T. Yakhno (Ed.): ADVIS 2000, LNCS 1909, pp. 147-158, 2000. © Springer-Verlag Berlin Heidelberg 2000 Management of Networks with End-to-End Differentiated Service QoS Capabilities Lisandro Zambenedetti Granville, Rodrigo Uzun Fleischmann, Liane Margarida Rockenbach Tarouco, and Maria Janilce Almeida Federal University of Rio Grande do Sul – UFRGS, Computer Science Institute, Bento Gonçalves Avenue – Block IV Porto Alegre – Rio Grande do Sul, Brazil {granville, uzun, liane, janilce}@inf.ufrgs.br Abstract. Offering QoS on TCP/IP networks is the object of intense research. New applications, such as telemedicine, distance learning, videoconference and others can only be implemented on environments that ensure QoS for the existing services. Usually, routers are the network resources that undergo changes in order to implement it – hosts have little or no influence. This paper presents an implementation of QoS structures offered directly from the host. It also presents a marking process that is run on the end systems and can be remotely managed via SNMP. A signaling application is also described in order to allow QoS requests to inherited applications that do not perceive QoS service on the networks. 1 Introduction The best-effort paradigm currently found on TCP/IP networks is able to offer enough services to support the great number of applications spread on the Internet. However, an important set of applications cannot operate properly on best-effort services only. Applications such as videoconference, distance learning and telemedicine, for instance, will only operate on environments where services are guaranteed. Given this setting, one of the great current challenges is to offer QoS [1] on TCP/IP networks. One of the apparently promising propositions is the use of differentiated services architecture [2] of IETF [3]. Its importance is clear since the Internet2 project [4] has elected differentiated services as the solution for QoS supply. In addition, several manufacturers have supported the solution, and software houses are making support tools available on initial versions (for example, Bandwidth Brokers). The main solution to offer QoS is through network equipment. Currently, hosts perform little or no role in it, leaving the routers with most of the work to be done. On the other hand, chances of success increase with the distribution of QoS tasks. Therefore, it is reasonable to think that involving hosts is also important to run the services properly. This paper presents an implementation of QoS structures based on host implementation. The packet marking process is now run directly on the end systems, separately from the applications. The network manager can program all hosts