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ڽĽдڲٵ⣬ӹɵһǣչ˽ǽ֮Чİ취Ӧû죬û˻ڿֻǿһǰᡣ
˵ĿǰҵĽѾ˲̶ͬȵĹ˻Ǵֻ֧ԻΪխҵӦΪ㷺IDLCϵͳ˽Ŀһֵ˼⡣
˽ҪԷΪ֣Դ룬ԴԼڹͬHFCCable ModemSDHڽеӦڸֿ˽УSDHϵͳӦձġϵͳɳ֮ΪԴ룬ҪΪԴ磨PONĽϵͳԱȡ
ֱ20ĩ55ûĹ˲õSDHSDHԴ2090Ѿһֳ졢׼ļڹǸб㷺ãҼ۸ԽԽ͡ڽӦSDHԽSDHںеľ޴ƺͼƴ򣬳SDHͬá׼Ĺӿڡǿ͸߿ɿԴĺôڽĽ跢չг档 
ǣʹõĻʽSDH豸ΪƵģֱӰᵽʹûȽϰ󣬽ҪSDH豸ӦС͡ͳɱڰװάģӦȡһЩ򻯴ʩϵͳɱߴЧʣңеSDHѾûԵʽӿڵԶԶڶԸʽӿڵˣеSDH豸ӦṩSTM-0ʽӿڡ
SDH·չǶIPҵ֧֡SDH豸䱸LANӿڣSDHͳɱLANϣṩSDH֧·ӿڼ侻ӿڲƥ⣬Ҫҵû͹˾ûṩ͸LANҵISP룬ʺĿǰҵٷչĿǰһЩңѶ豸 
ATMԴ磨ATM PONڿ˽뼼УӪߺ豸Ӧձ鶼ΪATM PONЧģṩͳҵṩȽýҵĿƽ̨1995꿪ʼһЩӰӪߺ豸Ӧ̾ͿʼATM PONΪļȫҵFSANҪͼ淶FSAN֯20ڿϵͳɹʶĵŹ˾豸ӦɣNTTBTBellSouthͷŵȡ19988£ITUFSANĻPONĿ淶ƶ˽G.983.1 
ATM PONҪصԴ㵽ʽṹûԴԴĹͭ򵥣ӿɿάرFTTH˵ңʹãԴ͵ԴϵͳתƵڣ豸ĻҪԴ󽵵ͣάڿԼӳάɱĽͣսʹӪߺû˫档
APONı׼̶ȺܸߣʹôģͽͳɱΪܡ⣬ATMͳƸõصҲʹATM PONܱTDMʽPONڸûATMQOSҲԼ̳СĿǰATM PONNTTձBellsouthһЩ͵ϵͳ⣬ûеõܴ÷չҪԭAPONĳɱӸ߲¡NTT1995һԤ⣬Ϊ2000APONÿԳɱͭ߳ɱɱȣʵ֤APONĳɱûԵ½ơ
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˾Ե⣬ATM PON⡣G.983ATM PONϵͳҪԿҵ񣬲ûпǶխҵ֧֡խûпǶխҵ֧֡խҵҵۺڻATMĴƽ̨һֵ˼⡣APONӦFTTC£APON+IDLCһֱȽʵʵĽIDLCϵͳۺխҵAPONONUṩҵխҵV5ӿڵ·棬խͨصķʽFTTH/B£ONUû٣ַʽͲã迼 
⣬ԴϵͳһATM PONϵͳĿǰҲﲻFTTHӦó̶ȣͬҪϽ߿⡣Cable ModemڻϹͬHFCϷչġߵӵռͬ»Ѿ뻧һߵӹ˾Ƴ˻˺ͬ»Ľ뼼HFCͬŲгHFCֵĳҪڴͳҵĴ͡ǣطʧܣĿǰߵӪѾHFCϴʹͳҵתCable ModemHFCϽݴ䣬ṩInternet룬롣 
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ߵӹ˾µĵӪ˾˵Cable Modemǽгѡ񣬶Ӫ˾߼ҵƵԭADSL뼼֮ʵϣӴĽǶCable ModemھûĿ룬ڴͼȷ涼кܴơڴϣCable ModemûݴÿһŵͨԴﵽ25-40Mbit/sڵ㾡ûϵͳûʱƽǳԡCable ModemĿͨʻﵽٷ֮٣ADSLʹĿͨʵ͵⣬ֻΪûÿûĿݴ 
Cable ModemĲֵ֧绰ҵ񣬵Ȼָǵżĸ֤ĵ绰ҵ񣬶IPʽCable ModemϵͳϴʵʱҪĲ֮ҪеߵʵCable Modemߵ˫죬ʹ֮Ϊ߱˫ͨ磬һΪͶʡ
ǣһЩ˵绰ʽCable Modemõ¿ٴݣõ绰ߴݣֹʽҪеߵ˫죬˫Ѿ赽ľ绰ʽCable ModemнϴķչǱMCNSҲƶCable Modemı׼ȻCable ModemߵӲӪгҪֶΣӪҲӦּƺԣûʵչ뼼ʱûҵĵطCable Modem䲻㣬һҵ˫򿪷ţԵõ档ҵҵۺڻATMĴƽ̨һֵ˼⡣APONӦFTTC£APON+IDLCһֱȽʵʵĽIDLCϵͳۺխҵAPONONUṩҵխҵV5ӿڵ·棬խͨصķʽ
FTTH/B£ONUû٣ַʽͲã迼⣬Դ˽ϵͳһATM PONϵͳĿǰҲﲻFTTHӦó̶ȣͬϽ߿⡣    
     