Angel V.  Nikolov, 
    Analytical Model for Performance Evaluation of an Asynchronous Web Server,
    Asian Journal of Information Technology,
    Volume 13,Issue 3,
    2014,
    Pages 126-130,
    ISSN 1682-3915,
    ajit.2014.126.130,
    (https://makhillpublications.co/view-article.php?doi=ajit.2014.126.130)
    Abstract: This study deals with analytical performance evaluation of 
  asynchronous web server. The queuing model of the server consists of merge configuration 
  of multiple servers and splitting configuration of single servers in tandem. 
  A set of few equations is presented solution of which produces performance metrics 
  including the occupancy probabilities of all servers. Numerical results show 
  significant improvement of the performance as the number of the multiserver’s 
  units increases.
    Keywords: Asynchronous web server;merging;splitting;BAS;tandem