The E-UTRAN architecture, i. e. the E-UTRAN logical nodes and interfaces between them, are defined as part of the Radio Network Layer.

E-UTRAN结构，也就是指E-UTRAN的逻辑节点和节点之间的接口，作为无线网络层的一部分被定义。

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Now layer on e-commerce, with mobile technology enabling real-time price comparisons, and the exercise of pricing becomes even more complicated.

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Rakuten offers an additional layer of support by providing e-commerce consultants and experts to advise merchants on their online business strategy, implementation, sales and marketing as well as lead and revenue generation.

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Some Web-based e-mail services like Google's Gmail offer tools to add an extra layer of protection.

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