HPメーカー180 Degree Turnの使用説明書/サービス説明書
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1 2005/03/11 ( C) Herbe rt Haa s The Ethe rnet Ev olution The 180 Degree Turn.
2 “Use common s ense in r outing cable. Avoid wrappin g coax around source s of strong electric or m agnetic fields. Do not wrap the cable around flourescent light ballasts or cyclotrons, for exa mple.” E thernet Headsta rt Product, Information and Ins tallat ion Guide, Bell Technologies, pg.
3 3 (C) Herbe rt Haa s 2005/03/11 History : Initi al Idea Shared media CS MA/CD as access algorithm CO A X Ca bles Half duplex communication Low latency No networking nodes (ex.
4 4 (C) Herbe rt Haa s 2005/03/11 Histor y: Multi port Rep eaters Demand fo r structu red cabl ing (v oice-g rade twist ed- pair) 10BaseT (C at3, Cat 4, .
5 5 (C) Herbe rt Haa s 2005/03/11 Histor y: Bridges Store a nd forw ar ding accor ding des tinati on M AC address Separa ted c ollisio n domains Improved netw ork performan ce Still one broad cast domain Thre e collision domains in this example ! Bridg es were i nvent ed fo r perf orman ce r easo ns.
6 6 (C) Herbe rt Haa s 2005/03/11 Histor y: S w itches Switch = Multiport Br idges with HW acceleration Full duplex Collision-free Et hernet No CSM A/CD necessary any more Differen.
7 7 (C) Herbe rt Haa s 2005/03/11 Today No coll isions no d istance li mitation s ! Gigabi t Ethernet beco mes W A N technology ! Over 10 0 km link s pan alre ady Combine sev eral .
8 8 (C) Herbe rt Haa s 2005/03/11 What About Giga bit H ubs? Would limit network diameter to 20- 25 meters (Gigabit Ethernet) Solutio ns Fram e B ur sti ng Carri er E xten sio n No.
9 9 (C) Herbe rt Haa s 2005/03/11 MAC Cont rol Frames A dditional functiona lity easi ly integrated Curr en tly o nly Pause-Frame supported preamble FC S MAC-ct rl par amet ers MAC-ctrl op cod e 8808h SA DA 8 bytes 6 6 2 2 44 4 Al w ay s 64 bytes MAC-ctrl op cod e .
10 10 (C) Herbe rt Haa s 2005/03/11 Auto Ne gotia tion Enables each t wo Ethernet dev ices to exchange info rmation about the ir capabi lit ies Signal rate, CSM A /CD, half- or f ull-duplex .
11 11 (C) Herbe rt Haa s 2005/03/11 Fast Link Puls es Modern Ethernet NICs send bursts of Fast-Link-Pulses (FLP) consisting of 17-33 NLPs for Autonegotiation signa lling Each representing a 16 bit word GE sen ds se ver al "pa ge s" A series o f FLPs constitute an autonegotiation frame.
12 12 (C) Herbe rt Haa s 2005/03/11 100 Mbit Ethernet O verview Fast Eth ernet 100Base 4T+ Signaling Fast Eth ernet 100BaseX Signaling 100BaseTX 100BaseFX 100BaseT4 (half duplex) 100VG-A nyLA N "100Bas eT" HP and AT&T inventi on for real t ime applicat ions IEEE 80 2.
13 13 (C) Herbe rt Haa s 2005/03/11 4B/5B Codi ng 4B/5B Encoder/Decoder PM A PCS MII 1 0 0 0 0 1 0 1 0 16 code groups 32 code groups 4x 25 Mbit/s 125 MBaud The diagram abov e shows the basic principle of th e 4B5B block coding principl e, which is used by 802.
14 14 (C) Herbe rt Haa s 2005/03/11 Gigabit Ethe rnet Media A ccess Cont rol (MA C) Gigabit M edia Independe nt Interf ace ( GMII) 1000Bas e-X 8B/10B enco der/dec oder 1000Bas e-T encoder /decoder 1000Bas e-LX LWL Fiber Optic 1000Bas e-SX SWL Fiber Optic 1000Bas e-CX Shielded Balanced Copper 1000Bas e-T UTP Cat 5e IEEE 80 2.
15 15 (C) Herbe rt Haa s 2005/03/11 GE Signa ling PMA PCS 802.2 LLC 802.3 CSMA /CD 802.3 PHY FC-4 upper lay er mappin g FC-3 comm on servic es FC-2 signalling FC-0 interface and me dia FC-1 enco der/de coder IEEE 80 2.2 LLC CSMA/CD or full dupl ex MAC PMD IEEE 80 2.
16 16 (C) Herbe rt Haa s 2005/03/11 GE 8B/1 0B C oding 8B/10B Encoder/Decoder PM A PCS GMII 256 code groups 1024 code groups 8x 125 Mbit/s 125 million code groups per second 1250 Mbaud 1 Only used by 1000Bas eX 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 8B10B block coding is ver y similar to 4B5B bloc k coding but allows full y balanced 10-bit codewords.
17 17 (C) Herbe rt Haa s 2005/03/11 1000BaseX T wo different waveleng ths suppor ted Full duplex only 1000Ba se-SX: short w ave, 85 0 nm MMF 1000Ba se-LX: long wa ve, 1300 nm M M F or .
18 18 (C) Herbe rt Haa s 2005/03/11 1000BaseT Defined by 802.3ab t ask force UTP Uses all 4 line pair s simulta neousl y for duplex transmission ! (echo cancellation) 5 level PAM codin.
19 19 (C) Herbe rt Haa s 2005/03/11 Several Physical Media S upported Logical Link C ontrol LLC MAC Control (optio nal) Media Access Control M AC PLS AUI P MA (MA U ) MDI Medi um Reconciliation Reconc.
20 20 (C) Herbe rt Haa s 2005/03/11 10 Gigabit Ethernet / IEEE 802.3ae Only optical support 850nm (MM) / 1310nm /1550 n m (SM only ) No copper P HY anymore ! Different implementation s.
21 21 (C) Herbe rt Haa s 2005/03/11 Note GE and 10GE use synchronous physical sublay er !!! Recommendation: Don't use GE ov er copper w ires Radiation/ EMI Grounding p r oblems High BER Thick cab le bund les (especia lly C at-7) Both GE and 10GE are synchronous ph y sical t echnologies on fib er.
22 22 (C) Herbe rt Haa s 2005/03/11 Summar y Ethernet evolv ed in the opposite di rection: Collision free W A N qualified Switched Seve ral coding sty les Comp lex PH Y archite.
23 23 (C) Herbe rt Haa s 2005/03/11 Quizz Why tends high-spee d Ethernet to synchronous PHY? Can I attach a 100 Mbit/s port to a 1000 Mbit/s port vi a fiber? What is the idea of Etherchann.
24 24 (C) Herbe rt Haa s 2005/03/11 Hints Q1: On fiber its difficult to deal with asynchronous transmission, phot ons cannot be buffered easily, store and forward problems Q2: No, autonegotiat.
デバイスHP 180 Degree Turnの購入後に(又は購入する前であっても)重要なポイントは、説明書をよく読むことです。その単純な理由はいくつかあります:
HP 180 Degree Turnをまだ購入していないなら、この製品の基本情報を理解する良い機会です。まずは上にある説明書の最初のページをご覧ください。そこにはHP 180 Degree Turnの技術情報の概要が記載されているはずです。デバイスがあなたのニーズを満たすかどうかは、ここで確認しましょう。HP 180 Degree Turnの取扱説明書の次のページをよく読むことにより、製品の全機能やその取り扱いに関する情報を知ることができます。HP 180 Degree Turnで得られた情報は、きっとあなたの購入の決断を手助けしてくれることでしょう。
HP 180 Degree Turnを既にお持ちだが、まだ読んでいない場合は、上記の理由によりそれを行うべきです。そうすることにより機能を適切に使用しているか、又はHP 180 Degree Turnの不適切な取り扱いによりその寿命を短くする危険を犯していないかどうかを知ることができます。
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