It includes requirements as they relate to the signature syntax, data model, format, cryptographic processing, and external requirements and coordination.
它包括涉及签名语法、资料模型、格式、密码处理方面的要求，以及外部要求和协调。
2
It is a first class entity in the meta-model of SimpleRDB, but it has no equivalent in UML 2.0. That is why the signature of the relation has no formal parameter that relates a UML element.
Signature foods: There are many different countries whose traditional ways of eating follow this model, but they all seem to have white rice as a staple.