The paper presents the architectural solutions and the experimental results of the integration of two networks, a Campus terrestrial Network and a Geographic satellite Network, which have been designed and deployed by the CNIT (Italian National Consortium for Telecommunications). The two networks were developed in different contexts and use a different approach, but they have the common aim to demonstrate the feasibility of a tele-teaching system using standard and ad-hoc software application. The result of the integration is a nation-wide distributed tele-education network with a large number of clients. It is composed of an ATM/ADSL network within a Campus and of a TCP/IP satellite network, which acts as a backbone for the geographic distribution. On one hand, the ATM portion of the network allows reserving specific network resources for each flow (even if it is not necessary in the experiment performed due to the high capacity available), on the other hand, through a satellite network, whose bandwidth is limited to 2 Mbits/s, a TCP/IP suite is used. TCP/IP protocols offer a best-effort service but, in this case, a guaranteed service should be offered. There are two methods in the literature to reserve resources in a TCP/IP-based network: the Integrated Services and the Differentiated Services. The former has been chosen in this environment, on the base of previous experimental studies and of the test-bed dimension. The experiment of integration has been investigated by using both subjective and objective performance parameters. Network users (students) have been asked to fill in reports to measure the Perceived Quality of Service, in order to get a Mean Opinion Score (MOS) about the level of user perception of the overall tele-teaching service. Measurements of packet loss and jitter have been also performed in order to assess the Quality of Service of the integrated network.
A Tele-Education Oriented Experiment based on an Integrated Terrestrial/Satellite Network / Adami, D; Castoldi, P; Marchese, M; Morelli, A; Ronga, L. - (2001), pp. 1-5. (Intervento presentato al convegno 7th Ka band Conference tenutosi a S. Margherita Ligure (GE) nel Sept. 2001).
A Tele-Education Oriented Experiment based on an Integrated Terrestrial/Satellite Network
CASTOLDI P;MORELLI A;
2001-01-01
Abstract
The paper presents the architectural solutions and the experimental results of the integration of two networks, a Campus terrestrial Network and a Geographic satellite Network, which have been designed and deployed by the CNIT (Italian National Consortium for Telecommunications). The two networks were developed in different contexts and use a different approach, but they have the common aim to demonstrate the feasibility of a tele-teaching system using standard and ad-hoc software application. The result of the integration is a nation-wide distributed tele-education network with a large number of clients. It is composed of an ATM/ADSL network within a Campus and of a TCP/IP satellite network, which acts as a backbone for the geographic distribution. On one hand, the ATM portion of the network allows reserving specific network resources for each flow (even if it is not necessary in the experiment performed due to the high capacity available), on the other hand, through a satellite network, whose bandwidth is limited to 2 Mbits/s, a TCP/IP suite is used. TCP/IP protocols offer a best-effort service but, in this case, a guaranteed service should be offered. There are two methods in the literature to reserve resources in a TCP/IP-based network: the Integrated Services and the Differentiated Services. The former has been chosen in this environment, on the base of previous experimental studies and of the test-bed dimension. The experiment of integration has been investigated by using both subjective and objective performance parameters. Network users (students) have been asked to fill in reports to measure the Perceived Quality of Service, in order to get a Mean Opinion Score (MOS) about the level of user perception of the overall tele-teaching service. Measurements of packet loss and jitter have been also performed in order to assess the Quality of Service of the integrated network.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
