【正文】
.5 101 0101 1010 .6 110 1001 0110 .7 111 0111 1000 Data Label Data Bit Current RD() Current RD(+) HGF fghi fghi 3B4B 特定組編碼 千兆以太網(wǎng) 8B10B 碼特性: ? High transition density of 3 8 transitions per 10 bit code group ? DC balance 。 參 數(shù) 10Mbps 100Mbps 1000Mbps 隙時(shí) (Slot time) ?s 幀間隔 (Inter Frame Gap) ?s 嘗試次數(shù) (Attempt Limit) 16 退避次數(shù) (Back off Limit) 10 阻塞信號(hào) (Jam Size ) 32bits Max Frame Size 1518 bytes Min Frame Size 64 bytes 地址長度 (Address Size ) 6 bytes 512 bit times ?s 16 10 32bits 1518bytes 64bytes 4096 bit times ?s 16 10 32bits 1518bytes 64bytes Pre SFD DA SA L / T FCS Ext 88 08. MSO 01 00 LSO 1 Byte 1 Byte MAC 控制幀格式 MAV控制 操作碼 操作碼參數(shù) 60 octets 2 bytes 00010001 00000001 Pre SFD DA SA L / T FCS Ext 88 08. MSO 01 00 LSO 1 Byte 1 Byte MAC 控制 ( pause ) 幀格式 MAV控制操作碼 0001 pause time 60 字節(jié) 2 bytes 00010001 00010000 LSB MSB Pre SFD DA SA L / T Data PAD FCS Ext Tag type Tag Control info. MSO 01 00 LSO 0 7 LS b MS b 8100 2 Byte 2 Byte 10000001 00000000 ( 33024 ) VLAN Tagged MAC 幀格式 42 1496 Octets IEEE Pre SFD DA SA L / T Data PAD FCS Ext Tag type Tag Control info. 2 Byte 2 Byte User Priority CFI VLAN identifier b2 b0 b11 b0 VLAN Tagged MAC 控制信息字段 ( ) CFI : Canonical Format Indicator 用于指示在 MAC Client 數(shù)據(jù)字段內(nèi)有無 路由信息字段 (RIF)。y 1997 全雙工 (交換機(jī)端口 網(wǎng)站 ) ? IEEE 1998 ? IEEE 1998 VLAN tagging 介質(zhì)訪問控制 (MAC) IEEE ? IEEE Std. 1998 “ Information Technology Telemunications and information exchange between systems Local and metropolitan area work Specific requirements Part 3 : Carrie Sense Multiple Access with Collision Detection ( CSMA / CD ) access method and physical layer specifications ” ISO / IEC 8802 3 : 1996 ? IEEE draft Std. ab 1000 BASE T UTP 5 ? IEEE Std. 1998 Virtual Bridged LAN tagging on Networks ? IEEE Std. : Link aggregation Pre SFD DA SA L / T Data PAD FCS Ext 基本 MAC 幀格式和傳輸順序 傳輸順序:自左至右,比特流 幀開始界符 1010