O HA MY CHTrong nhng nm gn y, vi s ra i v pht trin mnh m ca thng mi in t v dch v trc tuyn, nhu cu v c s h tng cng ngh thng tin ang tr thnh mt vn cp thit i vi cc doanh nghip. Ngi dng ngy cng i hi nhiu hn: gi thnh dch v thp, h thng p ng nhanh, cht lng dch v n nh p ng c nhng nhu cu , gii php trit v lu di nht l nng cp c s h tng cng ngh thng tin, nng cao kh nng phc v ca h thng. Nhng nng cp nh th no li l mt bi ton nan gii. Doanh nghip c th chn phng n d dng l xut trang b mi nhiu thit b phn cng c hiu nng mnh (my ch c b vi x l tc cao, thit b chuyn mch tc cao, cc t a lu tr c dung lng ln...). Xu hng thc t l cc thit b phn cng vi nhng tnh nng ci tin, hiu nng mnh xut hin ngy cng nhiu trn th trng v gi thnh c chiu hng ngy cng r hn, d chp nhn hn. Tuy nhin, ngay c vi thc t , vic thng qua mt gii php nh vy cng cn nhiu iu phi suy xt. V i cng vi nhng thit b mi s l s pht sinh cng vic v s phc tp v tch hp h thng, v bo m bo mt thng tin, bo tr v vn hnh. Hn na, doanh nghip khng th ch tnh ton nhng nhu cu hin ti, m cn phi d tr nhng nhu cu tng lai. Thng th nhng thit b vi cu hnh cao hn nhu cu hin ti s c chn, nhm m bo cho h thng c th duy tr c mt thi gian di trc khi li phi nng cp mt ln na. Nhng la chn em li kh nng m rng thng i vi mt chi ph cao. Doanh nghip phi chn mt gii php cn i gia chi ph v kh nng m rng. Thm ch, c doanh nghip cn c nhu cu v mt gii php c th p ng linh hot nhu cu s dng. Ngha l khng ch kh nng m rng, v cn c kh nng thu hp quy m h thng tit kim chi phi, p ng nhng thay i nht thi. i vi cc nh cung cp c s h tng cng ngh thng tin, nhu cu t ra l phi phc v c nhiu h thng my ch ca cc doanh nghip khc nhau nhng ng thi vn m bo nhu cu v ti nguyn cho php. Ti nguyn phi

c s dng hiu qu, trnh cc my ch nhn ri, va tit kim c chi ph vn hnh, va nng cao nng lc phc v ca h thng my ch. Cn c cc bin php cn bng ti lm c iu . M hnh cho thu phn cng vt l nh trc y khng t c s linh hot cn thit, thay vo phi l mt gii php khc hiu qu hn. Vi yu cu v thc trng nh vy, ngy nay hu ht doanh nghip la chn cc cng ngh o ha cho vic xy dng, nng cp c s h tng cng ngh thng tin ca mnh. o ha, cng vi in ton m my, l li gii cho nhng vn tng lm au u khng t nh qun l doanh nghip, v cng l gii php hiu qu cho bi ton ca cc nh cung cp dch v. Khng phi ngu nhin m cng ty nghin cu v t vn trong lnh vc cng ngh thng tin c uy tn l Gartner nh gi rng o ha l mt trong 10 hng cng ngh nng nht ca nm 2008. V nu chng ta cng theo di nhng tin trin, kt qu v cng ngh v ng thi u t, qung b thc y cc gii php o ha t cc hng ln nh Intel, IBM, HP, Cisco trong thi gian qua, th nhn nh ca Gartner l hon ton c c s.

1. Tng quan1.1. Khi nim o hao ha (virtualization), theo ng ngha ca t ny, l lm cho mt s vt c bn cht A dng nh tr thnh mt s vt khc c bn cht B t gc nhn ca ngi s dng. Ni cch khc, ngi s dng ch bit n v ch nhn thy bn cht B ca s vt, i vi h bn cht A c o ha thnh bn cht B. o ha trong in ton, l vic to ra mt phin bn o (mt phin bn ch tn ti v mt logic) ca mt thc th nh nn tng phn cng, h iu hnh, h thng lu tr, hoc ti nguyn mng. o ha c xem nh l mt phn ca xu hng chung i vi cc h thng thng tin cho doanh nghip, xu hng bao gm c c in ton t tr (autonomic computing), mt kch bn m trong mi trng in ton c th t qun l da trn nhng thng tin theo di c t hot ng ca chnh n, v in ton theo yu cu (utility computing), khi m nng lc x l ca my tnh c xem nh l tin ch m khch hng c th chi tr theo nhu cu s dng. Trong c hai xu hng, vai tr ca o ha cng l rt quan trng. Ban u cng ngh o ha c nghin cu vi mc ch m phng v kim th. Nhng v sau ny, mc tiu chnh m o ha nhm n l mi trng phn tn, vi bi ton qun l v cn bng ti cho h thng. Nhng li ch khc c th k n l gip to ra s c lp gia h thng v nn tng phn cng, to ra cc lp tng thch, cc ng dng a nn (cross platform).

1.2. Phn loi o ha

o ha mng (Network virtualization) l vic gom cc ti nguyn phn cng, phn mm v cc chc nng mng thnh mt thc th n l, c kh nng qun l da trn phn mm (c gi l mng o - virtual network). Thnh phn chnh ca mng o l nhng ng kt ni o v cc knh o. Cc ng dng v dch v s c gn cung cp trn cc knh c th theo yu cu s dng (assign for request).

o ha phn cng (Hardware virtualization) hay o ha h thng (system virtualization) l vic to ra cc my o hot ng nh mt mt tng trung gian gia h thng phn cng my tnh v phn mm chy trn n. Cc kin trc o ha che giu cc c tnh vt l ca cc ngun ti nguyn my tnh, v khin chng tr nn c lp vi cc h thng bn trn, bin ti nguyn my tnh vi vai tr l mt khi nim vt l thnh ti nguyn logic. Nh c o ha, nhiu h iu hnh c th chy cng thi im trn cng mt my tnh hay thm ch h iu hnh c th coi mt nhm my tnh vt l ch l mt ngun ti nguyn n l. o ha my ch (server virtualization) l ti ch yu khi cp n o ha phn cng, khi m h thng phn cng y ng vai tr l my ch.

o ha phn mm (Software virtualization), m thng gp l trng hp o ha ng dng (Application virtualization), khi m mt ng dng c cung cp n ngi dng m khng cn phi ci t hon chnh trn my khch. Thay vo khi c gi, ng dng mi c ti v lu tr cc b ti cc my khch v chy trn lp m l mi trng o ha nm ngay trn h iu hnh. Mc tiu ca o ha ng dng chnh v cung cp cc lp tng thch (compatibility layers), gip tch ri s ph thuc gia h iu hnh v ng dng vi nhau, ng thi gim thiu xung t phn mm. Mt ng dng khc ca o ha phn mm l o ha h iu hnh (OS-level virtualization), s c cp sau.

o ha h thng lu tr (Storage virtualization) v c bn l s mphng, gi lp vic lu tr t cc thit b lu tr vt l. Ngi dng hoc ng dng truy cp vo khng cn quan tm n mnh truy cp vo thit b lu tr

vt l no, u, nh th no. V d mt a vt l dung lng ln c th c phn thnh nhiu a logic cho mi ngi dng, hay nhiu a vt l c th c gp li trong mt giao din lu tr duy nht i vi ngi dng cui.

1.3. o ha my cho ha my ch l cng ngh ng dng o ha nhm khai thc trit kh nng lm vic ca cc phn cng trong mt h thng my ch. tng ca o ha my ch l to ra nhiu my ch o trn mt my ch vt l, mi mt my o cng c cp pht ti nguyn phn cng nh my tht vi RAM, CPU, card mng, cng, h iu hnh v cc ng dng ring.

o ha my ch mang li c hi ct gim chi ph bng vic gim s lng my tnh. t my tnh hn ngha l cn t din tch hn, t nhn vin hn v tiu th in nng hng ngy gim i. Ngoi ra, o ha cng ha hn to ra kh nng in ton vi hiu qu cao hn. o ha chnh l cha kha cnh ca in ton m my (cloud computing). Mc d khng phi l bt buc, nhng nhng m hnh m my s dng cng ngh o ha s c hiu nng v tnh linh hot cao hn nh kh nng chia s cc ti nguyn o thng qua h thng mng. Thc ra, chia s ti nguyn khng phi l ci g mi m, nhng bng cch s dng o ha, chi ph trin khai h thng

s c gim ng k v bn cnh cn m bo c tnh hiu qu trong vic s dng cc ti nguyn. Cc li ch ca o ha my ch. Nhng li ch c th k n ca o ha my ch:

Qun l n gin: khi trin khai h thng o ho th s lng my ch vt l gim i ng k v khi vic theo di v gim st h thng rt d dng v hu nh c thc hin bi cng c phn mm qun tr tp trung. Vic qun tr c th t xa do nh cung cp dch v m my h tr.

Trin khai nhanh: thay v ci t my ch, ch cn khi phc mt bn sao lu hoc n gin l sao chp tp tin my o trong phn mm o ha. i vi nhiu my ch, vic trin khai hng lot mt cch t ng l iu c th. Vic nng cp phn cng c thc hin nhanh chng v n gin bng cc th tc phn mm.

Tng kh nng chu li v khi phc sau thm ha: vic o ha c lp phn ln cc li ca my ch o khi my vt l. Ngoi ra nu mt my vt l b s c th cc my o s c di chuyn nng n my ch khc v c th hot ng li ngay tc th. Sao lu v khi phc d dng, hon ton bng phn mm.

Cn bng ti v phn phi ti nguyn linh hot: vi cc cng c qun l t xa cc my ch v my o ta s thy c tnh trng ca ton b h thng t c chnh sch nng cp my vt l hoc my o hoc di chuyn my o ang qu ti sang my ch vt l c cu hnh mnh hn, c nhiu ti nguyn cn trng hn hot ng. iu ny gip i ph c vi nhng yu cu ti nguyn tng mt cch t bin trong thi gian ngn, nh ti nguyn vt l c tn dng ti a. Nhng my ch thng xuyn trao i thng tin vi nhau c th c di chuyn n nhng v tr vt l gn nhau hn tng cng hiu nng (collocation).

Tit kim: Thng thng, cc server ch s dng rt t ti nguyn ca h thng, trong phn ln l b vi x l v b nh. Cc nghin cu cho thy trung bnh doanh nghip ch s dng khong 5 n 25% cng sut my ch. iu cng c ngha l chng ta ang lng ph ti nguyn v tng chi ph cho nhng g m ta khng cn, y l chi ph lm mt, chi ph chy duy tr

h thng, chi ph tr cho nhn vin vn hnh o ha c ngha l t my ch hn, ng ngha vi vic cc chi ph lin quan n vic vn hnh my ch u gim xung. C s h tng nh mt dch v (Infrastructure as a Service - IaaS)

Dch v h tng (IaaS) l mt dng ca in ton m my nhm cung cp cho ngui dng h tng th (my ch, h thng lu tr, h thng mng) di dng cho thu. Khi nim ny do nh kinh t hc Nichlas Car xng vo thng 3 nm 2006. Ban u n c tn gi l dch v phn cng (Hardware as a service - HaaS), nhng t ny d dn b thay th bi dch v h tng vo khong cui nm 2006. Nhng v d ca dch v dng ny c th k n l Amazon EC2/S3, Elastra, Nirvanix, AppNexus Cng ngh o ha ang m ra nhiu trin vng cho dch v h tng pht trin, nh m hnh mng o (virtual network) hay ang cp n trong bi tiu lun ny l my ch o (virtual server). i vi a s doanh nghip va v nh th vic thu my ch o kinh t hn hn thu mt my ch vt l, v cng hn vic u t mua sm phn cng. Trn thc t l cc m hnh IaaS ngy nay u cung cp dch v bng vic cung cp cc my ch o. Nhng dch v IaaS thng c tnh ph trn c s tnh ton chc nng v lung ti nguyn s dng, tip cn n m hnh thu bao dng bao nhiu tr by nhiu nh trong cc ngnh vin thng, in lc...

Nhng c trng tiu biu: Cung cp ti nguyn nh l dch v: bao gm c my ch, thit b mng, b nh, CPU, khng gian a cng, trang thit b trung tm d liu. Kh nng m rng linh hot: chi ph thay i ty theo thc t, nh cng ngh o ha, nhiu ngui thu c th cng dng chung mt ti nguyn vt l. Cc cp trin khai h thng my ch o Mt d n o ha thnh cng l d n t c mc t ng ha cao trong vic qun l v iu phi cc ti nguyn ca c s h tng cng ngh thng tin. Mc t ng ha th hin cp trin khai h thng my ch o. Cc cp ny, cng c th xem nh mt l trnh tng bc m doanh nghip mun o ha c s h tng cng ngh thng tin c th tham kho. Trong cun Enterprise Cloud Computing: Technology, Architecture, Applications ca Gautam Shroff chia lm 4 cp :Cp 1 Virtual images (nh h thng): ng gi mi trng chun

cho nhng loi ng dng khc nhau thnh cc my o, nh lm gim thi gian ci t, trin khai cng nh kim th h thng. mc ny, doanh nghip s gim c nhiu chi ph qun l v thi gian pht trin h thng.Cp 2 Integrated provisioning (tch hp): cc my o c cp

pht da trn s chn la my vt l thng qua mt giao din qun l duy nht. Cc cng c nh Virtual Center ca VMware h tr nhng thao tc ny. Tuy nhin, n nay mi ch mt s doanh nghip trin khai thnh cng o ha mc ny trn quy m ln.Cp 3 Elastic provisioning (cung cp co gin): t ng quyt nh

my vt l no s c s dng da trn yu cu ti nguyn ca my o, theo l kh nng to ra cc my ch o m khng cn s can thip ca qun tr vin.Cp 4 Elastic operations (vn hnh co gin): t ng cp pht cc

my ch o v di tr (migrating) nhng my o ang chy da trn nhu

cu phn b ti nguyn, c thit lp thng qua vic t ng gim st tnh trng s dng ti nguyn ca cc my o. Nhng cng ngh nh Vmotion ca VMware cho php thc hin vic di chuyn nng cc my o ngay khi n ang hot ng (in-ight), nh c nhng cng ngh nh vy m vin cnh ca cp 4 tr nn gn hn i vi cc doanh nghip. Cc d n o ha ca doanh nghip hin nay mi ch t n cp 1 v 2. t c cp 3 ch c nn tng m my Amazon EC2 s dng cng ngh o ha ca Xen. Tip cn n cp 4 c th ni l rt t d n, v ch c th t n tm c nhng doanh nghip cung cp dch v m my. Vic a vo vn hnh mt h thng nh vy quy m ln cho n nay cha d n no lm c. Thm ch trong mt nn tng m my nh EC2, c kh nng t ng co gin (monitoring and auto-scaling facilities), th vic kt hp n vi kh nng di chuyn nng cc my o (in-ight migration) vn cha c p dng.

2. M hnh hot ng2.1. Cc mc o ha my chTy theo tng sn phm o ha c trin khai (nh VMware, Microsoft HyperV, Citrix XEN Server) m mc o ha c th s khc nhau. OS-level virtualization (o ha h iu hnh) o ha h iu hnh l mt dng o ha phn mm khi m h iu hnh cho php nhiu th hin ca khng gian ngi dng khc nhau c th cng chy. Nhng th hin chnh l nhng OS o (cn gi l container, VE, VPS hoc jail ty trng hp s dng) em n cho ng dng v ngi dng cm gic nh mt my ch tht. Nhn ca h iu hnh cung cp tnh nng qun l ti nguyn cho php c lp cc container, nhm trch xung t ti nguyn vi nhau. Chi ph thc hin o ha h iu hnh tng i thp, vi hiu nng h thng cao, v cc ng dng trong container ch n gin chy v gi nhng li gi h thng nh bnh thng, khng cn phi c mt b gi lp hoc my o trung gian. Gii php ny cng khng i hi s h tr t phn cng. Tuy nhin nhc im ln nht ca o ha h iu hnh l km linh hot, bi h iu hnh khch cng chnh l h iu hnh ch (hoc c chung nhn nh nhn linux) do , o ha h iu hnh ch thch hp vi cu hnh thun nht. V l do ny nn o ha h iu hnh l mt phng php l tng cho cc cng ty my ch web hoc cc mi trng host o (virtual hosting), v hu ht cc web server kh tnh v khng ci nhiu phn mm. o ha h iu hnh cng c dng, nhng t hn, hp nht nhiu my ch vt l li bng cch chuyn dch v t nhiu host v mt container duy nht.

Hnh H3.1.1: OS-level virtualization Full virtualization (gi lp phn cng) L khi m my o l mtnh ca ton b h thng, bao gm BIOS o, khng gian b nh o, v cc thit b o. H iu hnh khch (cc h iu hnh ci trn my ch o) khng b thay i, v chng hot ng nh trn phn cng tht s. Full virtualization ch yu da trn vic gi lp phn cng my tnh. Mc d cc h thng gi lp ni chung u khng c hiu nng cao nhng cng ngh ny cng ci thin c rt nhiu nh s h tr ca cc nh sn xut phn cng. Cc cng ty cung cp phn mm o ha m phng phn cng gm c VMware ( c hai phin bn VMware Server v ESX Server) v Microsoft.

Hnh H3.1.2: Full virtualization Paravirtualization (o ha song song) Vi phng php o ha ny, thay v m phng mt mi trng phn cng hon chnh, phn mm o ha ch m phng mt phn, v cung cp cc dch v h iu hnh khch tng tc vi phn cng. Paravirtualization em li tc cao hn so vi full virtualization.

Hnh H3.1.3: Paravirtualization

Paravirtualization c hai u im. Th nht, hiu nng h thng cao hn do khng cn m phnghon ton phn cng vt l. Th hai l n khng gii hn cc trnh iu khin thit b trong phn mm o ha, thc t l paravirtualization khng h c cc trnh iu khin thit b. Thay vo , n s dng cc trnh iu khin thit b c trong h iu hnh ch, tn dng c nhiu loi phn cng, ch khng b gii hn nhng thit b m cc trnh iu khin phi sn c trong phn mm o ha nh trong o ha m phng phn cng. Tuy nhin, phng php o ha ny cng c mt nhc im ln, c th s dng cc dch v ca h iu hnh ch, cc h iu hnh khch phi c tinh chnh. Do h iu hnh khch chy o ha song song khng phi l phin bn gc ging ht nh my tht. iu ny c ngha l khng phi bt c h iu hnh no cng c th chy Paravirtualization c (tri vi Full Virtualization).

XP Mode caWindows 7 l mt v d in hnh v Paravirtualization. Mt v d khc l sn phm ngun m vi tn gi Xen, xut hin trong cc b n phn phi Linux gn y t Red Hat v Novell, v c trong nhiu ngun phn phi cng ng Linux nh Debian v Ubuntu. Ngoi ra cn c Virtual Iron, mt phn mm tim nng da trn Xen.

2.2. Kin trc ca mt h thng o haHypervisor Hypervisor hay cn gi l virtual machine monitor (VMM), l mt lp phn mm gia phn cng v h iu hnh cp pht v cho php cc h iu hnh qun l v s dng ti nguyn phn cng o. Ty theo vai tr ca hypervisor trong kin trc h thng, cc m hnh o ha c th hai dng hosted hypervisor (cn gi l host-based) hoc bare-metal hypervisor (cn gi l hypervisor-based). Hosted hypervisor L mt kin trc o ha m trong hypervisor chy trn mt h iu hnh ch khc. Ngha l tng tc vi ti nguyn phn cng n phi lin lc thng qua h iu hnh ch. Cc sn phm in hnh cho kiu o ha ny l VMware Server, Microsoft Virtual PC, my o Java.

Hnh H3.2.2: Hosted hypervisor

Mt s h thng hypervisor dng Hosted c th k n nh VMware Server, VMware Workstation, Microsoft Virtual Server Mt h thng o ha s dng kin trc Host-based c chia lm 4 lp hot ng nh sau:

Nn tng phn cng: Bao gm cc thit b nhp xut, thit b lu tr(Hdd, Ram), b vi x l CPU, v cc thit b khc (cc thit b mng, vi x l ha, m thanh)

H iu hnh ch (host operating system): H iu hnh ny thchin vic lin lc trc tip vi phn cng, qua cung cp cc dch v v chc nng thng qua h iu hnh ny.

Virtual Machine Monitor: chy trn h iu hnh ch, ly ti nguyn vdch v do h iu hnh ch cung cp, thc hin vic qun l, phn chia trn cc ti nguyn ny.

Cc my o: s dng ti nguyn do hypervisor qun l, cc h iu hnhkhch (guest operating system) chy trn nn cc my o ny. Bare-metal hypervisor

Hnh H3.2.3: Bare-metal hypervisor Hypervisor hot ng nh l mt lp phn mm nm ngay trn phn cng. Mc ch chnh ca n l cung cp cc mi trng lm vic cho cc my o. Cho php cc my o hot ng trn mt phn ca phn cng c gi l phn vng (partition). Cc h iu hnh ca my o c ci t trn phn vng ny.

Mi phn vng s c cung cp tp hp cc ti nguyn phn cng ring ca n chng hn nh b nh, cc chu k CPU v thit b. Hypervisor c trch nhim iu khin v phn phi cc lung truy cp n cc ti nguyn phn cng. Trong m hnh ny trnh iu khin phn cng lin lc trc tip vi cc thit b phn cng m khng phi qua bt k trung gian no nn n mang li mt hiu sut cao nht v s dng ti nguyn phn cng. Ta c th thy, mt h thng o ha my ch s dng nn tng bare-metal hypervisor bao gm 3 lp chnh:

Nn tng phn cng: Bao gm cc thit b nhp xut, thit b lu tr(HDD, RAM), b vi x l CPU, v cc thit b khc (cc thit b mng, vi x l ha, m thanh)

Virtual Machine Monitor: thc hin vic lin lc trc tip vi nn tngphn cng pha di, qun l v phn phi ti nguyn cho cc h iu hnh khc nm trn n.

Cc my o: ly ti nguyn t phn cng, thng qua s cp pht v qun lca hypervisor. Bare-metal hypervisor li chia lm hai dng l Monolithic Hypervisor v Microkernelized Hypervisor

Hnh H3.2.3.2: Kin trc nguyn khi v kin trc vi nhn

Monolithic Hypervisor (kin trc nguyn khi). L kin trc m hypervisor cha tt c trnh iu khin thit b. Khi cc h

iu hnh chy trn cc my o truy cp phn cng th s thng qua lp trnh iu khin thit b ca lp hypervisor. V d cho m hnh ny chnh l VMware ESX Server. M hnh ny c nhc im l my o b l thuc vo trnh iu khin thit b phn cng ca hypervisor, nu n b h hng hay xut hin li th cc my o u b nh hng v nguy hi. Thm vo l th trng phn cng ngy nay rt a dng nn trnh iu khin ca Hypervisor trong loi o ha ny c th s khng th h tr iu khin hot ng ca phn cng ny mt cch ng n v hiu sut chc chn cng s khng c ti u. Vic ph thuc qu nhiu vo cc loi thit b dn ti s hn ch pht trin cng ngh ny. Microkernelized Hypervisor (kin trc vi nhn) Trong cc my o Microkernelized Hypervisor nh cng ngh Hyper-V, trnh iu thit b c y ln lp my o bn trn. Khi my o c nhu cu truy nhp phn cng th trnh iu khin ca n s lin lc trc tip vi phn cng thng qua mt knh tc cao c hypervisor to ra. Mt s v d v cc h thng Bare-metal hypervisor khc nh l: Kernelbased Virtual Machine (KVM), Oracle VM, IBM's POWER Hypervisor (PowerVM), Citrix XenServer Hybrid Hybrid l mt kiu o ha mi hn v c nhiu u im. Trong lp o ha hypervisor chy song song vi h iu hnh ch. Hybrid thng c hiu nhm l dng kin trc o ha th 3. Tuy nhin trn thc t n ch l 1 dng ca hosted hypervisor, trong cu trc o ha ny cc my ch o vn phi i qua h iu hnh ch truy cp phn cng. Khc bit l ch c h iu hnh ch v cc my o u chy trong ch nhn (kernel mode, thay v ch ngi dng (chy nh mt ng dng ci trn h iu hnh). Mc ch chnh ca kin trc hybrid l gip tng hiu nng ca my o.

o ha Hybird c s dng trong hai sn phm o ha ph bin ca Microsoft l Virtual PC 2007 v Microsoft Virtual Server 2005 R2.

3. Thay cho li ktS pht trin ca in ton m my trong vng 15 nm tr li y mang n nhng c hi tt cho thng mi in t trong bi cnh kinh t suy thoi, cho php trao i thng tin nhanh chng hn, thc y ci tin cng ngh, gim thiu chi ph. Nh cc dch v m my, doanh nghip s khng cn phi c c s h tng ni b m vn c th trin khai nhanh chng cc dch v, vi lng ti nguyn s dng ln, khng cn ti b my nhn s cng knh hoc mc chuyn gia, tr thu bao v c th d dng thay i qui m khi cn thit. Nhng bt kp xu th , mt tt yu phi tun theo chnh l o ha c s h tng thng tin ca cc doanh nghip. Vi cng ngh o ha my ch, doanh nghip s qun l ngun ti nguyn cng ngh thng tin hiu qu hn, v sn sng hn trong vic a cc my ch ca mnh ln my. i vi cc nh cung cp, o ha my ch m ra mt loi hnh dch v mi: dch v h tng. o ha my ch to ra mt m hnh cho thu (outsource) c s h tng cng ngh thng tin hiu qu. Nhng chi ph d tha ca vic s hu nhng h thng my ch, trung tm d liu ln ca tng doanh nghip n l s b loi b. Thay vo l vic chuyn mn ha, ti u chi ph v cht lng h tng cng ngh thng tin chung cho nhiu t chc, c nhn, doanh nghip, hng ti cung cp c s h tng cng ngh thng tin nh mt dch v vi gi thnh phi chng m nhiu i tng c th tip cn c. Mc d cng ngh o ha vn cn li nhng thch thc nht nh, nh nhng thch thc t cng ngh ( nu trn), hay nhng thch thc n t con ngi, t khu qun l, nhng nhng li ch m n mang li ng doanh nghip ln k hoch ngay t by gi.