DocumentCode :
2958300
Title :
Statistical real-time communication over Ethernet for manufacturing automation systems
Author :
Kweon, Seok-Kyu ; Shin, Kang G. ; Zheng, Qin
Author_Institution :
Dept. of Electr. Eng. & Comput. Sci., Michigan Univ., Ann Arbor, MI, USA
fYear :
1999
fDate :
1999
Firstpage :
192
Lastpage :
202
Abstract :
In order to realize real time communication over Ethernet or fast Ethernet, one must be able to bound the medium access time within an acceptable limit. The multiple access nature of an Ethernet makes it impossible to guarantee a deterministic medium access time to individual stations. However one can bound the medium access time statistically by limiting the packet arrival rate at the medium access control (MAC) layer. While focusing on automated manufacturing systems as the main application, the paper considers the connection admission control (CAC) problem for statistically bounding the medium access time of Ethernet. Specifically, a packet is guaranteed to have a medium access time smaller than a predefined bound with a certain probability if the instantaneous packet arrival rate is kept below a certain threshold. Through an analysis, we first derived such a threshold. In order to keep the packet arrival rate under the given threshold, we employ a traffic smoother which: (i) is located between the transport layer and the Ethernet datalink layer and (ii) smooths packet streams between the two layers. The implementation of this traffic smoother requires only a minimal change in the OS kernel without any modification to the current standard of Ethernet MAC protocol or TCP or UDP/IP stack. In order to solve the CAC problem, we derived the probability of transmitting a packet successfully upon each trial by modeling the MAC protocol, 1-persistent CSMA/CD, and the collision resolution protocol, Binary Exponential Backoff, of Ethernet. We implemented a traffic smoother on the Linux OS, demonstrating the effectiveness of our approach in providing real time communication over Ethernet
Keywords :
access protocols; local area networks; manufacturing data processing; operating system kernels; packet switching; probability; real-time systems; telecommunication congestion control; 1-persistent CSMA/CD; Binary Exponential Backoff; CAC problem; Ethernet MAC protocol; Ethernet datalink layer; Linux OS; MAC protocol; OS kernel; TCP; UDP/IP stack; automated manufacturing systems; collision resolution protocol; connection admission control; deterministic medium access time; fast Ethernet; instantaneous packet arrival rate; manufacturing automation systems; medium access control layer; medium access time; packet arrival rate; packet streams; probability; statistical real time communication; traffic smoother; transport layer; Admission control; Ethernet networks; Kernel; Manufacturing systems; Media Access Protocol; Multiaccess communication; Probability; Road accidents; TCPIP; Traffic control;
fLanguage :
English
Publisher :
ieee
Conference_Titel :
Real-Time Technology and Applications Symposium, 1999. Proceedings of the Fifth IEEE
Conference_Location :
Vancouver, BC
ISSN :
1080-1812
Print_ISBN :
0-7695-0194-X
Type :
conf
DOI :
10.1109/RTTAS.1999.777672
Filename :
777672
Link To Document :
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