C[TlbgFTech Basics^Keywordi1/2 y[Wj
LANSƂ͂AItBXł͗Llbg[ŃuC[Tlbgv܂܂pĂB̎ނ⑬xA쌴́H 40Nȏ̗jUԂB
@uC[TlbgiEthernetjv́AXeroxЂPalo Alto Research CenteriPARCjRobert M. Metcalfemɂ1970NɊJꂽlbg[NVXeBEthernetƂ̂́A19IɁAdg`di`jzIȕƍlĂuEtheriG[ejvƁuNetworkilbg[Njv킹łB
@ݍLyĂC[TlbǵA1983NɁuIEEE 802.3 CSMA/CDvƂĐ肳ꂽ̂ƂȂĂiIEEE 802.3́AC[Tlbg̋Ki𐧒肷IEEE̍ƕjB̌AʐMx10Mbit/s100Mbit/sA1Gbit/sA10Gbit/sAccƍ̂AcCXgyAP[ut@Co[Ȃǂ`}̂ɎgpKiȂǂAW𑱂ĂB
C[Tlbg̃g|W[FoX^ƃX^[^
@J̃C[Tlbg̓oX^̃A[LeN`̗pĂB1{̃oXiP[ujɕ̃m[hiRs[^jڑĂ`̃lbg[NłB
oX^ƃX^[^̃lbg[Ng|W[ŏ̃C[Tlbg̓oX^łA݂ł̓nuiXCb`j𒆐SƂX^[^嗬łBoX^ł́AMłm[h͂ǂꂩ1䂾ŁA2ȏオɑMJnƃf[^Փ˂ĎsĂ܂BXCb`g݂̃C[Tlbgł́AXCb`ƃm[h11ŐڑĂāÃm[hɑMsĂՓ˂邱Ƃ͂ȂB
@肳ꂽ10BASE5ƂKił́AŒ500m̓P[u5{܂s[^[ipjŘAāAő咷2.5km܂ł̃lbg[N\z邱ƂłBlbg[NɐڑꂽRs[^́AqCSMA/CDƂANZXgăf[^𑗐MB
@P[up͐ݒu舵eՂł͂Ȃ߁ALyɂ͎ȂB̌cCXgyAP[ut@Co[P[uƁunuvuXCb`vgX^[^̃lbg[NJA}ɕyiB
C[Tlbg̃t[\
@C[Tlbgł́Aem[hMpPbg̍\͎̂悤ɂȂĂB
C[Tlbg̃t[\C[Tlbgł1pPbg46`1500bytes̃f[^𑗐MłiMf[^46bytes̏ꍇ́A炩̃_~[f[^߂đMjB
EAhXFM\6bytesMACAhX
EMAhXFMRs[^MACAhX
E^CvFvgR̃^CvA̓f[^
EVLAN^OFVLANizlbg[Nj̃^O\l
EFCSFG[`FbNpCRCR[h
ELAGNXeVFMKrbgC[Tlbgi1000BASE-xjɂāAŏt[TCY512bytesɊg傷邽߂̃_~[f[^
@xɑMłf[^͍ŏ46bytesAő1500bytesłBȂŏTCY1byteł͂Ȃ46bytesƂƁACSMA/CDɂՓˌomɍs߂B
C[Tlbg̃ANZXFCSMA/CD
@̃C[Tlbgł́A1{̓P[uɑ̃Rs[^ڑĂ邪A𒆉WIɊǗ@\͗pӂĂȂBɊeRs[^́uCSMA/CDiCarrier Sense Multiple Access with Collision DetectionjvƂANZXgāAM̊mۂƃf[^̑MȂǂsĂB
@́AP[uĂ邩ǂāAĂΑMn߂邪ArŏՓ˂N炵炭҂ĂđMAƂ@łBڍׂ͎̒ʂB
- oXgpǂ܂mFiCarrier SenseAoXɓdCMĂ邩ǂŔfj
- ĂΊeRs[^ꂼꎩRɑMn߂iMultiple Accessj
- M̃P[u̓dCMĎAMBMɑ̃Rs[^Mn߂ƓdCMՓ˂AP[u̐MBo
- MrŏՓ˂oiCollision DetectionjA炭҂ĂđMiő16sj
@M̓`鑬x͗LȂ̂ŁiP[uȂ̖6jA2̃Rs[^P[űoĂ瑗Mn߂ƂĂArŕKMՓ˂邱ƂɂȂB̏ꍇ݂͂Ƀ_Ȏԑ҂ĂđMB
@M͏ɃP[u̐Mj^ĂAAhXɂȂĂpPbgĂA荞ŏʃvgR֓nAƂB
@̂悤ɔɃVvȎdg݂ł邪ApႢԁiႦΕσpPbg64bytesȂAނ3ȉjȂΏՓ˂̔pxȂAIɗpłƂĂB
@P[uɐM𑗐Mł̂͂1䂾łA2䂪MƎMsAƂƂ͂łȂBMꍇ́AKԍŕėpKvB̂悤ȒʐMdƂB
@ɑāÃ݂nuiXCb`jƃcCXgyAP[u^t@Co[gʐMł́AXCb`ƃRs[^Ԃ̓|CgEc[E|CgSdʐMƂȂĂB
RWhC
@CSMA/CDLɋ@\邽߂ɂ́AՓ˂̔mɌoKvB̂߂Ɍ߂Ă̂A`xƃP[u̍ő咷ApPbg̍ŏTCY̊WłB10BASE5̃P[u͍ő2.5kmłÄ[瑗MMΑ܂ōsĂՓ˂Ė߂Ă܂ł̎ԂƓdqHł̒xȂǂ킹ƁA50ʕbxi1ʕb1001bjBŏpPbgTCYƂ64bytesi512bitj߂ꂽB菬ƁAʒuWɂĂ͏Փ˂Oɑɓ͂Ă܂ƂɂȂAՓ˂ołȂȂBP[ûǂŏՓ˂ꍇAKSm[hɂ܂œ`悤ɁAŏTCY߂ĂB
@̏Փ˂`͈͂uRWhCvƂB
MpPbg̏Փ˂ƃRWhCCopyright© Digital Advantage Corp. All Rights Reserved.
ڂ̃e[}
ITmedia̓ACeBfBAЂ̓o^WłB