C 6 N G NGHE IJNG DUNG
Hinh 1. Du'dng cao toe tai thanh pho Los Angeles
MANG TRUYEN THONG:
nhu'ng ddi thay mtfi
M
ang truyen thdng dadc xem nha dadng cao toe. Chiing ta can nd, nhang nhu'ng ngadi thi/c si/ nghT ve nd la ai? Neu chiing ta khdng col mang truyen thdng mang tam quan trpng chien lade thi chiing ta se dong lai mot the gidi hoan toan mdi ve kha nang t i / dong hda va hieu qua.Trong thap nien 1950, da cd rat nhieu con dadng, va thadng mai phat trien manh tai Hoa Ky. Khdng phai la hai long vdi hien trang, tong thong Dwight Eisenhower da dan dau trong mot no li/e de thiet lap he thdng xa Id lien tieu bang. Tren thi/c te, Eisen- hower tao ra mot dadng dan Idn hdn cho thadng mai eiia Hoa Ky.
Hoa Ky ngay nay la mot quoc gia khac biet nhd nhi/ng xa Id lien tieu bang. Vao nhi/ng nam 1950 thi ai cd the di/ doan dadc dieu dd: nhd vao cac xa 16 lien tieu bang ma mot xa Id Idn hdn la thadng mai va xa hpi da thay doi.
Tinh hinh tadng td cung dang ton tai giCfa hien trang mang truyen thdng va nhu'ng vien canh mdi. Hau het cac mang Ethernet cong nghiep truyen thdng hien nay cd thdng ladng len den 100
Mbps - mot con sd khd tin noi chi mot vai nam trade day. Nhii'ng ai se chpn viec lai xe 10 dam/gid trong khi cd the lai d l dang va an toan vdi toe dp gifp 10 Ian? AI se chpn viec lai xe tren dadng hai Ian xe khi nhOtig cao toe 12 Ian dadng da s i n sang?
Bang tan la mot dai tan so nao dd dadc gidi han bdi mot tan sd thap nhiit va mot tan sd cao nhift. Bang thdng la bang tan dadc gan cho mot ngadi sd dung nao dd de truyen/nhan du' lieu. Neu col bang tan la mot xa Id thi bang thdng la chieu rpng ciia mot Ian dadng.
Nhu'ng khai niem tadng dadng vdi viec lai xe 100 dam/gid vdi xa Id 12 Ian xe dang trd thanh hien thi/c vdi cac mang truyen thdng cong nghiep. Cac the he tiep theo ciia mang truyen thong Ethernet cong nghiep se cd bang thong la IGbps - gap 10 Ian so vdi ngay hdm nay. Dieu nay se cd nghTa the nao cho cac hoat dong ciia nha may?
Vdi bang thdng Idn 1 Gbps, se khong chi de dang kiem soat toe dp t a dong hda, ma thi/c te cdn khong gidi han kha nang thu
16| TU DONG HOA NGAY NAY • (S6 114 - 4/2010)
CONG NGHE U'NG D U N G
R e m o t e O p e r a t i o n O f f i c e
Ethernet Data G a t e w ^ Serial M edia Converter Ethernert to Fiber
M e d i a Converter
Factory F(o*
W e b B r o w s e r ^^Aer
HMI S C A D A Software dust rial ub< Switch
C«sntral Control Room
Ftetdibijs
F i e l d E q u i p m e n t
Hinh 2. Mang Ethernet cong nghiep
thap di/ lieu cho viec truy xuat thong tin ve san xuift, cai tien quy trinh san xuat, bao tri va theo doi cac sai hdng. Moi bit thdng tin can thiet cho cac viec dieu khien, hieu, di/doan, phan i/ng va chii dong thay dd'i se deu sin sang mpi liic mpi ndi.
Hdn ca tdc do: bdng thdng
The he mdi ciia truyen thdng cong nghiep Ethernet 1 Gbps se khdng yeu cau thiet bi chuyen mach ton kem va nhan vien can dao tao ky ladng ve IT hoac Ethernet nha ngay nay. Si/ cai tien
Vf O ^
Bus Ring
^ XK
ExtaiKlad Star Hltrarchical Hinh 3. t^ot so vi du ve topo mang
Mesh
se thay d cac cap Ethernet thadng mai san cd, cae ket noi, va cac hub ddn gian se dadc tieu chuan hoa d cap thiet bi cho hoat dong d 1 Gbps. Ve cd ban, cac he thdng gia tri cao hdn se d l dang dadc bao tri bdi nhan vien nha may
Cac mang truyen thdng the he mdi cung se cd cac topo vdi tinh nang linh hoat cao. Nhan vien nha may se cd the ciiu hinh cac mang truyen thdng mot each thich hdp nhiit cho hoat dong san' xuat, lam cho nd d i dang hdn khi them phan ci/ng vao mang hay la cac nhu cau mdi phat sinh. Mang se cd kha nang ket ndi ndng P&P va kha nang ket hdp mang 1 Gbps vdi mang 100 Mbps.
Cac khia canh thii vi ve the he tiep theo ciia mang truyen thdng la chiing ta cd the khdng hoan toan di/ doan dadc tat ca cac phadng thi/c ma chiing se giup ta thay dd'i kha nang che tao va san xuiit. Chung ta se thiiy trade khi hoan toan hieu tat ca nhifng gi cac mang mdi se cho phep chiing ta lam.
Cac quan tri vien ciia nha may khdng dadc ngoi chdi va y lai vao mang truyen thdng hien tai. Hp phai hieu mang truyen thdng la cd sd ha tiing ciia tadng lai, tadng td nha cac xa Id lien tieu bang eiia Hoa Ky trong thap nien 1950. Neu chiing ta bd qua thi/c te nay, hoac ddn gian chi quan tam vdi cac tfnh nang mac dinh nha cung cap gi/i cho ma khdng xem xet li/a chpn khac, thi nghTa la da dat cong ty vao tinh the bat Idi trong canh tranh.
KHANH LINH (Theo www.cclinkamerlca.org)
(S6 1 1 4 - 4 / 2 0 1 0 ) ' < T I / D 6 N G HOA NGAY NAY |17
