Other Languages - Is it necessary configure kerberos authentication in my servers?

Hi all, I'm working with Dynamics AX 2009 and I'm trying to show a Reporting Server report in Enterprise Portal though a web part. When I do it I get the error:

"An error occurred while trying to display the report from the <Report Name> folder. This error was caused by the following exception: Cannot read information from SQL Server Reporting Services. Validate that the Report Manager URL is correct.".

When I access to "Finance" tab in enterprise portal, I get the same error in all the web parts.

I have been looking for on the internet, and I have only found that is necessary to configure Kerberos Authentication and SPN in my servers, is it right??? Because now I don't have it configured.

Greetings and thanks in advance.

Use Windows authentication when you want clients to authenticate using the NTLM or Kerberos protocols. The default authentication configuration for IIS 7 enables Anonymous authentication only.

Windows authentication, which includes both NTLM and Kerberos v5 authentication, is best suited for an intranet environment for the following reasons:

• Client computers and Web servers are in the same domain.
  
  
• Administrators can make sure that every client browser is Internet Explorer 2.0 or later versions.
  
  
• HTTP proxy connections, which are not supported by NTLM, are not required.
  
  
• Kerberos v5 requires a connection to Active Directory, which is not feasible in an Internet environment

http://technet.microsoft.com/en-us/library/cc754628%28WS.10%29.aspx