求翻译：现今，网络成为了社会必不可少的工具，但网络环境的复杂性、多变性以及信息系统的脆弱性、开放性和易受攻击性，决定了网络安全威胁的客观存在。人们在享受到各种生活便利和沟通便捷的同时，网络安全问题也日渐突出、形势日益严峻。是什么意思？

Today, the network has become an indispensable tool for the community, but the network environment, the complexity, variability and vulnerability of information systems, openness and vulnerability, determine the objective existence of network security threats. People enjoy the convenience of living

At present, the network has become an indispensable tool in society, but the complexity of network environment, variability and the vulnerability of information systems, open, and vulnerability, and decisions of the network security threats exist objectively. It is in the enjoyment of life to facili

Nowadays, the network has become the social essential tool, but the network environment complexity, polytropic as well as the information system vulnerability, openness and vulnerable, have decided the network security threat objective existence.The people while enjoy facilitate and communicate conv

Today, the network became the social essential tools, but the network environment of complexity, variability, and the vulnerability of information systems, openness and ease of attack, determined the objective existence of network security threats. People enjoy the various living facilities and conv

Today, the network became the social essential tools, but the network environment of complexity, variability, and the vulnerability of information systems, openness and ease of attack, determined the objective existence of network security threats. People enjoy the various living facilities and conv