Virtual Machine Migration based on Trust Measurement of Computer Node

Transcription

1 Appled Mechancs and Materals Onlne: ISSN: , Vols , pp do: / Trans Tech Publcatons, Swtzerland Vrtual Machne Mgraton based on Trust Measurement of Computer Node Lang Zhhong 1, a, Lang Zhqang 1, b, Tan Ymng 2, c, Lv Xuecheng 2, d, 1 Chna Southern Power Grd Co., Ltd,Guangzhou ,Chna 2 Chna Standard Software Co., Ltd, Shangha ,Chna a langzh@csg.cn, b bbq1018@alyun.com, c ymng.tan@cs2c.com.cn d xuecheng.lv@cs2c.com.cn Keywords: trusted computng, vrtual machne mgraton, trust measurement, load balancng Abstract. Currently, the study of vrtual machne mgraton n cloud computng platform whch usually dd not consder the trustworthness of target physcal machne. For ths, the paper proposes a trusted vrtual machne mgraton wth performance constrants algorthm (TVM 2 PC). The trustworthness of target physcal machne ncludes drect trustworthness and ndrect trustworthness. By ths method, a vrtual machne wll be mgrated to a trusted physcal machne. A large of experment shows that the proposed method can gve a better result than the exstng method n load balancng and trustworthness. Introducton Currently, as a new computng paradgm, cloud computng has the advantages of hgh scalablty and hgh avalablty, whch quckly become a hot topc n academa and ndustry. The vrtualzaton technology s a key technology to realze the capacty of elastc scalablty. In the runnng process of cloud computng, vrtual machne mgraton s what often happens, when the load s mbalance among physcal nodes, or the falure of physcal nodes, or somethng wrong happen. For ths phenomenon, many experts and scholars have proposed varous methods of vrtual machne mgraton. In 2011, Jnjun LIU et al [1] presented a schedulng strategy of vrtual machne mgraton based on load characterstc. Ths strategy ams at the trgger types of nodes and the load characterstcs of vrtual machnes, usng mult-threshold mode to trgger the mgraton, the vrtual machne to be mgrated s selected and the destnaton node s postoned. In 2012, Yong LIU et al [2] proposed an energy-aware and trust-drven vrtual machne schedulng algorthm. The algorthm matched the task and vrtual machne by the trust mechansm between resources and tasks,reached the purpose of ensurng the user task performance and energy-aware n data centers. In 2013, We Huang et al [3] presented a vrtual machne schedulng algorthm based on K-means clusterng.the correlaton of vrtual machne resource allocaton s used as the standard of clusterng,and a vrtual machne s placed on the physcal node complementary to t on resource, so that ts resource s used fully and t s effectve and stable. However, there s also a problem when the vrtual machne mgrates whch s whether the target physcal node s safe and trusted. For an example, when a vrtual machne wll mgrate, although a physcal node s performance meet the needs of the vrtual machne, but ths physcal node has a poor relablty, for example, ths physcal node has a hgh probablty of crash. So ths physcal node wll not be an approprate target node. Therefore, n order to ensure that the target physcal node s trusted. Ths paper presents a vrtual machne mgraton method based on the trust measurement of physcal node. All rghts reserved. No part of contents of ths paper may be reproduced or transmtted n any form or by any means wthout the wrtten permsson of Trans Tech Publcatons, (# , Pennsylvana State Unversty, Unversty Park, USA-15/09/16,20:08:56)

2 Appled Mechancs and Materals Vols Trust Concepts and Computng Method of Trust Accordng to the experts research of trusted computng [4,5], trusted computng descrbes an entty can be trusted f t always behaves n the expected manner for the ntended purpose. A trusted node should have hgh ntegrty, hgh dependablty, hgh avalablty and hgh operatng system (OS) securty level. Defnton 1 (Integrty): Integrty descrbes the degree of physcal node confguraton nformaton, system software, user data and other nformaton has not been tampered or destroyed. The ntegrty of physcal node c s denoted by n (0 n 1). Defnton 2 (Dependablty): Dependablty descrbes the ablty of a physcal node to functon under stated condtons for a specfed perod of tme. The dependablty of physcal node c s denoted by de (0 de 1). Defnton 3 (Avalablty): Avalablty descrbes the proporton of tme a physcal node s n a functonng condton. It s often descrbed as a msson capable rate. Mathematcally, the rato of the total tme a physcal node s capable of beng used durng a gven nterval to the length of the nterval. The avalablty of physcal node c s denoted by av (0 av 1). Defnton 4 (OS securty level): OS securty level descrbes the securty level of physcal node s operatng system (OS). The OS securty level of physcal node c s denoted by se (se {1, 0.75, 0.5, 0.25, 0.1}) [6], the bgger the value, the hgher the OS securty level. Defnton 5 (Drect trustworthness): Drect trustworthness s depended on ntegrty, dependablty, avalablty and OS securty level, the drect trustworthness of physcal node c s denoted by t (0 t 1). In mathematcal sense, drect trustworthness s a functon of ntegrty, dependablty, avalablty and OS securty level, that s t = f (n, de, av, se ). In cloud computng system, f a vrtual machne mgrates from node c to c j, we suppose the node c trusts c j. Smlarly, f a vrtual machne mgrates from node c j to c k, we suppose the node c j trusts c k. So a trust chan (c > c j > c k ) s formed. Usually, n cloud computng system, there are many physcal nodes, and many vrtual machnes have been mgrated n the past perod. So all these trust chans wll form a trust network. Defnton 6 (Trust network): Trust network descrbes the trust relaton between any two physcal nodes, the trust network s drected weghted graph (DWG), trust network s denoted by G=(C, T, E, W). C={c 1, c 2,, c N } s the set of physcal nodes, T ={ t 1, t 2,, t k ) s the set of drect trustworthness of physcal nodes, E={e 1, e 2,, e K }s set of edges, descrbes the trust relaton between two physcal nodes, W={w 1, w 2,, w K ) s the set of edge s weght, descrbes the frequency of vrtual machne mgraton from one node to another. Defnton 7 (In-degree): In trust network, n-degree of a vertex c descrbes the number of edges wth ths vertex c as the termnated vertex. In-degree of vertex c s denoted by d. Defnton 8 (Indrect trustworthness): Indrect trustworthness of physcal node c s depended on the n-degree of c, weghts of ncomng edge whch wth node c as the termnated vertex, and the drect trustworthness of the ncomng edges ntal vertex. Indrect trustworthness s denoted byt (0 t 1). Defnton 9(Comprehensve trustworthness): Comprehensve trustworthness s depended on drect trustworthness and ndrect trustworthness, t s denoted by t (0 t 1). In mathematcal sense, t = f( t, t ). Because the drect trustworthness s depended on ntegrty, dependablty, avalablty and OS securty level, the drect trustworthness of physcal node c can be calculated by the Eq. 1: = α n + α de + α av + se (1) t α2 4 where α = 1. = 1

3 680 Advances n Mechatroncs, Robotcs and Automaton II Because ndrect trustworthness of physcal node c s depended on the n-degree of c ; weghts w k of ncomng edge e k whch wth node c as the termnated vertex, c j as the ntal vertex; and the drect trustworthness t j of the ntal vertex c j. The concept of ndrect trustworthness works by countng the number and qualty of mgraton to a node to determne how trusted the node s. The underlyng assumpton s that more trusted nodes are lkely to receve more vrtual machnes from other nodes. The ndrect trustworthness t of physcal node c can be calculated by the Eq. 2: 1 w j Max{ w j} 2 t = t j [ EXP( )] (2) Vn c j V Max{ w n j} where EXP() represents exponental functon. Accordng to the above analyss, the comprehensve trustworthness s depended on the drect and ndrect trustworthness, the comprehensve trustworthness t of physcal node c can be calculated by the Eq. 3: t = αt + ( 1 α) t (3) Where α denotes trust factor, and 0 α 1. Trusted Vrtual Machne Mgraton Algorthm wth Performance Constrants Accordng to the problem of how vrtual machne mgrates to a trusted physcal node, we desgn a trusted vrtual machne mgraton algorthm wth performance constrants (TVM 2 PC). Although we focus on how to mplement a trusted vrtual machne mgraton, n the actual cloud computng platform, performance and load balancng s stll the most mportant factor that we must consder. So we not only take account of the trustworthness of target physcal node, but also the performance before vrtual machne mgraton. If we only consder the trustworthness of target physcal node, a large number of vrtual machnes may mgrate to a few physcal nodes whch have hgher trustworthness, whch wll result n load mbalance. The man dea of TVM 2 PC s descrbed as follow: Accordng to the load of physcal node, all the physcal nodes are dvded nto three sets C={C lght, C normal, C heavy }, where C lght ={c j 1 j N, 0 l j l lght }, C normal ={c j 1 j N, l lght <l j <l heavy }, C heavy ={c j 1 j N, l heavy l j 1}. Where l j denotes load of physcal node c j, l lght denotes lght load threshold, l heavy denotes heavy load threshold. When a vrtual machne wll mgrate, 1 If C lght, these physcal nodes n C lght have a prorty wth vrtual machne mgraton, and the lghter the load, the hgher the prorty; 2 If C lght = and C normal, these physcal nodes n C normal have a prorty wth vrtual machne mgraton, and the hgher the trustworthness, the hgher the prorty; 3 If C lght =, C normal = and C heavy, these physcal nodes n C heavy wll be consdered when vrtual machnes mgrate, and the lghter the load, the hgher the prorty; The seudo-code of TVM 2 PC s descrbed as follow: L1:for each Mgraton Vrtual Machne vm { L2: for each computer c j C{ L3: l j load(c j ); L4: t j trusted(c j ); L5: } L6: C lght, C normal, C heavy dvde(l 1, l 2,, l N ); L7: f C lght { L8: for each computer c j C lght { L9: l mn= l 1 ; L10: f l j < l mn then L11: l mn = l j ; L12: }

4 Appled Mechancs and Materals Vols L13: return c j ; L14: } L15: else f (C lght = ) (C normal ){ L16: for each computer c j C normal { L17: t max= t 1 ; L18: f t max < t j then L19: t max= t j ; L20: } L21: return c j ; L22: } L23: else f (C lght = ) (C normal = ) (C heavy ){ L24: for all computer c j C heavy { L25: l mn= l 1 ; L26: f l j < l mn then L27: l mn = l j ; L28: } L29: return c j ; L30: } L31: } In order to prove the superorty of the proposed TVM 2 PC algorthm, we desgn another two algorthms, lghtest load prorty (LLP) and hghest trustworthness prorty (HTP). The man dea of LLP s to mgrate the vrtual machne to node of the lghtest load. Smlarly, the man dea of HTP s to mgrate the vrtual machne to the node of hghest trustworthness. Experment Results and Analyss In ths secton we present the smulaton results that show the behavor, regardng vrtual machne mgraton, of three vrtual machne mgraton algorthms that are examned. In the experments, these parameters value s descrbed as follow: the number of physcal nodes N=16; the number of vrtual machnes that need to be mgrated M=1000; the trustworthness of each physcal node t [0, 1], whch s generated randomly; the load of each physcal node l [0, 1], whch s generated randomly; trust factor α=0.6; lght load threshold l lght =0.3; heavy load threshold l heavy =0.8; the dependablty of physcal node de [0.99, 1] and avalablty av [0.99, 1], whch are generated randomly. The experment results are shown n Fg. 1 and 2. Fg. 1 Load of each vrtual machne Fg. 2 The number of addtonal vrtual machne mgraton Fg. 1 presents the load of the 16 nodes for the three vrtual machne mgraton algorthms. Frst of all, we observe that the load of the 16 nodes s mbalance for LLP and HTP algorthms, that s, the curves of LLP and HTP algorthms are dramatc ups and downs. But the curve of TVM 2 PC algorthm s smoother than LLP and HTP.

5 682 Advances n Mechatroncs, Robotcs and Automaton II In the real cloud computng platform, some physcal nodes may crash sometmes. So when a node crashes, all the vrtual machnes, whch are runnng on ths node, need to be mgrated to other nodes. As a result, the crash of physcal nodes wll lead to the addtonal vrtual machne mgraton. Fg. 2 presents the condton of addtonal vrtual machne mgraton for the three vrtual machne mgraton algorthms n fve experments. We observe that the number of addtonal vrtual machne mgraton for HTP algorthm s less than TVM 2 PC and LLP, that s, HTP algorthm s better than TVM 2 PC and LLP n ths regard. LLP algorthm s the worst, but the dfference between TVM 2 PC and HTP s not too many. So, takng nto account the factor of load balancng, TVM 2 PC s a good vrtual machne mgraton algorthm, Conclusons In ths paper, for the problem of vrtual machne mgraton n the cloud computng platform, we desgned a trusted vrtual machne mgraton algorthm wth performance constrants (TVM 2 PC), whch consder the trustworthness and performance when choose a target physcal machne. The algorthm not only acheves the load balancng of cloud computng platform, but also mplements a trusted mgraton, that s, vrtual machne wll be mgrated to a trusted physcal machne. Experment results showed that the proposed method can acheve a better effect n load balancng and trustworthness. Acknowledgements Ths work was fnancally supported by the Natonal Hgh Technology Research and Development Program of Chna (2012AA050212). References [1]J.J. LIU, G.L CHEN, C.X HU. Vrtual machne mgraton schedulng strategy based on load characterstc. Computer Engneerng, 2011, 37 (17): [2]Y. LIU, X.H. WANG, Z. WANG, et al. Energy-aware and trust-drven vrtual machne schedulng. Applcaton Research of Computers, 2012, 29 (7): [3]W. Huang, Z.P. Wen, C, Cheng. Vrtual machne schedulng algorthm based on K-means clusterng n cloud computng. Journal of Nanjng Unversty of Scence and Technology, 2013, 37 (6): [4]Trusted Computng Group (TCG ). TCPA Man Specfcaton, Verson 1.lb [5]C.X. SHEN, H.G. ZHANG, H.M. WANG, et al. Research and development on trusted computng technology. SCIENTIA SINICA Informatons, 2010,40(2): [6]Standardzaton Admnstraton of the Peoples Republc of Chna, GB/T , Informaton securty technology-securty technques requrement for operatng system, Standard Press of Chna, 2006.