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Nguyen i'ran Quoc Vinh Tap chi KHOA HOC & CONG NGHE •71(9): 81 -87 MOT SO VAN DE TRONG XAY DLTNG HE THONG QUAN LY PHONG MAY CONG CONG ,, Nguyin Tran Quoc Vinh" Tnrdng Dai hoc Kinh li' - Dai hoc Dd \ dng lOM AT He thing quan ly viec sinh vien su dung may tinh tcii phong may cong cgng a cac tnrang dai hge la cin thilt Yeu clu chung dii vai mot he thong la tich hop tot dieu kien tang hien co, kha nang phat triln, ma rgng va sii' dung tai khoan ciia sinh vien de quan ly tii' ca sa du lieu thong nhat ciia truong Co thi noi cac he thing hien co tren thi truang khong dap img yeu cau Bai viet lam ro cac ky thuat cin thilt dl xay dung he thing quan ly phong may dam bao Ccic tinh iicIng: Quan ly thai dilni sinh vien su dung may tinh Quan ly thai lugng sinh vien su dung may tinh mien phi va theo the Quan ly cac dia chi internet ma sinh vien truy cap Cong cu de bat va tat may tinh tir xa theo y niuon ciia quan tri vien Til' khoii: Quan ly phdng mdy dich cu NT, truyin ihdng diep, che dp khdng ddng bg, dn lien trinh, hdt gdi lm vd dja chi hdt tdt mdy linh tirxa DAT VAN DE Yen ciiu cluing d6i voi be th6ng quan ly phong nuiy c6iig cgng lai mgt truiing dai bgc, la CO the sir dung l6l dieu kien tang hien co, sir dung tai khoan ciia sinh vien (SV) de quan ly tir co so dir lieu thong nhcit ciia truang Va sau day la cac yen can linh nang ciui yen: - Quan ly thai diem SV sir dung miiy linh - Quan ly thai lugng SV sir dung nuiy tinh mien phi va theo the - Quan ly cac dja chi internet nui SV truy cap - C6ng cu de bat va tat may tinh tir xa theo y muon ctia quan trj vien Nhin chung, yeu cau dciu lien va thir ba cho phep dap irng eac doi boi dang duge ap dung thuc lien eiia Thong tu lien tjch 02 Ve viec qiiciii ly diem truy cap Internet la Luu tru thong lin tiiy than khach hang va Luu trfr th6ng tin dja chi Web khiich himg truy Ccip Tim bilu mgt so he tb6ng chuong trinh thuong mai ciing nhu mien phi lien quan co mat tren thj truang INCMWin, icaffe, cho thay, hAu nhu cac phan mem quan ly Internet Cafe diu c6 dac diem chung ki thuang se khong luu dugc thong tin tinh lien nicil dien Vi vay, dl he thong kh6ng bj nuit lh6ng ' let: 0914 780898: Email iihiiiocvinhaymail com tin quan trgng mat dien, Ccic lac gia ciia cac chuong trinh khuyen cao khach hang nen sir dung bg luu dien UPS tai may chii Khi mat dien, loan bg tluing tin linh tien van ducic luu lai va co the thuc hien loan cho khach hang Phan tich mgt s6 chuong trinh khac nhu Nel Support for School, WinRoule, Wingale, cho thiiy, khong co mgt be tluing hay to hcip cac he th6ng chuong trinh nao dap irng day dil cac yeu cau dat Ngoai ra, cac he th6iig dong thi kli6iig the can thiep, phat trien mo rgng va tich hgp co' so du lieu eiia truang Ve lau dai, can phai tlurc bien cac nghien ciru thong ke viec sir dung may tinh ciia nhung nhom nguoi dimg - SV nao thong qua thai gian, thoi lugng, va hanh vi sir dung be lli6ng (chuong trinh trang web truy cap, ) ciia hg dugc luu lai co' sa dfr lieu Tren co' so ket qua cac nghien ciru c6 the lap ke hoach sir dung cac phong may hieu qua nhat ciing nhu nhac nlia/kliiiyen khich SV ve cac hanh vi sir dung phong may ciia hg Cac he th6ng ma ngu6n incV thi chii yeu dugc tao cho nen tang Linux, he tluing may linh ciia cluing la hau nhu chi su dung Windows Ngoai ra, co the se can tliiiit phat trien va tich hgp cac tinh nang mcii, nlur quan ly in an Fir nhung nhcin djnh tren co thi; 81 Nguyen Tran Quoc \'inh Tap chi KHOA HQC & CONG NGHE 71(9): 81 -87 ket luan nghien ciru xay dung mgt he th6ng mcii la Ccin thiet va cac iing dung mang de truyen dCr lieu, doc lap vai cac giao thirc mang dugc sii' dung M Q T SO VAN DE KY THUAT De dam bao CTMC co the lam viec cimg liic vai nhieu CTMT, tac gia da sir dung WinSock che kh6ng dong bg (asynchronous mode) Trong che d6 CTMC la mgt lien trinh - tien trinh chinh co the tao them m6t tien trinh de thuong xuyen kiem tra sir xual hien mgt th6ng diep den tir CTMT Va cho in6i mot th6ng diep nhan dugc tir CTMT mgt lien trinh nua dugc tao de dam nhan viec xu K' no Va bay gia, su xung dot sir dung tai nguyen giua cac tien trinh la hoan loan co the xay Tac gia sir dung lop Monitor va lockobject de dam bao su d6ng bg hoa truy cap den tai nguyen chung cua cac tien trinh Trong thiet ke \a phat trien bcit cir he th6ng nao deu co nhirng van de Mgt da giai quyet nhirng van de do, viec xay dirng he thong khong kho khan nira Theo cac chirc nang yen cau da dua ro rang, de xay dung he thong truac tien phai tra loi cac can hoi sau day: Lam the nao de may chu (MC) dai dien la chuong trinh may ciui (CTMC) va max tram (MT) dai dien la chu'O'ng trinh may tram (CTMT) co the "noi chuyen" \ai nhau? Thu thap cac dja chi internet ma SV da truy cap phien lam viec ciia minh bang each nao? Lam the nao de bat/tat hang loat cac MT chi bang mgt lenh tir mgt may khac? Ngan can SV tat CTMT nhu the nao? Dam bao truyen thong giiia CTMC va cac CTMT Hoan tOcin co the giai quyet \an de truyen th6ng gitia CTMC Vci CTMT lh6ng qua cac thong diep chira cac leiih,/yeu cau tir/den CTMC din/tir CTMT C6ng viec ciia CTMC la gui nhan, va xir ly th6ng diep den lir CTMT Can giai quylt viec d6ng bg boa qua trinh giri/nhan th6ng diep va xir ly ket qua de kh6ng xay tranh chap va loi he th6ng CTMC Cac m6i truong phai trien phan mem theo mac djnh thuang lao mgt chuong trinh moi chi bao g6m mgt lien trinh va qua trinh xii ly cau lenh chuong trinh xay mgt each n6i tilp Khi do, chuong trinh co the lam viec kh6ng hieu qua \ci dac biet co the gay loi mgt so irirong hgp Cach giai quylt la xay dyng chuong trinh da tien trinh (multi-threading) \ci dimg cac d6i tugng giiip dong bg hoa qua trinh truy cap den cac tai nguyen dimg chuna ciia nhieu lien trinh khac nhu mutex, semaphore, event, interlock thu vien WIN API Cac moi truong lap trinh deu CO Ccic lap khac trien khai Ccic chirc nang tuong irng Windows Sockets (WinSock) [1-3] cho phep Icip trinh de tao cac img dung Internet, IntraneL 82 Tuy CTMT chi dam bao truyen th6ng voi mgt dau in6i nhat la CTMC, Socket dugc sir dung no cung dugc tao che kh6ng dong bg Trong in6i lli6ng diep giua CTMC va CTMT chira mgt lenh la ni6t tii' khoa cimg voi cac th6ng s6 ciia no Lenh va cac th6ng s6 dugc phan each voi bang cac ky tu khoa De ban die truong hgp "tan c6ng tii' ch6i djch vu" dai ciia th6ng diep dugc gioi han th6ng qua cau hinh ciia CTMC Vi the, nhirng th6ng diep nhu danh sach dja chi SV da truy cap bay Ijch sir sir dung may tinh ciia SV co the dai hon so voi chieu dai gioi ban Chimg se dugc cat va giri den may nhan theo nhieu th6ng diep khac M6i thong diep dugc tinh t6ng CRC32 triroc giri T6ng dugc dinh kem voi thong diep Khi CTMC/CTMT nhan dugc thong diep tir CTMCT/CTMC n6 se kiem Ira long CRC32 ciia th6ng diep co dimg hay khong, Neu dimg no se tien banh xir ly Neu sai nghTa la th6ng diep vira nhan kh6ng chinh xac, no se bao lai cho ben giri ve sir kien de ben giii giri lai thong diep mgt lan nfra Trong truong hop th6iig tin giri di dugc xep vao loai nhay cam, chang ban login, mai khau, no se giri cho may nhan lh6ng diep qua kenh ma boa SSL Liic Uciy tinh CRC32 cho thong diep la dieu kh6ng ckn thill \ i thucit loan SSL da tinh den sir chinh xac Irong lru>en tai ciia thong diep dugc ma hoa Nguyen Tran Quoc Vinh Tap chi KHOA HOC & CONG NGHE Quan ly dja chi internet SV da truy cap Vi SV CO the sir dung nhieu chuong trinh khac nhau, co the co san tren MT, co the tai ve tir internet hay mang den tren cac luu trir USB la kh6ng the bat tat ea cac dja chi internet ma SV truy cap tli6ng qua phan tieh mgt s6 chuong trinh, ma can phai bat cac goi tin TCP/IP dugc truyen tai qua cac the giao dien mang (NIC) va phan tich T6n tai mgt s6 c6ng nghe de bat cac goi tin TCP/IP lieu bilu la Microsoft Filter-hook driver, FirewallHook Driver, NDIS - Network Driver Interface Specification va WinPcap - The Windows Packet Capture Library Filter-hook la mgt trinh dieu khien che hat nhan dugc sii' dung de Igc cac goi mang Chi nhat mgt filter-hook co the dugc cai dat tren he dieu hanh va dugc sii' diing boi cac bg Igc Irinh dieu khien IP Ta co the phat trien mgt luong lira hoac mgt monitor, nhung neu cac img dimg khac sir dung bg Ige va cai dat cac chirc nang trucic, cbiroiig trinh ciia cluing ta se kh6ng liuii ducjc bat cir dieu gi va ngugc lai Mac dii lai lieu hircing diin DDK noi rang, eo the truy cap goi ngi dung mgt bg Igc dang boat dgng Nhung tlurc te, la chi CO the truy cap g6i ngi dung cho cac goi nhan dugc, d6i voi Ccic goi da giri la chi CO the dgc diu FCP/IP, UDP Vci ICMP Muc dich ciia Firewall-Hook lii cte quan ly cac goi niciiig da ducic giri va nhan dugc tren mgt birc luang lira b6i canh ciia cac giao thirc TCP/IP No Cling co the can thiep vao hocit dgng ciia cac ket n6i chia se Internet (ICS), hoac mgt birc tuong lira ca nhan dang thuc thi I iiy nhien, no khong dap irng yen Cciu cua birc luong lira boi vi n6 chay tan qua cao mo hinh nicing Firewall-Hook kh6ng dugc khuyin cao de trien khai cho MS Windows XP va cac phien ban sau ciia he dieu hanh Ro rang, niu sir dung Firewall-FIook Driver thi se gap kho khan cho phat trien mo rgng he Ihong vl sau De cung Ccip chirc nang tuang lua tren Windows XP va cac phien ban sau ctia n6 nen Lio m6t trinh dieu khien trung gian miniporl NDIS de quan ly cac goi da giri vii nhan 71(9): 81 - Trinh dieu khien trung gian NDIS [4] lam viec tren giao dien giiia cac cap giao thirc dieu khien va trinh dieu khien miniporl No CO the dugc irng dimg de a) Bien djeh giu'a cac trinh dieu khien thugc cac tang khac nhau; b) Lgc du' lieu vi muc dich an ninh hay cac miic dich khac; c) Giai phap dieu chinh can bang tai (LBFO); c/) Giam sat va thu thap dir lieu lh6ng ke cua mang Mgt trinh dieu khien miniport true tiep quan ly mgt NIC va cung cap mgt giao dien voi trinh dieu khien mirc cao hon Hau nlur cac ung dung mang ii6i tieng deu irng dung NDIS Chang ban, kiem tra the Network Adapters Device Manager eiia MS Windows va cho hien tat ca cac thiel bj an ta CO the ihay Kaspersky Internet Security quan ly cac goi mang bang each tao cac NDIS Miniport cho tirng NIC Co the noi, NDIS co rat nhieu uu diem Tuy nhien, sir dimg no la hoan loan kli6ng don gian doi hoi rat nhieu c6ng sire khau lap trinh Dc dam bao cac yen cau dat ta co the sir dimg WinPcap voi su don gian hon lap trinh WinPcap [5] la lieu chuan c6ng nghiep cho cong cu cung cap kha nang truy cap mang thugc lap lien ket ni6i truoiig Windows: no cho phep cac img dung nam bat va truyen tai cac goi mang bo qua cae chong giao tluic va CO them cac tinh nang huu ich bao gom Igc goi cV cap hat nluin may tli6ng ke mang va c6ng cu Ii6 trg cho chup goi tir xa, WinPcap bao g6m mgt trinh dieu khien cho phep nici rgng he dieu hanh dc cung cap kha nang truy cap mang ci mirc thap, va mgt thu vien dugc sir dung de de dang truy cap vao lop mang cap thap Thu vien cfmg chira cac phien ban ciia Windows cung nhu phien ban dugc biet den rgng rai la libpcap UNIX API Nha sir phong phii ve linh nang, WinPcap lii may bat goi va c6ng cu Igc ciia nhieu cong cu mang ma ngu6n ma va thuong mai bao gom ca giao thirc phan tich, gicim Scil vii theo doi mang monitor, sniffer, luu lugng truy c;ip mang va c6ng cu kiem thir mang Mgt s6 nhung c6ng cu nay, nlur Icpdump WinDump, Wireshark, Nmap snort, nlop riil 83 Nguyen Tran Quoc Vinh Tap chi KHOA HQC & CONG NGHE 71(9): 81 -87 ket luan, nghien ciru xa\ dung mgt he th6ng moi la can thiet, va cac Ling dung mang de truyen du' lieu, dgc lap voi cac giao thuc mang dugc su' dung M O T S O VAN DE KY THUAT De dam bao CTMC co the lam viec ciing liic voi nhieu CTMT, lac gia da su dung WinSock che kliong dong bg (asynchronous mode) Trong che CTMC la in6l lien trinh - lien trinh chinh co the tao them mgt lien trinh de thuong xuyen kiem tra sir xuat liieii mgt lh6ng diep den tir CTMT Va cho moi mot thong diep nhan dugc tir CTMT mgt tien Irinh nua dugc tao de dam nhan viec xu' ly nci Va bay gio, su xung dot sir diing tai nguyen giua cac lien trinh la hoan loan co the xay Tac gia sir dimg lop Monitor \a lockobject de dam bao su d6ng bg hoa truy cap den tai nguyen chung ciia cac tien trinh Trong thiet ke \a phat trien bat cir he th6ng nao deu co nhting \an de Mgt da giai quyet nhiing \an de viec xay dung he thong khong kho khan nira Theo cac chirc nang yeu cau da dua ro rang, de xay dirng he thong truac lien phai tra loi cac Cciu hoi sau day: Lam the nao de may chu (MC) dai dien la chuong trinh may chii (CTMC) va max tram (MT) dai dien la chuo'ng Irinh max tram (CTMT) co the "noi chuyen" \ai nhau? Thu thap cac dja chi internet ma SV da truy cap phien lam viec ciia minh bang each nao? Lam the nao de bat/tat hang loat cac MT chi bang mgt lenh tir mgt max khac? Ngan can SV tat CTMT nhu the nao? Dam bao truyen thong giiia CTMC va cac CTMT Hocin loan co the giai quyet x'aii de truyen lh6ng giua CTMC \a CTMT tli6ng qua cac tli6ng diep chira cac lenh'yeu can tir/den CTMC dln,'tir CTMT Cong viec cua CTMC la gui nhan, va xir ly lli6ng diep den tir CTMT Can giai quyet viec d6iig bg boa qua trinh giri/nhan th6ng diep va xir ly ket qua de kh6ng xay tranh chap va loi he tli6ng CTMC Cac m6i truang phat trien phcin mem theo mac djnh thuong tao mgt chuong trinh mai chi bao gom mgt lien trinh \a qua trinh xu ly can lenh chirong trinh xay m6l each n6i tiep Khi do, chuong trinh co the lam viec kli6ng hieu qua va dac biet co the gay loi mgt s6 truong hgp, Cach giai quyet la xay dung chuong trinh da tien trinh (multi-threading) \ ci dimg cac doi tugng giiip d6ng bg boa qua trinh truy cap den cac tai nguyen dimg chung cua nhieu tien trinh khac nhu mutex semaphore, event, interlock thu vien WIN API Cac moi truong lap trinh deu CO cac Icip khac trien khai cac chirc nang tuong irng Windows Sockets (WinSock) [1-3] cho phep Icip trinh de lao cac img dung Internet IntraneL 82 Tuy CTMT chi dam bao truyen thong voi mgt dau m6i nhat la CTMC Socket dugc su dung no cung dugc tao Irong che kh6ng d6ng bg Trong m6i th6ng diep giua CTMC va CTMT chira mgt lenh la mgt tii' khoa cimg voi cac thong so ciia no Lenh va cac th6ng s6 dugc phan each voi bang cac ky tu khoa, De ban che truong hgp "tan c6ng tii' ch6i djch vu" dai ciia tb6ng diep dugc gioi ban th6ng qua cau hinh ciia CTMC Vi the, nhiing th6ng diep nhu danh sach dja chi SV da truy cap hay Ijch sir sir dung may tinh ciia SV, co the dai hon so voi chieu dai gioi ban Chiing se dugc cat va giri den may nhan theo nhieu tli6ng diep khac Moi th6ng diep dugc tinh t6ng CRC32 truoc giri T6ng dugc dinh kem vai thong diep Khi CTMC/CTMT nhan dugc thong diep tir CTMCT/CTMC no se kiem tra long CRC32 ciia th6ng diep co dimg hay kh6ng, Neu dimg no se tien hanh xir ly Neu sai nghTa la th6ng diep vira nhan kh6ng chinh xac, no se bao lai cho ben giri ve su kien de ben gui giri lai th6ng diep mgt lan nira Trong truong hgp th6ng tin giri di dugc xep vao loai nhay cam, chang ban login, mat khau, no se giri cho may nhan th6ng diep qua kenh ma hoa SSL Liic luiy tinh CRC32 cho th6ng diep la dieu kh6ng can thill, vi thuat loan SSL da linh den su chinh xac truyen tai ciia thong diep dugc ma hoa Nguyen Trcin Quoc Vinh Tap chi KHOA HOC & CONG NGHE Quan ly dja chi internet SV da truy cap Vi SV CO the sir dung nhieu chuong trinh khcic co the co san tren MT, co thi tai ve tir internet hay mang din tren cac luu tru USB ta kh6ng the bat tat ca cac dja chi internet ma SV truy cap th6ng qua phan tich mgt s6 chuong trinh ma can phai bat eac goi tin TCP/IP dugc truyen tai qua cac the giao dien mang (NIC) va phan tich T6n lai mgt so cong nghe de bat cac goi lin TCP/IP tieu bilu lii Microsoft Filter-book driver, FirewallHook Driver, NDIS - Network Driver Interface Specification va WinPcap - The Windows Packet Capture Library Filter-hook la mgt trinh dieu khien che hat nhan dugc sii dung de Igc cac goi nuang Chi nhat mgt filter-hook co the dugc cai dat tren he dieu hanh va dugc sir dung boi cac bg Igc trinh dieu khien IP Ta eo the phat trien mgt tircTiig lira hoac mgt monitor, nhung neu Ccic irng dung khac sir dung bg Igc va cai dat cac chirc nang truoc, chuong trinh ciia cluing ta se kli6ng liim dugc biit cir dieu gi va ngugc lai Mac dii Uii lieu hircing diin DDK noi rang, co the Iriiy ciip goi luii dung mgt bg Igc dang hoat dgng Nhung Ihuc te, ta ehi CO the truy cap goi ngi dung cho cac goi nhan dugc, d6i voi cac goi da giri la chi CO ihci dgc diu TCP/IP, UDP Vci ICMP Miic dich cua Fircvvall-Hook la de quan ly cac goi mang da ducic gui va nhan duirc tren mgt birc luang lira boi canh ciia cac giao thirc TCP/IP, No Cling co the can thiep viio bocat dgng ctia cac ket n6i chia se Internet (ICS), hoac mgi birc tuang lira ca nhan dang thuc thi I uy nhien, no kli6ng dap irng yen Cciu cua birc tuong Ilia boi vi no chay tan qua cao mo hinh iiuaiig Firewall-Hook kluing dugc khuyen cao de trien khai cho MS Windows XP vii cac phien ban sau ciia be dieu hanh Ro rcing, neu sir dung Firewall-Hook Driver thi sc gap kho khan cho phat trien ma r6ng he thong ve sau De cung cap chiic nang tuong lua tren Windows XP va cac phien bcin sau cua no, nen Uno mgt trinh dieu khien trung gian miniporl NDIS de quan ly cac goi da gui vii nhan 71(9): 81 -87 Trinh dieu khien trung gian NDIS [4| lam viec tren giao dien gifra cac cap giao thirc dieu khien va trinh dieu khien miniport No CO the dugc irng dung de a) Bien djch gifra cac trinh dieu khien tliu6c cac lang khac nhau; b) Lgc dti' lieu vi muc dich an ninh hay cac muc dich khac; c) Giai phap dieu chinh can bang lai (LBFO); ci) Giam sat va thu thcip dir lieu thong ke ciia mang Mgt trinh dieu khien miniport true tiep quan ly mgt NIC va cung cap mgt giao dien vcii trinh dieu khien a iiiiic cao hon, Hau nlur cac irng diing mang n6i tieng deu irng dung NDIS Chang ban, kiem tra the Network Adapters Device Manager ciia MS Windows va cho hien tat ca cac thiet bj an ta CO the ihay Kaspersky Internet Security quan ly eae goi mang bang each tao cac NDIS Miniporl cho tirng NIC Co the noi, NDIS c6 rat nhieu uu diem Tuy nhien, sir dimg no la hoan loan khong don gian doi hoi riit nhieu cong sire khciii lap trinh Dc dam bao cac yen can dat ra, ta co the sir diing WinPcap voi sir don gian bon liip trinh WinPcap [5] la tieu chuan cong nghiep cho cong cu cung cap kha nang truy cap mang thugc lop lien kel m6i truong Windows: no cho phep eac irng dung nam bat va truyen tcii cac goi mang bo qua ciic chong giao tluic, va CO them cac tinh luing huu ich, bao gom Igc goi a cap hat nhan, may thong ke mang va c6ng cu ho trg cho cluip goi tir xa WinPcap bao gom mgt trinh dieu khien, cho phep 1110' rgng he dieu hanh de cung cap kha nang truy cap mang a mirc thap, va mgt thu vien dugc su' dung de de dang truy cap vao lop mang cap thap Thu vien cung chira cae phien ban ciia Windows cung nhu phien ban dugc biet den rgng rai la libpcap UNIX API Nha su phong phii ve tinh nang WinPcap la may bat goi va c6ng cu Igc cua nhieu cong cu mang ma ngu6n ma va tlurong nuai bao gom ca gicio thirc phan tich, gicim siit vii theo doi mang monitor, sniffer, luu lugng Iruy Ccip nuang va c6ng cu kiem thir mang Mgt so nhung c6ng cu luiy, nhu Icpdump, WinDump, Wireshark, Nmap, snort, nlop riil 83 Nguyen Tran QuIc Vinh Tap chi KHOA HQC & CONG NGHE noi tieng va dugc su dung rat rgng rai cgng dong mang WinPcap so huu nhieu dac tinh dang chu y nhu mien phi, hieu qua boat dgng cao, ph6 bien rgng rai, da dugc kiem thir va dang tin cay de dang sir dung cho lap trinh vien cung nlur iigu'6'i dimg cu6i, dugc tich cue tri lien hau het cac he dieu banh hg Windows, de dang xuat khau cong cu UNIX hay Linux sang Windows va ngugc lai Mcit da bat dugc cac goi mang, ta co the phan tich chimg de dua dja chi internet ma SV truy cap tham chi, ca ngi dung cua cac goi tin Bat/tat may tram Co nhieu c6ng nghe khac h6 trg bat may tinh tir xa qua LAN (Wake on LAN) hoac Internet [6] Tac gia sir dung c6ng nghe ggi la Magic Packet [7] Magic Packet la mgt goi lin voi ngi dung byte OxFF kit hgp vai 16 lln dja chi MAC ciia NIC dugc gSn tren MT cin bat Magic Paket dugc giri cho toan mang LAN Khi NIC quet dugc Magic Packet voi dja chi MAC ciia minh no se bat may tinh Tat nhien, de NIC co the bat may tinh, muc Power Management ciia BIOS Setup, cin thill dat thugc tinh Wake On LAN vl gia trj True Xac djnh dja chi MAC ciia tit ca cac NIC LAN va them vao danh sach la c6ng viec kh6ng nuiy kho khan nhung doi hoi nhieu c6ng sire Dae biet, so lugng may tinh Ion va m6i co thay d6i NIC la phai dieu ehinh danh sach MAC Ta co thi quel lat ca cac nhom mang (WorkGroup) LAN, sau quel tat ca cac may tinh thugc moi nhom [8] D6i vai m6i may tinh, diing lenh SendARP [9] de nhan dja ehi MAC ciia no va luu vao danh sach de dieu khiln bat may linh tir xa diing Magic Packet De lat MT, tac gia xay dung mgt chuong trinh - djch vu NT va cai dat tren MT voi quyen quan Irj vien Chuong trinh tu dgng kel n6i den CTMC bang WinSock Khi nhan dugc lh6ng diep chira lenh tat may vai thong s6 la each thirc tSt may - PowerOff, Shutdown, Hibernate hoac Suspend, no se ggi chu6i cac lenh WinAPI dl tat may theo kieu cp buoc [10] 84 71(9): 81 -87 Ngan SV tdt CTMT Tb6ng thuong, cac he th6ng chuong trinh quan ly MT lam viec theo kjch ban sau Tai khoan Windows ma SV sir dung tren MT la lai khoan nguoi dimg bj gioi han chir khong phai la mgt tai khoan quan trj vien Va thuong, MT dirge cai dat de tir dgng dang nhap vao Windows bang lai khoan nay, Ngay sau do, CTMT se dugc khoi dgng va kh6ng che man hinh SV phai dang nhap c6ng vao he tb6ng quan ly th6ng qua CTMT thi hg moi c6 the lam viec, voi dieu kien tai khoan ciia hg cho phep Ngugc lai, CTMT se chiem loan b6 man hinh va SV khong the lam viec tren MT Van de dat la, neu SV tim each til CTMT lhi sao? Co the lira chgn "cam" chuong trinh Task Manager ciia Windows bang each thuc hien mgt s6 thiel dat he th6ng Registry ciia Windows dl SV khong thi tat CTMT Tuy nhien, lira chgn khong phai la diing dan Trong qua trinh sii' dung MT, co lhi ,xay nhieu van de voi cac chuong trinh img dung, chang ban, cac iing dung van phong bj treo la hoan loan co the Va SV can dimg Task Manager de dong nhung chuong trinh Ngoai ra, niu chii tam tat CTMT, SV co the su' dung cac e6ng cu khac mang theo, chu' kh6ng nhat thiet phai dimg Task Manager Chimg loi thuc hien cac buoc sau dl ngan ngira SV tat CTMT D I U tien, xac djnh tat ca cac chuong trinh quet danh sach tiln trinh, chang ban nhu Task Manager Sau giri th6ng diep he thing LVMDELETEITEM 6i xoa ten ciia CTMT tir danh sach tiln trinh ciia cac chuong trinh [ I I ] Nhu thi, CTMT kh6ng CO ten danh sach liln trinh va SV khong the tat no Tuy vay, SV van co thi tSt true tilp CTMT bang mgt cong cu nao chir kh6ng quet danh sach tiln trinh Nhu thi, CTMT "an minh" d6i voi cac c6ng cu kilu Task Manager la chira dii Giai phap dugc chgn la them tinh nang kilm soat viec tat CTMT boi mgt irng dung khac vao djch vu NT ciia MT da dl cap tren Vi dich vu NT lam viec duoi tai khoan quan trj vien Nguyen Tran Quoc VinI Tap chi KHOA HQC & CONG NGHE hoac he th6ng nen SV kb6ng the tcii no Khi SV tat CTMT no se bu6c SV thoat cua phien lam viee (Log Off) hoac khoi dgng ep buoc lai MT Kiem soat va thoat phien lam viec lui> khai dgng lai may kb6ng the hoan loan tha) the viec CTMT "an minh" d6i voi cac cong cu kieu Task Manager, vi no de dan den viec MT bj khai dgng lai thuong xuyen Lua chon cong nghe "fac gia lira chgn cong nghe WinSock de trao doi thong tin dua tren TCP/IP; ma boa d6i xirng va phi d6i xirng; CRC32 de kiem tra tinh dimg dan ciia thong diep nhan dugc; xiiil de luu ciiu hinh; lap trinh xir ly du lieu ODBC - Open Database Connectivity; thir vien WinPcap de bat cac goi lb6ng tin luu thong qua NIC; iig6n ngfr lap trinh C# va moi trircTng phat trien Visual Studio 2008 cho phep xiiy dung he th6ng de dang nhat, Ket n6i den iigu6n dfr lieu ODBC kli6ng phu thugc vao he quan trj co' so dir lieu Cac bang du lieu thugc ve rieng he th6ng nay, bang du lieu tcii khoan SV cfing nhu cac thao lac ciia he thong ducrc xay dung tren cac bang dfr lieu la don gian Vi the, co the lira chgn lap trinh xir ly dfr lieu ODBC, va no cho phep su dung bcit cir he quan trj ca so dir lieu hien co Ucio, Xciy dung he lh6ng He Uuing chuong trinh quan ly phong may va SV dimg be tli6ng may tinh cua trucing dai ligc lioim bao gom cac phiin chirc luing chinh va chia liiin giai doan phat trien sau day Quiin Iy thoi diem SV sii' dung may tinh Quan ly thai diem SV bat dciu su dung va ket Ihiic phien lam viec tren mgt MT cu the: - 'Uuing lin chinh Xcic ve MT nao da dugc sir diing dugc km gifr theo s6 MAC ciia NIC hocic la s6 sery cua cimg (nhung s6 kli6iig lap) - Thong lin lai khoan SV dugc sir dung tir co' so dfr lieu bg phan Dao tcio, Quyen truy cap de dcic (chi dgc, khong sira d6i, them, xoa) bg phcin Dao tao cung cap, - Khoang each giira hai kin Ccip nhat thong tin truy cap ciia SV len co sci du lieu quan trj vien quy djnh qua phan mem quan trj 71(9) - 8^ Chuong trinh bao g6m ba phan ki CTMC c6ng cu quan trj cau hinh CTMC va CTMT, - CTMC - Mgt djch vu he thong N'F tir d6ng khoi dgng va lam viec a cap he tli6ng chju trach nhiem lien lac voi cac MT va MC ca so' du lieu ciia bg phan Dao tao Neu mat kel noi den CO so dir lieu, CTMC se lien tuc thir ket noi den co' so dfr lieu theo nhfrng thong so da dugc quan trj vien cho trucic -Quan tri cau hinh CTMC cho phep quan trj tir xa hoac tren MC voi dieu kien ngiroi diing phai nhap dimg mat khau ciia quan trj vien No quan trj thong so ket noi gifra CTMC va CTMT, tli6ng s6 ket noi cua CTMC den co so dfr lieu cung nlur thong tin ve Ccic bang dir lieu, che bao mat lien lac giira CTMC va cac CTMT (SSL2, SSL3, PTL), giai ban s6 ket noi CTMC cho phep cimg mgt luc, toi da 50.000 mill kluiii de ma kboii cac C'FMT khoang tbcii gian gifra hai lan cap nhiit thong lin sir dimg M F cua SV -CTMT dugc cai dat va luon luon llurc thi tren M'F No chi cho phep SV lam viec neu SV nhcip dimg lining tin mgi tiii khoan co CO' so dfr lieu ciia bg phan Dao tao Neu nhap dimg miit khau dc; ma khoa quan trj vien quy djnh thi co the lam viec kh6ng can dang nliiip; cluic luing niiy nham pliiic vu ciic Icip bgc tai phong may Quan ly thoi lu'ong SV sii' dung may tinh mien phi va theo the - Moi SV dugc su dung mien phi mgt thai lugng mgt gioi ban ve thai gian nhat djnh dugc quy djnh theo tirng lop Cac giai luan dugc quy djnh bai mgt chucTng Irinh dugc cung cap la mgt phan ciia bg cong cii - SVco the mua the va kich boat the Co mgt chuong trinh rieng de lao cac the voi so the va mat khau ngau nhien theo cac th6ng s6 nguoi sir dung chuong trinh cho trucic nhu: menh gia, thai lugng va gioi ban so phai sir dung bet thai lu'cing Neu gcin kel tluic thai gian sir diing nhung tluii lucing van nhieu, SV CO the kich boat the khac de dirirc duoc phep su dung ca pluin chua sir dimg cua liii khoan The duoc ban a mot tluri diem vii 85 ... viec cimg liic vai nhieu CTMT, tac gia da sir dung WinSock che kh6ng dong bg (asynchronous mode) Trong che d6 CTMC la mgt lien trinh - tien trinh chinh co the tao them m6t tien trinh de thuong... Monitor va lockobject de dam bao su d6ng bg hoa truy cap den tai nguyen chung cua cac tien trinh Trong thiet ke \a phat trien bcit cir he th6ng nao deu co nhirng van de Mgt da giai quyet nhirng... truyen th6ng voi mgt dau in6i nhat la CTMC, Socket dugc sir dung no cung dugc tao che kh6ng dong bg Trong in6i lli6ng diep giua CTMC va CTMT chira mgt lenh la ni6t tii'' khoa cimg voi cac th6ng s6
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