dc.description.abstract | Network services are more and more popular, and every Internet Service Provider (ISP) begins to offer all kinds of network services, including Voice over IP (VoIP), video conference and so on. In order to receive the normal service, these services must meet Quality of Service (QoS) requirements demanded by customers. To define normal services, the customers will sign Service Level Agreements (SLA) with ISPs to ensure ISP can reach QoS, which customers demand. Because the customers may use the network services in different ISPs, network managers are not able to know network service status across network domains, and the right of the customers is ignored.
This thesis proposes a P2P-based QoS Monitoring System (QMS). It considers the customers view, gathers a large number of users that distributed in the network, and makes comprehensive network connection service monitoring, so that common customers can use this system to determine whether its network meets SLA signed with the ISP, and guarantees customers’’ right. The proposed system uses P2P architecture to improve flexibility and robustness. Even if a user leaves this system, another user at the same network domain can replace to maintain QoS information of monitoring continuously. In addition, the feature of the P2P architecture that users are distributed everywhere is used to increase the range of QoS monitoring and ISPs need not to change configurations of network devices. Every monitored destination uses 2696.536 bps, it is enough for ADSL. The proposed system can avoid problem that user cannot get QoS information because ISPs block packets from some domains in using firewall or network device configuration. The proposed system can get QoS information from other nodes. This system is divided into the two kinds of roles, One is the Monitor Agent, which is installed in customers’ computers, and monitors each other to get network connection information between two Monitor Agents; Another is the Monitor Information Collector, which collects network connection information form the Monitor Agent and provides information to all customers who install this system. | en_US |