Experiences with node virtualization for scalable network emulation

During the development of network protocols and distributed applications, their performance has to be analyzed in appropriate environments. Network emulation testbeds provide a synthetic, configurable network environment for comparative performance measurements of real implementations. Realistic scenarios have to consider hundreds of communicating nodes. Common network emulation approaches limit the number of nodes in a scenario to the number of computers in an emulation testbed. To overcome this limitation, we introduce a virtual node concept for network emulation. The key problem for node virtualization is a transparent, yet efficient separation of node resources. In this paper, we provide a brief survey of candidate node virtualization approaches to facilitate scalable network emulation. Based on the gathered insights, we propose a lightweight virtualization solution to achieve maximum scalability and discuss the main points regarding its implementation. We present extensive evaluations that show the scalability and transparency of our approach in both a traditional wired infrastructure-based, and in two wireless ad hoc network emulation scenarios. The measurements indicate that our solution can push the upper limit of emulation scenario sizes by a factor of 10-28. Given our emulation testbed consisting of 64 computers, this translates to possible scenario sizes of up to 1792 nodes. In addition to the evaluation of our virtualization approach, we discuss key concepts for controlling comprehensive emulation scenarios to support scalability of our system as a whole.

[1]  Srinivasan Keshav,et al.  The ENTRAPID protocol development environment , 1999, IEEE INFOCOM '99. Conference on Computer Communications. Proceedings. Eighteenth Annual Joint Conference of the IEEE Computer and Communications Societies. The Future is Now (Cat. No.99CH36320).

[2]  Dejan Kostic,et al.  Scalability and accuracy in a large-scale network emulator , 2002, CCRV.

[3]  Greg J. Regnier,et al.  TCP performance re-visited , 2003, 2003 IEEE International Symposium on Performance Analysis of Systems and Software. ISPASS 2003..

[4]  Mike Hibler,et al.  An integrated experimental environment for distributed systems and networks , 2002, OPSR.

[5]  Miljenko Mikuc,et al.  Operating System Support for Integrated Network Emulation in IMUNES , 2004 .

[6]  Kevin R. Fall,et al.  Network emulation in the VINT/NS simulator , 1999, Proceedings IEEE International Symposium on Computers and Communications (Cat. No.PR00250).

[7]  Luigi Rizzo,et al.  Dummynet: a simple approach to the evaluation of network protocols , 1997, CCRV.

[8]  Kurt Rothermel,et al.  On Node Virtualization for Scalable Network Emulation , 2001 .

[9]  Samuel T. King,et al.  Operating System Support for Virtual Machines , 2003, USENIX Annual Technical Conference, General Track.

[10]  Beng-Hong Lim,et al.  Virtualizing I/O Devices on VMware Workstation's Hosted Virtual Machine Monitor , 2001, USENIX Annual Technical Conference, General Track.

[11]  Jay Lepreau,et al.  Lowering the barrier to wireless and mobile experimentation , 2003, CCRV.

[12]  Kurt Rothermel,et al.  Distributed Emulation of Shared Media Networks , 2003 .

[13]  Christian F. Tschudin,et al.  Coping with communication gray zones in IEEE 802.11b based ad hoc networks , 2002, WOWMOM '02.

[14]  Mostafa H. Ammar,et al.  A generic framework for parallelization of network simulations , 1999, MASCOTS '99. Proceedings of the Seventh International Symposium on Modeling, Analysis and Simulation of Computer and Telecommunication Systems.

[15]  Xuxian Jiang,et al.  vBET: a VM-based emulation testbed , 2003, MoMeTools '03.

[16]  Kurt Rothermel,et al.  A dynamic network scenario emulation tool , 2002, Proceedings. Eleventh International Conference on Computer Communications and Networks.

[17]  Marianne Shaw,et al.  Scale and performance in the Denali isolation kernel , 2002, OSDI '02.

[18]  David A. Maltz,et al.  A performance comparison of multi-hop wireless ad hoc network routing protocols , 1998, MobiCom '98.

[19]  Priya Mahadevan,et al.  MobiNet: a scalable emulation infrastructure for ad hoc and wireless networks , 2005, WiTMeMo '05.

[20]  Dave Maltz,et al.  Emulation of Multi-Hop Wireless Ad Hoc Networks , 2000 .

[21]  Deborah Estrin,et al.  Advances in network simulation , 2000, Computer.

[22]  Carl A. Waldspurger,et al.  Memory resource management in VMware ESX server , 2002, OSDI '02.

[23]  Charles E. Perkins,et al.  Ad-hoc on-demand distance vector routing , 1999, Proceedings WMCSA'99. Second IEEE Workshop on Mobile Computing Systems and Applications.

[24]  Lionel M. Ni,et al.  EMPOWER: a network emulator for wireline and wireless networks , 2003, IEEE INFOCOM 2003. Twenty-second Annual Joint Conference of the IEEE Computer and Communications Societies (IEEE Cat. No.03CH37428).

[25]  Robert N. M. Watson,et al.  Jails: confining the omnipotent root , 2000 .

[26]  Shigeru Chiba,et al.  Secure and manageable virtual private networks for end-users , 2003, 28th Annual IEEE International Conference on Local Computer Networks, 2003. LCN '03. Proceedings..

[27]  Jeff Dike,et al.  A user-mode port of the Linux kernel , 2000, Annual Linux Showcase & Conference.

[28]  Kurt Rothermel,et al.  On the Impact of Radio Propagation Models on MANET Simulation Results , 2005 .

[29]  Mike Hibler,et al.  Feedback-directed Virtualization Techniques for Scalable Network Experimentation , 2004 .