VNC (vit tt ca Virtual Network Computing).Nguyn tc hot ng ca VNC ging nh Remote Desktop ca Windows,Phn mm VNC c 2 phn: -VNC Server ci t trn my tnh dng lm my ch. -VNC Viewer ci t trn cc my tnh s truy xut n my tnh chy VNC Server. N cho php nhng ngi ngi trn my tnh c ci VNC Viewer trong 1 h thng mng v internet thc hin mi thao tc trn my tnh c ci VNC Server. iu c ngha l gi s 1 my tnh TP.HCM c ci VNC Server v 1 s my tnh H Ni c ci VNC Viewer, thng qua internet nhng ngi H Ni c th thc hin mi thao tc y nh ngi trn my tnh ti TP.HCM. VNC c nhng c im nh sau: -VNC c th remote(tm dch: iu khin) gia Linux v Windows,t Linux c th xem v iu khin my windows v ngc li.So vi Remote Desktop ca windows, khi Linux mun s dng Remote Desktop ca windows bn bt buc phi ci thm dch v Remote Desktop onnection Linux remote thng qua web do Microsoft cung cp. -VNC chy nh mt service (TD : dch v ) nn khi bn logout vn remote c.So vi Remote Desktop ca windows bn phi lock user ang logon vo my .C ngha l i vi Remote Desktop ca windowsXP khi user ang lm vic ( ang logon) mun remote t xa bng ti khon user bn phi ngng lm vic (logoff). + Nu dng Remote Desktop ca windows server 2003 th hay hn XP n cho php ta c 3 phin lm vic t xa v 1 phin lm vic ti ch,ch khng nh Windows XP nu dng phin lm vic t xa th phi ngng lm vic phin ti ch. +Nhng 2 phin bn windows ny nu dng Remote Desktop th my ngi cho php remote khng thy c desktop(mn hnh) ca mnh m ngi c php remote ang lm g v ngc li. - Nu my tnh c ci VNC th ngi ngi trc my tnh VNC Server ( cho php remote) v tt c nhng ngi ngi trc my tnh VNC Viewer (c php remote) u nhn thy desktop(mn hnh) v u cng nhau thao tc c trn my tnh cho php remote. -VNC l cng c viewer khng lu li bt c trng thi ngoi lai no.C ngha l bn c th t cc my VNC Viewer (c php remote) bn c th b my ny i sang my khc lm tip mt cng vic m mnh ang lm dang d lc trc,trong khi con tr vn y nguyn v tr c. - Nhng c iu bt tin l khng m ha ng truyn nn s dng hi nguy him khi public VNC server ra ngoi internet. Bn hy vo y ti cc bn ci t cho cc HH khc http: //ww.realvnc.com/products/download.html .Bn ti cc bn Free v dng lm quen Phn sau ti s hng dn cch ci v s dng trong mng ni b, cch a ra ngoi internet,cch che du trnh ngi khc xm nhp m khng c php. Sau y ti hng dn ci trn windows

1.Ci t dnh cho VNC Server (My cho php remote): Chy file ci t m bn ti v cho n lc hin ln nh hnh bn di,n s hi bn la chn g bn hy chn VNC Server v nhn Next cho n khi Fishned.

M VNC Server ln cu hnh cc thng s.

Mt s chc nng chnh nh sau : Tab Authentication : C 2 mc bn la chn - No Authentication : nh du vo y nu mun my VNC Viewer khi kt ni vo VNC Server khng cn in password - VNC Password Authentication : nh du vo y sau click chn Configure sau bn in password vo, y l password m my VNC Viewer phi in vo kt ni vi my VNC Server. Tab Connections : bn ch hng s 5900,y l port(cng) mc nh ca VNC.Phn sau ta s ni thm mc ny.

Hnh minh ha port(cng) mc nh ca VNC Tab Inputs : Cho php my VNC Viewer dng chut,bn phm ...

Tab Sharing : Nu bn mun cho php hn 1 kt ni tr ln n VNC Server th nh du chn dng Always treat new connections as shared

Ngoi ra bn c th ty chnh cc Tab khc ty theo nhu cu ca mnh. 2.Ci t dnh cho VNC Viewer (My c php remote): Ging nh ci t VNC Server nhng bn chn mc ci t l VNC Viewer.Hnh bn di.

Bn c th ci ng thi VNC Server v VNC Viewer trn 1 my ty theo nhu cu s dng. 3.Hot ng mng Lan : Khi trn my c ci VNC Viewer khi kt ni vo VNC Server n s bt bn khai bo thng tin v my VNC Server.

Hnh minh ha cch truy cp vo my VNC Server t my VNC Viewer in IP ca my VNC Server m mnh mun kt ni trong Lan vo hoc in tn my cng c.Nu bt in password th ta phi in vo ty theo bn cu hnh my VNC Server. Hnh bn di minh ha my VNC Viewer kt ni vo VNC Server trong khi trng thi my VNC Server cha c logon.

Nh hnh trn khi bn click chut phi vo Themes (thanh di mu xanh nht ) ca my VNC Server n s a ra 1 danh sch cc mc bn hiu chnh khi tng tc vi my VNC Server.

Chng hn khi chn Send Ctr+Alt+Del n s m ca s logon ca my VNC Server bn ton quyn s dng trn my ny, y nh bn ngi trc my VNC Server. Khi dng VNC nu kt hp vi cc chng trnh Voice chat v Text chat nh Skype hay Yahoo Messenger trao i kin thc trong mt nhm,thm ch c th dng ging dy t xa th rt l tng.Ch mt tr ngi duy nht l .... "t mng" internet. Bn thn ti vn ang s dng ng thi VNC v Skype kt ni vi nhng ngi TP.HCM,H Ni,Hu...Cn mt iu bt tin ca VNC m ti qun ni trn l khng ti u ha bng thng bng cch nn nn hnh nh desktop ca my VNC Server khng hin th y cc bit mu trn my VNC Viewer. By gi ti ni s qua lm cch no cc my ci VNC "nhn thy nhau" qua internet. + Mi thit b nh my tnh ,Printer server (my in mng), modem ADSL,....khi kt ni vi nhau s c mt a ch IP + a ch IP ca cc thit b trong mng Lan khc vi a ch IP bn ngoi internet. + Trong mi trng internet cc thit b ch "nhn thy nhau" qua a ch IP "ngoi" ca modem ADSL, cc a ch IP ny c cp bi cc nh cung cp dch v internet nh VDC,Viettel... + Ta phi c bc chuyn tip t IP ca my tnh ci VNC Server thnh IP "ngoi" ca modem ADSL.Qu trnh ny mi ngi thng gi l Forward port v Nat port. + xc nh IP "ngoi" ca modem bn c th vo cc a ch sau : http://checkip.dyndns.org/ ,http://www.cmyip.com/ ,v cc nh cung cp dch v internet u cung cp cho ta IP ng .Bn nht nh phi bit a ch IP ny v gi cho ngi s dng my VNC Viewer, my VNC Viewer truy cp vo my VNC Server qua mi trng internet.Nu bn mun c a ch c nh bng tn, bn c th s dng cc dch v min ph nh http://www.no-ip.com , http://www.dyndns.org .Lc no c dp ni v thit lp h thng tng la, VPN, Web server v Mail server... dng ring cho mt tp th hay n v ti s ni v vn ny chi tit hn. + Ci ny hi kh hiu i vi nhng bn cha lm cc vn lin quan n qun tr mng, mc d ti c gng s dng 1 s cm t ngoi chuyn mn.Nhng cc bn c trc tip lm ri t t s hiu. Bn thn internet l mt mng ton cu kt ni hng t my tnh vi nhau,chc nng modem ADSL nh l mt router "cng" n c nhim v "bt tay" gia 2 mng vi nhau.V d : my tnh c ci VNC Server khi xem card mng c IP l 192.168.2.100,cc my tnh khc trong mi trng internet mun nhn thy n phi thng qua IP ca nh cung cp dch v internet chng hn nh IP 222.254.139.77 (IP ny c coi nh l IP "ngoi" ca modem ). Ti xin ni tm li cc trn.Nu mt my ci VNC Viewer(c php iu khin) kt ni c vi my VNC Server ( cho iu khin) th bn phi tm cch chuyn tip IP ca my tnh ci VNC Server thnh IP "ngoi" ca modem ADSL.Cn my ci VNC Viewer khng cn phi lm g thm c. Di y l hnh nh minh ha cch Forward port, cu hnh cng ty thuc vo tng hiu modem.

Bn nhn hng th 3 hnh trn ti ang NAT port 5900 my ci VNC Server c IP trong mng Lan l 192.168.2.100.Khi bn mun my c ci VNC Viewer truy cp vo c my VNC Server trong mi trng internet bn hy vo cc trang web http://checkip.dyndns.org/ hoc http://www.cmyip.com/ xc nh IP "ngoi" ca modem v thng bo n my c ci VNC Viewer IP ny bng Skype hoc Yahoo Messenger.Bn xem li Hnh minh ha cch truy cp vo my VNC Server t my VNC Viewer trong mng Lan, nhng trong mi trng internet bn phi in IP "ngoi" ca modem.Mi tng tc t my ny qua my kia cng ging nh trong mng Lan. V c bn bn c th thc hin mi thao tc t xa d bn bt k ni u min l c ng truyn internet. Nh ti ni lc trc,VNC c iu nguy him l khng m ha ng truyn,nn trn internet hin gi cc hacker ang s dng mt cng c (ch dng ring cho xm nhp my VNC Server) c chc nng scan nhng IP no ang dng VNC Server vi port 5900,tip n capture gi d liu ( TD : "thu li gi d liu" ) c truyn i t my VNC Server ( qa trnh ny nu s dng cc cng c ri rc th rt lu v hacker phi "cao tay") ,do khng c m ha nn h gii m rt d dng gi d liu c truyn i ly password VNC Server,vic cn li ca h l m VNC Viewer ln thoi mi truy cp vo my VNC Server. Theo ti bit cng c ny c im yu l khi chng ta i port 5900 thnh port khc chng hn nh 5943 chng hn th cng c ny mt tc dng tnh nng t d tm.V vy bn c th vo li tab Hnh minh ha port(cng) mc nh ca VNC thay i li port .V vy khi my VNC Viewer truy cp vo my VNC Server trong mng Lan hay trong mi trng

internet bn phi in thm port m mnh thay i.V d : 192.168.2.100:5916 hoc mi trng internet l 222.254.139.77:5916 Sau bn lm tip cc bc sau y cho an ton.Vo Tab Authentication nh du vo dng Prompt local user to accept connections nh hnh bn di

Khi nh du vo y tc dng ca n l ngi my VNC Server nhn thy c IP ca ngi ang truy cp vo my VNC Server v c quyn cho php ai c php truy cp vo.

Li dng tnh nng ny bn c th dng Skype hay Yahoo Messenger hi IP ca ngi m bn cho php truy cp, quyt nh chn Accept hay Reject. thc hin cc bc trong mng Wan cho quen dn,nu bn c 2 my tnh bn c th t mt mnh lm khi cho 2 my VNC Server v VNC Viewer u kt ni internet.