Refer to [New security requirements for RIAs in 7u51 (January 2014)](https://blogs.oracle.com/java-platform-group/entry/new_security_requirements_for_rias) .

> 
> ### RIAs must contain two things:
> 
> 
> 1. Code signatures from a trusted authority. All code for Applets and Web Start applications must be signed, regardless of its Permissions attributes.
> 2. Manifest Attributes   
> 
> 	* `Permissions` – Introduced in 7u25, and required as of 7u51. Indicates if the RIA should run within the sandbox or require full-permissions.
> 	* `Codebase` – Introduced in 7u25 and optional/encouraged as of 7u51. Points to the known location of the hosted code (e.g. intranet.example.com).
> 
> 
> 

ref another post on stackoverflow, I have the same concern that certificate is expensive for intranet use.  

[Sign applet and deploy it in intranet](https://stackoverflow.com/questions/15523521/sign-applet-and-deploy-it-in-intranet).

I am planning to start a new intranet project, should I give up the consideration on applet?  

All of my intranet user do not have the ability to connect outside internet, they are in closed network, I highly doubt the need of signed applet......?