OTN±ê×¼¼ò½éV1.0
¹«¿ª¡ø£¨±£ÃÜÆÚ£©
G.709±ê×¼¹æ¶¨OTUkµÄFEC²ÉÓÃG.975±ê×¼Öж¨ÒåµÄFEC¸ñʽ¡£¸ù¾ÝG.975Öж¨ÒåµÄFEC¸ñʽ£¬FEC²ÉÓõÄË㷨ΪReed-Solomon RS(255,239)±àÂ룬¼ò³ÆRS£¨255£¬239£©»òÕßRS¡£RS(255,239)ΪһÖַǶþ½øÖƱàÂ루±àÂëËã·¨ÊÇÒÔ×Ö½Ú·ûºÅΪµ¥Î»½øÐеģ©£¬ÊôÓÚϵͳÏßÐÔÑ»·¿é±àÂëÀà¡£¹ËÃû˼Ò壬RS(255,239)¾ÍÊÇ˵¶ÔÓÚ239×Ö½ÚµÄÔʼÊý¾ÝÐèÒªÔö¼Ó16×Ö½ÚµÄУÑéÐÅÏ¢£¬×îºóÐγÉ239£«16£½255×Ö½ÚµÄÐÅÏ¢£¬ÆäÖÐ239ΪÔʼÊý¾ÝµÄ³¤¶È£¬255ΪÔʼÊý¾Ý¾¹ý±àÂë´¦ÀíºóµÄ³¤¶È£¬µ¥Î»¶¼ÊÇ×Ö½Ú¡£RS±àÂë×î¶àÔÊÐíͬʱ¾ÀÕý8¸ö×ֽڵĴíÎóÐÅÏ¢£¬Í¬Ê±×î¶àÄܹ»¼ì²âµ½16¸ö×ֽڵĴíÎó¡£Ò²¾ÍÊÇ˵£¬¶ÔÓÚ³¬¹ý8¸ö×Ö½Úµ«²»µ½16¸ö×ֽڵĴíÎ󣬽âÂëËã·¨Äܹ»¼ì²â³öʵ¼Ê´íÎóµÄ×Ö½ÚÊý£¬µ«ÎÞ·¨¾ÀÕý¹ýÀ´¡£ÓÉÓÚÈßÓàÐÅÏ¢Ö»ÓÐ16¸ö×Ö½Ú£¬ËùÒÔËã·¨×î¶àÖ»Äܼì²âµ½16¸ö×ֽڵĴíÎó¡£
ÔÚ½øÐÐFEC±àÂëʱ£¬Ã¿ÐÐOTUkÖ¡±»·ÖΪ16¸ö×ÓÐУ¨SubRow£©£¬Ã¿ÐÐ255¸ö×Ö½Ú£¬Õâ16¸ö×ÓÐÐÊÇÒÔ×Ö½Ú¼ä²åµÄ·½Ê½Ðγɣ¬Èçͼ6Ëùʾ¡£
Information bytes12 2 3 4 9 0 Parity check bytes2 5 5 FEC sub-row #16Information bytes1239Information bytes1239240240Parity check bytesFEC sub-row #2255FEC sub-row #1255Parity check bytes3 8 2 4 3 8 2 5 3 ... 8 2 6 3 8 4 0 4 0 8 0 G.709/Y.1331_FA.1Parity check bytesInformation bytes1 2 ... 1 6 OTU row ͼ6 OTUk FECµÄ×ÓÐнṹ
ÔÚ½øÐÐ×Ö½Ú¼ä²åʱ£¬Êý¾ÝºÍУÑéÐÅÏ¢ÊÇ·Ö¿ª½øÐÐ×Ö½Ú¼ä²åµÄ¡£Ò²¾ÍÊÇ˵£¬16¸ö×ÓÐÐÖÐÿÐж¼·Ö³É239×Ö½ÚµÄÊý¾ÝºÍ16¸ö×Ö½ÚµÄУÑéÐÅÏ¢£¬16¸ö×ÓÐÐÖеÄÊý¾Ý½øÐÐ×Ö½Ú¼ä²å£¬¹²µÃµ½16¡Á239£½3824×Ö½ÚµÄÊý¾Ý£¬È»ºóÊÇ16¸ö×ÓÐÐÖеÄУÑéÐÅÏ¢½øÐÐ×Ö½Ú¼ä²å£¬¹²µÃµ½16¡Á16£½256×ֽڵļìÑéÐÅÏ¢£¬×éºÏµ½Ò»Æð¾Í¹¹³ÉÁËOTUkÖ¡µÄÒ»ÐС£
Ò²¾ÍÊÇ˵£¬ÔÚOTUkÖ¡µÄÿÐÐÖУ¬µÚ1ÁÐΪ×ÓÐÐ1µÄµÚ1¸ö×Ö½Ú£¬µÚ2ÁÐΪ×ÓÐÐ2µÄµÚ1¸ö×Ö½Ú£¬...£¬µÚ16ÁÐΪ×ÓÐÐ16µÄµÚ1¸ö×Ö½Ú£¬È»ºóµÚ17ÁÐΪ×ÓÐÐ1µÄµÚ2¸ö×Ö½Ú£¬µÚ18ÁÐΪ×ÓÐÐ2µÄµÚ2¸ö×Ö½Ú£¬...£¬Ö±µ½µÚ3824ÁÐΪ×ÓÐÐ16µÄµÚ239×Ö½Ú¡£´ÓµÚ3825×Ö½Ú¿ªÊ¼ÊǽøÐÐÁË×Ö½Ú¼ä²åµÄУÑéÐÅÏ¢¡£
¾¹ýÒÔÉÏ´¦Àíºó£¬Ã¿ÐÐÓÉÇ°ÃæµÄ3824×Ö½ÚÊý¾ÝºÍºóÃæµÄ256×Ö½ÚµÄУÑéÐÅÏ¢£¬ÕâÒ²ÕýÊÇOTUkÖ¡½á¹û¶¨ÒåµÄÓÉÀ´¡£
¸ù¾ÝFECµÄÔÀíÒ²¿ÉÒÔÀí½âΪºÎOTUkÖ¡Ò»Ð㤶ÈΪ4080×Ö½Ú¡£ÓÉÓÚOTUkµÄFECÂëÊÇ°´ÕÕ£¨255£¬239£©µÄ·½Ê½ÊµÏֵģ¬ËùÒÔOTUkÖ¡µÄÿÐбØÐëÊÇ255×Ö½ÚµÄÕûÊý±¶¡£OTUkÑ¡ÔñÁËÒ»ÐÐÓÉ16¸öFECÏî×é³É£¬Ã¿¸öFECÏîΪ255×Ö½Ú£¬ÆäÖÐУÑéÐÅϢΪ16×Ö½Ú£¬Êý¾ÝÐÅϢΪ239×Ö½Ú£¬Ã¿¸öOTUkÖ¡ÔÙÓÉ4ÐÐ×é³É£¬ÕâÑùÒ»¸öOTUkÖ¡Ðеij¤¶ÈΪ255*16£½4080×Ö½Ú¡£ÆäÖмìÑéÐÅϢΪ16*16£½256×Ö½Ú£¬Êý¾ÝÐÅϢΪ239*16=3824×Ö½Ú£¬Ö¡µÄʵ¼Ê³¤¶ÈÊÇÒÔÉÏÊý¾ÝÔÙ³ËÒÔ4¡£±¾ÎÄÖеÄËùÓÐÐÅÏ¢¹éÖÐÐËͨѶ¹É·ÝÓÐÏÞ¹«Ë¾ËùÓУ¬Î´¾ÔÊÐí£¬²»µÃÍâ´« µÚ 11 / 41 Ò³
OTN±ê×¼¼ò½éV1.0
¹«¿ª¡ø£¨±£ÃÜÆÚ£©
ÔÚOTUkµÄ3824*4×Ö½ÚÊý¾ÝÐÅÏ¢ÖУ¬½«Ç°16ÁÐ×÷Ϊ¿ªÏú£¨°üÀ¨OTUk£¬ODUkºÍOPUkµÄ¿ªÏú£©£¬ºóÃæµÄËùÓÐÐÅÏ¢£¨3824-16£©*4¾ÍÊÇOPUkµÄ¾»ºÉ£¬Ò²¾ÍÊÇÕæÕýµÄÊý¾ÝÐÅÏ¢Payload¡£
5.1.3 OTUkÖ¡µÄ¼ÓÈÅ
OTUk֡ΪÁËÔÚÏß·ÉÏ´«Ê䣬±ØÐë±£Ö¤ÂëÐÍÖÐ1ºÍ0µÄ±ÈÀý»ù±¾Ï൱£¬±ÜÃâ³öÏÖ³¤Á¬0»òÕß³¤Á¬1µÄÇé¿ö£¬ÕâÑù²ÅÄܱ£Ö¤½ÓÊÕÉ豸Äܹ»´ÓÒµÎñÖÐÌáÈ¡³öʱÖÓ¡£Îª´Ë£¬OTUkÖ¡±ØÐë¾¹ý¼ÓÈźó²ÅÄÜÔÚÏß·ÉÏ´«Êä¡£OTUk֡ʹÓöàÏîʽ½øÐмÓÈÅ£¬¶àÏîʽΪ1 + x + x + x + x£¬Èçͼ7Ëùʾ¡£
Data in3
12
16
DQOTUkclockSDQSDQSDQSDQSDQSDQSDQSDQSDQSDQSDQSDQSDQSDQSDQSScrambleddata outOTUk MSB of MFAS byteG.709/Y.1331_F11-3
ͼ7 OTUkÖ¡µÄ¼ÓÈÅËã·¨
¼ÓÈÅ´ÓOTUkÖ¡µÄÖ¡¶¨Î»×îºóÒ»¸ö×Ö½Ú½áÊøʱ¿ªÊ¼£¬Ò²¾ÍÊÇ˵µÚÒ»¸ö±»¼ÓÈŵÄλΪ16
MFAS×Ö½ÚµÄMSB¡£Ã¿´ÎÓöµ½MFASµÄMSBʱ£¬¼ÓÈŶàÏîʽ»á¸´Î»³ÉĬÈÏÖµ0xffff£¬ÒÔºó´ËλºóÃæµÄËùÓÐλ¿ªÊ¼±»¼ÓÈÅ¡£xµÄÊä³öºÍÒµÎñÊý¾Ý루µÚÒ»¸öÒµÎñÊý¾ÝλΪMFASµÄMSB£¬ÒÔºóÒÀ´ÎÊÇOTUkÖ¡ÖеÄÆäËû룩×÷Ä£2¼Óºó¼´µÃµ½¼ÓÈźóµÄ½á¹û¡£ÓÉÓÚ¼ÓÈÅÊÇ´ÓMFASµÄMSB¿ªÊ¼µÄ£¬ËùÒÔÖ¡×ʼµÄ6¸ö×Ö½ÚµÄÖ¡¶¨Î»ÐÅϢûÓб»¼ÓÈÅ¡£ ¼ÓÈÅÊÇÕë¶ÔOTUkÖ¡½øÐеģ¬ÓÉÓÚFECΪOTUkÖ¡ÖеÄÄÚÈÝ£¬ËùÒÔ¼ÓÈÅÒ²ÊÇÔÚFEC±àÂëºó½øÐеġ£ ×¢Ò⣬¸ù¾ÝG.707±ê×¼£¬SDH¼ÓÈÅʹÓõĶàÏîʽΪ1 ? X6 ? X7£¬ºÍOTUkµÄ¼ÓÈŶàÏîʽ²»Ò»Ñù¡£ OTUkÐèÒªÔÚ±àÂëºó½øÐмÓÈÅ£¬¾¹ý´«ÊäºóÒ²±ØÐë½âÈźó²Å½øÐнâÂë²Ù×÷¡£½âÈźͼÓÈŵÄËã·¨ÍêÈ«Ò»Ñù£¬¶Ô¼ÓÈŵÄÐźÅÔÙÖ´ÐÐÒ»´Î¼ÓÈŲÙ×÷¼´Ï൱ÓÚ¶ÔÐźŽøÐÐÁ˽âÈÅ¡£
5.2 ODUkµÄÖ¡½á¹¹
ODUkµÄÖ¡½á¹¹ÓÉÁ½²¿·Ö×é³É£¬·Ö±ðΪODUk¿ªÏú£¨ODUk Overhead£©ºÍOPUkÖ¡£¬Èçͼ8Ëùʾ¡£OPUkÖ¡½«ÔÚ4.5½ÚÖнéÉÜ¡£ÕâÀï½éÉÜODUkµÄ¿ªÏú¡£ Column #1114153824Row #234Area reserved for FA and OTUk overhead.ODUk overheadareaOPUk area(4 ? 3810 bytes)G.709/Y.1331_F12-1ͼ8 ODUkµÄÖ¡½á¹¹
ODUkµÄ¿ªÏúÕ¼ÓÃOTUkÖ¡µÚ2£¬3£¬4ÐеÄÇ°14ÁС£µÚÒ»ÐеÄÇ°14Áб»OTUk¿ªÏúÕ¼
¿ª
Ïú
µÄ
Ïê
ϸ
½á
¹¹
Èç
ͼ
9
Ëù
ʾ
¡£
¾Ý¡£ ODUk
±¾ÎÄÖеÄËùÓÐÐÅÏ¢¹éÖÐÐËͨѶ¹É·ÝÓÐÏÞ¹«Ë¾ËùÓУ¬Î´¾ÔÊÐí£¬²»µÃÍâ´« µÚ 12 / 41 Ò³
OTN±ê×¼¼ò½éV1.0
ColumnRow1114151617¹«¿ª¡ø£¨±£ÃÜÆÚ£©
3824BIP8 Parity Block234OPUkoverheadOPUk payload(4 ? 3808 bytes)Column #112345678910111213141516Frame alignment overheadRESTCM3GCC1GCC2TCMACTTCM2APS/PCCTCM6TCM1TCM5OTUk overheadTCM4PMRESFTFLEXPOPUkoverheadRow #234ACT Activation/deactivation control channelAPS Automatic Protection Switching coordination channelBDI Backward Defect IndicationBEI Backward Error IndicationBIAE Backward Incoming Alignment ErrorBIP8 Bit Interleaved Parity ?level 8DAPI Destination Access Point IdentifierEXP ExperimentalFTFL Fault Type & Fault Location reporting channelGCC General Communication ChannelPCC Protection Communication Control channelPM Path MonitoringPSI Payload Structure IdentifierPT Payload TypeRES Reserved for future international standardizationSAPI Source Access Point IdentifierSTAT StatusTCM Tandem Connection MonitoringTTI Trail Trace IdentifierPM and TCMi (i = 1..6)1TTI2BIP-8312012345678OPUk OH1516PMSAPI1516DAPI3132Operatorspecific63BDI34Mapping &Concat.specificBEI1234STATPSI678PT01Mapping &Concat.specific255G.709/Y.1331_F15-3TCMi5BDIBEI/BIAESTAT ͼ9 ODUkµÄ¿ªÏú½á¹¹
ODUk¿ªÏúÖ÷ÒªÓÉÈý²¿·Ö×é³É£¬·Ö±ðΪPM(Path Monitering)ºÍTCM(Tandem Connection
Monitoring)ºÍÆäËû¿ªÏú¡£ÆäÖÐPMÖ»ÓÐÒ»×鿪Ïú£¬¶øTCMÓÐ6×鿪Ïú£¬·Ö±ðΪTMC1-6¡£PMºÍTCM´ú±íODUkÖ¡Öв»Í¬µÄ¼à²âµã¡£ODUk¸÷¿ªÏúµÄÏêϸλÖÃÈçͼ10Ëùʾ¡£
Column #112345678910111213141516Frame alignment overheadRESTCM3GCC1GCC2TCMACTTCM2APS/PCCTCM6TCM1TCM5OTUk overheadTCM4PMRESG.709/Y.1331_F15-12Row #234FTFLEXPOPUkoverhead±¾ÎÄÖеÄËùÓÐÐÅÏ¢¹éÖÐÐËͨѶ¹É·ÝÓÐÏÞ¹«Ë¾ËùÓУ¬Î´¾ÔÊÐí£¬²»µÃÍâ´« µÚ 13 / 41 Ò³
OTN±ê×¼¼ò½éV1.0
ͼ10 DDUk¿ªÏú¸÷×ֶεÄλÖÃ
ÏÂÃæ·Ö±ð½éÉÜ¡£
5.2.1 ODUkµÄPM¿ªÏú
ODUk PM¿ªÏúµÄ½á¹¹¶¨ÒåÈçͼ11Ëùʾ¡£
PM1TTI2BIP-83¹«¿ª¡ø£¨±£ÃÜÆÚ£©
0SAPI1516DAPI313212345BDI67STAT8BEIG.709/Y.1331_F15-13Operatorspecific63 ͼ11 ODUk PM¿ªÏúµÄ½á¹¹ ODUk PM¿ªÏúµÄλÖÃλÓÚµÚÈýÐУ¬×Ö½Ú£¨3£¬10£©ÖÁ×Ö½Ú£¨3£¬12£©£¬¹²3¸ö×Ö½Ú¡£ODUkµÄPM¿ªÏú½á¹¹ºÍOTUk SM¿ªÏú²î²»¶à£¬Î¨Ò»²»Í¬µÄÊÇSM-IAE¼ÓSM-RESµÄλÖñ»PM-STATËù´úÌæ¡£ODUk PM¿ªÏúÓÉÏÂÃ沿·Ö×é³É£º ? ? ? ? ?
trail trace identifier (TTI); bit interleaved parity (BIP-8); backward defect indication (BDI); backward error indication (BEI); status bits indicating the presence of a maintenance signal (STAT). PM-TTI£¬È«³ÆΪODUk PM trail trace identifier (TTI)£¬³¤¶ÈΪһ¸ö×Ö½Ú£¬Î»ÖÃΪ×Ö½Ú£¨3£¬10£©¡£´Ë×Ö¶ÎÓÃÓÚ´«ËÍ·¾¶¼à²â(Path Monitoring)ÖеÄTTIÐÅÏ¢£¬ÓÉÁ¬Ðø64Ö¡ÖеĴ˿ªÏú×é³É64×Ö½ÚµÄÐÅÏ¢£¬¶¨ÒåͬSM-TTIÍêÈ«Ò»Ö¡£´Ë64×Ö½ÚTTIÐÅÏ¢ÔÚOTUk¸´Ö¡ÖеĶÔÆ뷽ʽҲºÍSM-TTIÍêÈ«Ò»Ñù£¬µÚÒ»×Ö½Ú·Ö±ð¶ÔÓ¦ÓÚ¸´Ö¡0£¬0x40,0x80,0xc0¡£
PM-BIP-8£¬È«³ÆΪODUk PM error detection code (BIP-8)£¬³¤¶ÈΪһ¸ö×Ö½Ú£¬Î»ÖÃΪ×Ö½Ú£¨3£¬11£©¡£´Ë¿ªÏúΪBIP-8УÑéÐÅÏ¢£¬½á¹¹ºÍ¶¨Òå»ù±¾Í¬SM-BIP-8£¬µ«ÓÃÓÚ·¾¶¼à²âÖС£PM-BIP8µÄ¼ÆË㷶ΧΪÕû¸öOPUkÖ¡£¨µÚ15Áе½µÚ3824ÁУ¬OPUkÖ¡µÄ½á¹¹¼û5.3£©£¬ºÍSM-BIP8Ò»Ñù£¬µÚiÖ¡µÄBIP-8УÑé½á¹û·Åµ½µÚi£«2Ö¡µÄPM-BIP8¿ªÏúλÖÃÉÏ£¬Èçͼ12Ëùʾ¡£
±¾ÎÄÖеÄËùÓÐÐÅÏ¢¹éÖÐÐËͨѶ¹É·ÝÓÐÏÞ¹«Ë¾ËùÓУ¬Î´¾ÔÊÐí£¬²»µÃÍâ´« µÚ 14 / 41 Ò³