IJCNIS Vol. 7, No. 5, 8 Apr. 2015
Cover page and Table of Contents: PDF (size: 515KB)
Web server, embedded system, real-time system, HTTP, Internet of things, Sensing as a service
This paper presents the architecture of embedded real-time web server. Unlike existing web servers, in our approach, requests are processed not in the “first in first out” order but according to their deadlines and the expected server load. For this purpose the Least Laxity First scheduling method is used. First, requests with imposed hard real-time constraints are served. Then requests enclosed by soft deadlines are processed. Finally, request without time requirements are served in the order they arrived. We also present real-time extensions to the Hypertext Transfer Protocol. We propose headers that enable defining hard and soft deadlines, as well as responses containing time information, that are being sent to the client application. The experimental results showed that in case of real-time applications our server misses significantly fewer requests, due to time out, then existing solutions. The presented server may be very useful for implementing real-time services supported by embedded systems, e.g. in future real-time “Internet of things” applications.
Radosław Czarnecki, Stanislaw Deniziak, "Embedded Real-Time HTTP Server", International Journal of Computer Network and Information Security(IJCNIS), vol.7, no.5, pp.1-8, 2015. DOI:10.5815/ijcnis.2015.05.01
[1]Atzoria, L., Iera, A., Morabito, G.: The Internet of Things: A survey. Computer Networks, vol. 54, no.15, pp. 2787-2805 (2010).
[2]H?ller, V. Tsiatsis, C. Mulligan, S. Karnouskos, S. Avesand, D. Boyle: From Machine-to-Machine to the Internet of Things: Introduction to a New Age of Intelligence. Elsevier, 2014.
[3]Xiang Sheng; Jian Tang; Xuejie Xiao; Guoliang Xue, "Sensing as a Service: Challenges, Solutions and Future Directions”, IEEE Sensors Journal, vol.13, no.10, pp.3733-3741, Oct. 2013.
[4]Dargie, W. and Poellabauer, C., "Fundamentals of wireless sensor networks: theory and practice", John Wiley and Sons, 2010.
[5]R. Fielding, J. C. Mogul, H. Frystyk, L. Masinter, P. Leach, T. Berners-Lee, ”Hypertext Transfer Protocol - HTTP/1.1”, IETF, RFC 2616, 1999.
[6]Guinard, D., Trifa, V., Mattern, F., Wilde, E.: From the Internet of Things to the Web of Things: Resource Oriented Architecture and Best Practices. In: Uckelmann, Dieter; Harrison, Mark; Michahelles, Florian (Eds.) Architecting the Internet of Things, Springer-Verlag Berlin Heidelberg (2011).
[7]H. Schulzrinne, A. Rao, R. Lanphier, Real Time Streaming Protocol (RTSP), IETF, RFC 2326,1998
[8]Peter Saint-Andre, Kevin Smith, Remko TronconPeter Saint-Andre, Kevin Smith, Remko Troncon, XMPP: The Definitive Guide, O'Reilly Media, 2009.
[9]Crane, Dave; McCarthy, Phil: Comet and Reverse Ajax: The Next-Generation Ajax 2.0. Apress, (2008).
[10]F. M. Aymerich, G. Fenu, S. Surcis, “A real time financial system based on grid and cloud computing” ACM symposium on Applied Computing, March 2009, New York, pp 1219–1220.
[11]S. Liu, G. Quan, S. Ren, “On-Line Scheduling of Real-Time Services for Cloud Computing” World Congress on Services, July 2010, Miami, pp 459–464.
[12]W. Tsai, Q. Shao, X. Sun, J. Elston, “Real-Time Service-Oriented Cloud Computing” World Congress on Services, July 2010, Miami, pp 473–478.
[13]K. H. Kim, A. Beloglazov, R. Buyya, “Power-aware provisioning of cloud resources for realtime services” International Workshop on Middleware for Grids, Clouds and e-Science, 2009, New York.
[14]K. Kumar, J. Feng, Y. Nimmagadda, Y. Lu, “Resource Allocation for Real-Time Tasks using Cloud Computing” International Conference on Computer Communications and Networks (ICCCN), July 2011, pp. 1-7.
[15]S. B?k, R.Czarnecki, S. Deniziak, "Synthesis of Real-Time Applications for Internet of Things", LNCS vol. 7719, pp. 37-51, 2013.
[16]S. B?k, R. Czarnecki, S. Deniziak "Synthesis of real-time cloud applications for Internet of things" Turkish Journal of Electrical Engineering and Computer Sciences, to be published, http://dx.doi.org/10.3906/elk-1302-178.
[17]Deniziak, S.; Bak, S., "Synthesis of real time distributed applications for cloud computing", Proc of the IEEE Federated Conference on Computer Science and Information Systems (FedCSIS), pp.743-752, 2014.
[18]Embedthis Software, Appweb Architecture, http://appwebserver.org/products/appweb/doc/ref/architecture.html, 2014.
[19]Unicoi Systems, Fusion Embedded? HTTP, http://www.unicoi.com/product_briefs/http.pdf, 2013.
[20]Real Time Logic, Barracuda Web Server, https://realtimelogic.com/products/barracuda-web-server/, 2014.
[21]Duquennoy, S.; Grimaud, G.; Vandewalle, J.-J., "Smews: Smart and Mobile Embedded Web Server", International Conference on Complex, Intelligent and Software Intensive Systems, 2009. CISIS '09, pp.571-576, 2009.
[22]Trotter Cashion, Introducing Chloe - The Realtime Web Server, http://www.trottercashion.com/2011/06/13/intro-ducing-chloe.html, 2011.
[23]S. Loreto, M. Thomson, G. Wilkins, “Hypertext Transfer Protocol (HTTP) Timeouts”, IETF, draft-loreto-http-timeout-00, 2010.
[24]G. C. Buttazzo Hard Real-Time Computing Systems: Predictable Scheduling Algorithms and Applications, Kluwer Academic Publishers, 1997.