Abstract: In this paper the classification of the most used load balancing methods in distributed systems (including cloud technology, cluster systems, grid systems) is described. Load balancing is represented on four levels of network model OSI: channel, network, transport, application. Features, advantages and shortcomings are presented for each level. Also strengths and weaknesses of network, transport and application levels are described. Basics of hardware based load balancing in Network Packet Broker and Application Delivery Controllers, that working on OSI layers 2-7, are described. In this work strengths and weaknesses of hardware based load balancing are shown. Basics of software based load balancing are carried out. Differences between software based load balancing and hardware based one are described too. In the work characterizations of the most used dynamic load balancing algorithms in distributed systems is described. Advantages and shortcomings of each algorithm are carried out. Load balancing uses a variety of methods and algorithms for balancing. In the work methods that are used on channel, network, transport, application levels of OSI model and available in balancers and/or can be configured on the servers are presented and analyzed. Employment, effectiveness, strengths and weaknesses of each type of the methods are described in accordance with analysis. Following methods are carried out: direct Routing, Network Address Translation, Source Network Address Translation, Transparent SNAT, SSL Termination or Acceleration, TCP/IP server load balancing, Hashing, Caching, DNS load balancing, Network Load Balancing, Proxy method, Load balancing by using redirection.

Keywords: Keywords— load balancing, distributed system, hardware and software load balancing cloud, DNS, network level, Network Address Translation, proxy.

ACM Classification Keywords: C.2.0 General – Open Systems Interconnection reference model (OSI), C.2.3 Network Operations - Network management, C.2.4 Distributed Systems - Client/server, Distributed applications

Link:

METHODS AND ALGORITHMS OF LOAD BALANCING

Igor Ivanisenko

http://www.foibg.com/ijitk/ijitk-vol09/ijitk09-04-p04.pdf