The requirements of network technologies are considered significantly important, because modern enterprises face the trend of e-commerce and widely use the conveniences of Internet communications. Internet Data Center (IDC) provides services to satisfy customers' requirements. Hence, IDC becomes a new area of markets in the world. Due to the market is so small in Taiwan, enterprises cannot get profits, even that they loss business. To alleviate the above problem, we study three frameworks of fundamental services IDC, including infrastructure, superintendence and add-value service. The goal is to find the important services for customer demand by comparing the customer satisfaction between before and after of the rent. We also compare the differences between fundamental factors and service factors, the correlation between integrated service and service factors, and the differences between satisfaction and expecting before and after of the rent. The purpose of our survey is to provide feasible suggestions to IDC managers so that they can not only survive but also get profits. The results have been shown as follows: 1.The important services of customer demand include: (a)power, air-condition, bandwidth fire suppression system under the infrastructure service. (b)anti-virus protection and DOS attacks prevention under the monitoring service. (c)storage backup, remote backup and firewall protection under the add-value service. 2.The high demands for quality of service (QoS) include: (a)power, air-condition, fire suppression system, security access control system and TV security monitoring under the infrastructure service. (b)storage backup remote backup and firewall protection under the add-value service. 3.The unsatisfaction for quality of service include: (a)security access control system, TV security monitoring, temperature & humidity control, and web hosting under infrastructure service. (b)anti-virus protection, DOS attacks prevention under the monitoring service. (c)the cache service under add-value service. 4. We compare the differences between expected QoS and satisfaction. The results are shown in Figure 5.1.2, Figure 5.1.3, and Figure 5.1.4 respectively. 5. We compare the differences between the expected service and satisfaction before and after of the rent. The results are shown that four items are ¡§significant difference¡¨, including (a)air-condition, UPS under the infrastructure. (b)application system hosting, DNS under add-value service. In contrast, six items are no ¡§significant difference¡¨, including (a)security access control and TV security monitoring under infrastructure. (b)server monitoring under the monitoring service, the contracts of various QoS, consultant, systems integration, total solution, remote backup and the whole service. 6. We compare the correlation between the whole service and service factor. The results are shown that six items are ¡§high correlation¡¨, including (a)equipment security under the factor of service demand. (b)equipment security, equipment service, monitoring service under the expected factor for QoS. (c)equipment security and integrated service under the satisfaction factor for QoS.