Page 38 and 39:
Page 40 and 41:
Page 42 and 43:
Page 44 and 45:
Page 46 and 47:
Page 48 and 49:
Page 50 and 51:
Page 52 and 53:
Page 54 and 55:
Page 56 and 57:
Page 58 and 59:
Page 60 and 61:
Page 62 and 63:
Page 64 and 65:
Page 66 and 67:
Page 68 and 69:
52Protocols GuideTCP/IP - Session L
Page 70 and 71:
54Protocols GuideTCP/IP - Transport
Page 72 and 73:
Page 74 and 75:
Page 76 and 77:
Page 78 and 79:
Page 80 and 81:
64Protocols GuideTCP/IP - Network L
Page 82 and 83:
Page 84 and 85:
Page 86 and 87:
Page 88 and 89:
Page 90 and 91:
Page 92 and 93:
Page 94 and 95:
Page 96 and 97:
Page 98 and 99:
Page 100 and 101:
Page 102 and 103:
Page 104 and 105:
Page 106 and 107: 90Protocols GuideTCP/IP - Network L
Page 114 and 115: 98Protocols GuideTCP/IP - Data Link
Page 116 and 117: 100Protocols GuideTCP/IP - Data Lin
Page 118 and 119: 102Protocols GuideSecurity and VPNP
Page 120 and 121: 104Protocols GuideSecurity and VPN
Page 136 and 137: 120Protocols GuideVoice Over IP(VOI
Page 166 and 167: 150Protocols GuideWANOtherxDSL: Dig
Page 168 and 169: 152Protocols GuideWAN - ATM Protoco
Page 186 and 187: 170Protocols GuideWAN - Broadband A
Page 194 and 195: 178Protocols GuideWAN - PPP Protoco
Page 204 and 205: 188Protocols GuideWAN - Other WAN P
Page 206 and 207:
190Protocols GuideWAN - Other WAN P
Page 208 and 209:
Page 210 and 211:
Page 212 and 213:
196Protocols GuideLAN - Ethernet Pr
Page 214 and 215:
Page 216 and 217:
Page 218 and 219:
Page 220 and 221:
204Protocols GuideLAN - Virtual LAN
Page 222 and 223:
Page 224 and 225:
Page 226 and 227:
210Protocols GuideLAN - Wilress LAN
Page 228 and 229:
Page 230 and 231:
Page 232 and 233:
216Protocols GuideLAN - Other Proto
Page 234 and 235:
Page 236 and 237:
Page 238 and 239:
222Protocols GuideMAN ProtocolsProt
Page 240 and 241:
224Protocols GuideMAN Protocols(0).
Page 242 and 243:
226Protocols GuideStorage Area Netw
Page 244 and 245:
228Protocols GuideSAN ProtocolsProt
Page 246 and 247:
230Protocols GuideSAN ProtocolsThe
Page 248 and 249:
232Protocols GuideSAN Protocols•
Page 250 and 251:
234Protocols GuideSAN ProtocolsSpon
Page 252 and 253:
Page 254 and 255:
Page 256 and 257:
240Protocols GuideISO Protocols in
Page 258 and 259:
242Protocols GuideISO Protocols - A
Page 260 and 261:
Page 262 and 263:
Page 264 and 265:
Page 266 and 267:
Page 268 and 269:
Page 270 and 271:
Page 272 and 273:
Page 274 and 275:
Page 276 and 277:
Page 278 and 279:
262Protocols GuideISO Protocols - N
Page 280 and 281:
Page 282 and 283:
Page 284 and 285:
268Protocols GuideCisco ProtocolsPr
Page 286 and 287:
Page 288 and 289:
Page 290 and 291:
Page 292 and 293:
Page 294 and 295:
278Protocols GuideCisco Protocolsti
Page 296 and 297:
280Protocols GuideNovell NetWare an
Page 298 and 299:
Page 300 and 301:
Page 302 and 303:
Page 304 and 305:
288Protocols GuideIBM ProtocolsSNAT
Page 306 and 307:
290Protocols GuideIBM ProtocolsProt
Page 308 and 309:
292Protocols GuideIBM ProtocolsSNA
Page 310 and 311:
Page 312 and 313:
Page 314 and 315:
Page 316 and 317:
300Protocols GuideAppleTalk: Apple
Page 318 and 319:
302Protocols GuideDECnet and Protoc
Page 320 and 321:
304Protocols GuideSS7 / C7 Protocol
Page 322 and 323:
Page 324 and 325:
Page 326 and 327:
Page 328 and 329:
Page 330 and 331:
Page 332 and 333:
Page 334 and 335:
318Protocols GuideOther Protocols
Page 336 and 337:
320Protocols GuideOther ProtocolsPr
Page 338 and 339:
322Protocols GuideOther ProtocolsPr
Page 340 and 341:
324Network Protocols Dictionary: Fr
Page 342 and 343:
Page 344 and 345:
Page 346 and 347:
Page 348 and 349:
Page 350 and 351:
Page 352 and 353:
Page 354 and 355:
Page 356 and 357:
Page 358 and 359:
342Network Communication Protocols
show all

network protocols handbook.pdf

Create successful ePaper yourself

Delete template?

Save as template?