As SNMP management system has some weaknesses due to its built-in functional limitation, NETCONF, with XML as its data encoding scheme, is viewed as a promising solution for future network configuration management. To make NETCONF interoperable and capable of manipulating data in a standardized fashion, an extensible data modeling language, YANG, was proposed to model data including configuration and state data manipulated by NETCONF protocol, remote procedure calls and notifications. To make YANG understood better, we have done some comparison between YANG and others like XSD and RelaxNG both from theory and practice. The investigation is performed by modeling four models respectively using YANG,XSD and Relax NG, including NETCONF Monitoring, Accessing Control List, VLAN and TCP/IP Monitoring. The experimental data is compared and explained detailedly in the paper combining theoretical analysis. As a result, we concluded that YANG is a better option of modeling language for NETCONF protocol.