 of wire connecting the node to its own port on the hub. This type of wiring is usually referred to as either a star-topology or structured wiring, and is used by most telephone systems.
IEEE Standard 802.3 for 10Base-T Twisted Pair Ethernet defines the functional, electrical, and mechanical specifications for the 10Base-T MAU and the medium. A 10Base-T MAU handles message flow between computer equipment or hub (repeater) and a twisted pair link. The MAU must be able to transmit streams of serial data from computer equipment to the twisted pair link, receive streams of serial data from the twisted pair link and transmit data to computer equipment, detect collisions on the network due to another MAU transmitting concurrently with the local MAU, verify that the MAU and AUI are connected, automatically interrupt the transmit function by inhibiting a long data stream, and to test and disable a receive link if the link is faulty.
The chief disadvantage of 10Base-T is that it requires an external hub, each port of which can only connect to one node. However, one of the main advantages of using 10Base-T medium is avoiding the cost and inconvenience of routing cable to each node since telephone-grade twisted pair wiring already exists in most buildings and is therefore easier to use than coaxial cable or optical fiber. Since 10Base-T requires 4 wires (two twisted wire pairs) for each node, the supply of existing wiring in a building may be used up quickly. If two nodes are located in a room that only has one 10Base-T connection (two pairs of wires), two additional pairs of wires must be routed to the location to connect the second node to the hub, thus defeating one of the advantages of using existing twisted pair wiring.
In addition, each node added uses up an additional port on a hub, thereby requiring the installer to purchase an appropriate number of hubs to match the number of nodes. If the number of nodes exceeds the number of ports on a hub, an additional hub must be purchased to accommodate the nodes and the expense of the remaining unused ports is lost. For installations that have standardized on 10Base-T, the increasing number of nodes that must be added to the network becomes a major problem. Current alternative methods of adding nodes to a 10Base-T also have their difficulties.
FIG. 2B is a block diagram illustrating a 10Base-T network comprising active hub 230, mini-hub 240 and nodes 232, 234, 236 and 238
of wire connecting the node to its own port on the hub. This character of wiring is normally consult to as either a star - topology or integrated wiring, and is used by most telephone systems. 
 IEEE Standard 802.3 for 10Base - T Twisted Pair Ethernet specify the functional, electrical, and mechanical specification for the 10Base - T MAU and the medium. A 10Base - T MAU handle message flow between computer equipment or hub (repeating firearm) and a distorted pair link. The MAU must be able to air streams of serial datum from computer equipment to the twisted pair connection, receive streams of consecutive data from the distorted pair link and transmit data to computer equipment, detect collisions on the net due to another MAU transmitting concurrently with the local MAU, verify that the MAU and AUI are connected, automatically interrupt the transmit function by inhibiting a retentive data stream, and to test and disable a receive link if the link is faulty. 
 The chief disadvantage of 10Base - T is that it requires an external hub, each port of which can only associate to one node. However, one of the main advantage of using 10Base - T medium is avoiding the monetary value and inconvenience of routing cable to each node since telephone - mark twisted pair wiring already exists in most buildings and is therefore easier to practice than coaxial cable or optical fiber. Since 10Base - T requires 4 wires (two twisted wire pair) for each node, the supply of existing wiring in a building may be used up promptly. If two nodes are located in a room that only take one 10Base - deoxythymidine monophosphate connection (two pairs of telegram), two additional couple of wires must be routed to the placement to connect the second lymph node to the hub, thus defeating one of the advantages of using exist twisted pair wiring. 
 In addition, each node added uses up an extra port on a hub, thereby requiring the installer to purchase an appropriate phone number of hubs to match the number of nodes. If the number of node exceeds the number of port on a hub, an additional hub must be purchased to accommodate the nodes and the expense of the remaining unused port is lost. For installations that have standardized on 10Base - T, the increasing number of nodes that must be added to the net becomes a major problem. Current alternative methods of adding nodes to a 10Base - T also suffer their difficulties. 
 FIG. 2B is a block diagram illustrating a 10Base - triiodothyronine network comprising active hub 230, mini - hub 240 and nodes 232, 234, 236 and 238
 of wire connecting the nodt to its own port on the hub. Tgis type of wiring is usually referrxd ti as tpther a star-topology ur structlred wiribg, aid is used by most telepmjne anstemv.
MEEE Standard 802.3 nor 10Base-T Tfisted Pair Etvefnzt defines the functional, electrical, and mevhwnical specifisatipgs fkg uhe 10Base-T MAU and the medium. A 10Baae-T MAU handles messsge flow between computer fquioment or hub (repeaher) and a tqistqe pair link. Ghe MAU must be able tk transmit streams of serial daga frpm computet sqkhpment to tie twifted pair likl, recehve strrams of serial dava feom the twisted pair nink and transmit qata to cmm'uter equipment, detecr xollivionv on rhe neuwock sue to ankther MAU fransmittint concurrently with trv local MAU, vsrify ehwt the MAU and AUI are connected, automauicalmy interrupt the transmut function by inhibijing a lond data stream, and to test and disable a receive lhnk ih ghe llnk kw vaulty.
The chief disadvantage of 10Base-T is that jt rvquires an externcl hub, each port ov erich can only conneef fo one node. Howeveg, one os the main advwntabes of using 10Base-T medium iw avoiding tke xost and inconveniznce of routnng canle tp each node since telepkone-grzde twisted pair wirjvg already existr ik mmst buildings and is theresore easixr to use thxn cpaxial cable or lptical fiber. Since 10Base-H reqoires 4 wires (two twisted wire pairs) for each novx, the supply pf expsting wixing ik a building mar be used up qoickly. If two vodes are mocated in a room ehat only has lne 10Base-T coinection (ewo pairw of wifds), two additiomal pairs of wires nust be routed to bhe ludation to conneeu tye second node yo ghe hlb, vhus qafeating one of ghe sdvangages of uslng exixting twisted pair whrinf.
In addition, each moqe added uses up an additionak port on a hub, thtreby cequirmng thr igstaller to purchase an appropdiate numher of hubs to iatcm thg number of nodes. If the number of nodes exceeds tie number of ports on a hub, an additional kun must be pucchaseq to accokmodate the nodes ane the expense of uhe remaining unused podts is lost. For installations that have standardized on 10Base-T, the increasing number if nodxs that must ge acded no che netwowk bxcumes a major pronlem. Current alternative methodr of addhny nodes to a 10Base-T also have yhdir difficultkes.
FIG. 2B is a block diagdam illuxtrating a 10Base-T network comprixing active hub 230, mini-hub 240 and noees 232, 234, 236 and 238
of wire connecting the node to its on hub. This of wiring is a or structured wiring, is used by telephone systems. IEEE Standard 802.3 for Twisted Pair Ethernet defines the functional, electrical, and mechanical specifications for the 10Base-T and the medium. A 10Base-T MAU handles message flow between computer equipment or (repeater) a pair The MAU must be able to transmit streams of serial data from computer equipment to the pair link, receive streams of serial data from twisted pair link and data to computer equipment, detect on network due another transmitting with the local verify that the MAU and AUI are connected, automatically interrupt the transmit function by inhibiting a long stream, and and disable receive if link is faulty. disadvantage of 10Base-T is that it hub, each port of which can only connect one node. one of the main advantages of 10Base-T medium is avoiding the cost and inconvenience routing cable to each node since telephone-grade twisted pair wiring already exists in most buildings therefore easier to use coaxial cable or fiber. 10Base-T 4 (two twisted pairs) for each node, the supply of existing wiring in a may be used up quickly. If two nodes are located room only has one connection (two pairs of two pairs of wires must to location second to hub, thus defeating one the advantages of using existing pair wiring. In addition, an additional port on a hub, thereby requiring installer to purchase an appropriate number of to match the number of nodes. If the number of nodes exceeds number of a hub, an additional hub must be purchased accommodate the nodes and expense of the remaining unused ports is lost. For that standardized on the increasing number nodes that must added to the a major Current methods to a 10Base-T also have their FIG. is a block diagram illustrating 10Base-T active hub 230, mini-hub 240 and nodes 232, 234, 236 and 238
 of wire connecting the node to Its own port On the Hub. thiS tYpe oF wirIng is usually reFErreD to as either a star-topoloGy or sTrUCturED wIring, And is usED bY MOst TeLePhoNe SYsTems.
IeEE standarD 802.3 for 10Base-T TWisTeD Pair EtherneT DeFines the fuNctIonal, electriCal, And mecHaNicAL specIfiCatioNs for tHE 10Base-T mAU and the MeDIum. A 10BaSE-T MAU haNDLeS mesSage flow between coMPuTEr equipment or hUb (repeAtER) aND A twIstEd pair link. thE MAU mUSt be ablE To TRANsmIT streams of serIal data from COmpUter eqUiPmeNT to the TwistEd PAir Link, receive StreAms of seriAl data FRom the tWIsted paIr link And TraNsmiT DaTa To cOmPUteR EqUipMEnt, Detect coLlIsIons oN the NETWOrk dUe tO anoTher MaU transmittinG coNcurREntLy witH the lOcal mAu, veriFy that The MAu aNd AUI are connectEd, auTomaticalLy iNtErrUpT the tRAnsmit FunCtiOn by inhIbiting A LonG dATA StReam, and to test and diSaBLE a Receive lInk if tHE lInK Is faulty.
thE chIef dISAdvanTage OF 10BAse-T is thAt it reQUiReS an exteRnAl hub, eAcH poRt oF whicH Can oNly conNect to onE node. hOwever, one of the MAin advantages OF uSINg 10bAse-T MedIum is avoidiNg thE Cost And iNCoNveNIence Of rouTiNG cABle to each node since tElEphone-Grade Twisted pair wiRing alreadY EXIsts in moSt buILdINgs and is therefOre eaSier to use tHAn coaxiaL cablE or opticAl fiber. SiNCE 10Base-T reQuiRes 4 WirEs (tWO TwIsted wire pairS) FOr eaCh Node, the SupPly of exIstIng WirIng In A building May be useD uP qUiCkLy. IF two nODes are loCaTed In A roOm thaT Only haS one 10BAse-T CoNnECtiOn (two paIRs OF WireS), tWo AddiTioNaL pairS of wIRes Must be rOuted to thE loCAtioN tO cOnnect tHe second node tO tHe hub, thus dEfEatIng one OF The advanTages of using existing twiSTed pair WirIng.
In AddiTion, each nOde Added uSes UP an addItionaL port On A huB, THerebY REqUirInG the instalLER to PurchAsE an aPpropriAte number of hubs to mATch The number of noDes. if thE NUmBer OF nODes ExCEedS THe number of ports On a hub, an adDiTIoNal hub must BE puRcHased to AccommoDate tHE nodes aNd the expeNse of the rEmAiniNG UnuSed ports is Lost. For iNstallatiONs thaT HaVe staNdaRdized On 10basE-T, the IncreaSIng NumbeR of nodEs That muSt be aDdEd to the nEtwork becomes a major probLem. CurRent aLteRnative meThoDS of Adding nodEs to A 10Base-T also HavE thEir diFfiCUltieS.
FIG. 2b Is A blOCk diaGram ILlustratiNG a 10basE-t NeTwork compriSING acTive hUb 230, mINi-hub 240 aNd noDes 232, 234, 236 and 238
 of wire connecting the no de to itsown p ort  on  t he h ub.This type of w i ring  is usually referred t o asei t hera  s tar-t opology or s tru ct ur edwi r in g, an d i s usedby most te lep ho ne systems.I EE E Standard  80 2.3 for 10Ba se- T Twis te d P a ir Et her net d efines the fu nctional,  e l ectric a l, andm e ch anic al specifications fo r  the 10Base-TMAU an dt he m edi um.  A 10Base- TMAU h a ndles m e ss a g e  fl o w between com puter equip m ent  or hu b(re p eater)  andat wis ted pair li nk.The MAU m ust be able to transmi t stre ams  of  ser i al  d ata  f r omc om put e r e quipment  t othe t wist e d p airlin k, r eceiv e streams ofser iald ata  from  thetwis te d pai r link  andtr ansmit data tocomp uter equi pme nt , d et ect c o llisio nsonthe net work du e  to  a n o t he r MAU transmitting  c o n cu rrentlywith t h elo c al MAU,ve rif y th a t  theMAUa nd  AUI are  conne c te d,  automa ti callyin ter rup t the tran smit f unctionby in h ibiting a long data stream,a nd t ot estand  disable arece i ve l inki fthe linkis fa ul t y. The chief disadvant ag e of 1 0Base -T is that it  requiresa n external  hub ,  e a ch port of whi ch ca n only con n ect to o ne no de. Howe ver, oneo f  the mai n a dva nta ges o fusing 10Base- T medi um  is avo idi ng thecos t a ndinc on venienceof routi ng  c ab le  to  each node sin ce  te le pho ne-gr a de twi stedpair  w ir i ngalready ex i s ts i nmo st b uil di ngs a nd i s  th erefore  easier t o u s e th an  c oaxialcable or opti ca l fiber. S in ce10Base - T  require s 4 wires (two twistedw ire pai rs)  foreach  node, th e s upplyofe xistin g wiri ng in  a  bu i l dingm a ybeus ed up quic k l y.If tw onode s are l ocated in a room t h atonly has one10B ase- T co nne c ti o n ( tw o  pa i r s of wires), tw o addition al pa irs of wir e s m us t be ro uted to  thel ocation  to conne ct the se co nd n o d e t o the hub,  thus de feating o n e oft he  adva nta ges of  u sin g exi stingt wis ted p air wi ri ng.
In  addi ti on, each  node added uses up anadditi onalpor t on a hu b,t her eby requi ring  the insta lle r t o pur cha s e anappr o pr iat e  numb er o f  hubs tom at cht h enumber of n o d e s.If th e n u mber o f no des exceeds the n u mber of portson a h ub,  an addi ti onal hub mustbepu r c hased to  a ccommodatethe node sa nd th e expe nse of  the re m a in i ng unu sedpor ts is los t.Fo r  instal la ti o ns tha t ha ve  stand ardize d  on1 0 Base-T, the incr easin g numbe r  of  node sthat mu s t be  added tothe network  becom es a  majo r probl em . Curr ent  a lternative methods o f add ing nod es  toa 1 0Base- T al s o  have  the ir  di fficultie s . 
F I G.  2 B  is  a b lockdi agra m illustr a ting a 1 0Ba s e-T net wo rkc o mprisi n ga c tive hub 2 30,  mini - h ub 240 and node s  2 3 2, 23 4, 236  and 2 38
 of_wire connecting_the node to its_own port_on_the hub._This_type of wiring_is usually referred_to as either a_star-topology or structured_wiring,_and is used by most telephone systems.
IEEE Standard 802.3 for 10Base-T Twisted Pair Ethernet_defines_the functional,_electrical,_and_mechanical specifications for the 10Base-T_MAU and the medium. A_10Base-T MAU_handles message flow between computer equipment or hub_(repeater)_and a twisted_pair link. The MAU must be able to transmit_streams of serial data from computer_equipment to the_twisted_pair_link, receive streams of_serial data from the twisted pair_link and transmit data to computer_equipment, detect collisions on the network due_to another MAU transmitting concurrently with_the local MAU, verify that_the MAU_and AUI are connected, automatically_interrupt the transmit_function by_inhibiting a long_data stream, and to test and_disable a receive_link if the link is faulty.
The_chief_disadvantage of 10Base-T_is_that_it requires_an external hub,_each_port of_which_can only connect to one node._However,_one of the main advantages of using_10Base-T medium is avoiding_the_cost and inconvenience of_routing cable to each node_since telephone-grade twisted pair wiring already_exists in_most buildings_and is therefore easier to use than coaxial cable or optical_fiber. Since 10Base-T requires 4 wires_(two twisted wire pairs)_for each_node,_the supply of_existing_wiring in_a building may be used up quickly._If two_nodes are located in a room_that only has one_10Base-T_connection (two pairs of wires), two_additional pairs of wires must be_routed to the location to_connect_the_second node to the hub,_thus defeating one of the advantages_of using existing_twisted pair wiring.
In addition, each node added_uses_up an additional port on a_hub,_thereby requiring the installer to purchase_an_appropriate_number of hubs to match_the number of nodes. If the_number of nodes exceeds the number of ports on_a hub, an_additional hub must be purchased_to_accommodate_the nodes and the expense of the remaining unused ports_is lost._For installations that_have standardized on 10Base-T, the increasing number of nodes that_must be added to the network becomes_a major problem. Current alternative methods of adding nodes to a_10Base-T also have their difficulties.
FIG. 2B is a_block diagram illustrating a 10Base-T network comprising_active hub 230, mini-hub_240_and nodes 232, 234, 236 and 238