A firewall is an approach to security, it helps implement a large security policy that defines the services and access to be permitted. ()

In order to keep competitive in EC, logistics industry has begun to employ the opening, systematical and technical structure. () 点击查看答案&解析

Despite their limitation, however, these systems may eliminateor significantly reducethe costs that companies face when using privately owned electronic networks, making it difficult for smaller companies to afford EDI.() 点击查看答案&解析