据我所知这两个角色将不共用一个Cookie。

AFAIK The two roles won't share a cookie.

在类似的情况我有一个托管的Silverlight客户端的Web项目，并已使用的Silverlight应用程序的Web服务。

In a similar situation I had a web project that hosted a silverlight client, and a web service that was used by the silverlight app.

用户将登录到该网站并访问silveright客户端。客户一直使用param属性提供Web服务的身份验证令牌

The user would log in to the website and access the silveright client. The client had been provided with web service authentication token using the param attribute

<object data="data:application/x-silverlight-2," type="application/x-silverlight-2">                
   <param name="Token" value="<%=Token %>" />

令牌，一旦Web服务解密，包含了登录用户的ID。

The token, once decrypted by the web service, contains the logged in user's id.

现在，Silverlight客户端可以访问一个无状态的Web服务和Web服务知道哪些登录用户要求所涉及。

Now, the Silverlight client can access a stateless web service and the web service knows which logged in user the request relates to.

我一直在我的WebService和WebRole分开，使CPU沉重的作业可以由服务来处理，使Web角色服务的网页漂亮和快速。

I kept my WebService and WebRole separate so that CPU heavy jobs can be handled by the service, leaving the web role to serve web pages nice and quickly.

这是否帮助？