The technical solution is to monitor access and block new offending sites as they appear.
This isn't a technical problem, it's a policy problem. You cannot possibly block every proxy out there, so you must stop the problem at its source - the employees. You need them to understand why you're blocking those sites, and why they should adhere to your policies.
First, you need to identify what your policy is, and have your employees sign a copy. An internet policy at a workplace can be really easy to create. Ours looks something like this:
Whilst at work, we expect you to work. Your work will require access to the internet. We trust you to understand that, whilst browsing social networking sites all day is tempting, it's counter-productive. Furthermore, there are certain types of content and activity that are not appropriate for a work environment. As such, this policy aims to provide a basic set of guidelines around internet access at work.
As part of this policy, we expect you to agree to the following terms:
- Your internet activity at work may be monitored and logged, in order to facilitate investigation of any inappropriate usage.
- You should use internet access for work purposes, with personal use (Facebook, Twitter, etc.) kept to a minimum.
- You must not abuse your privilege of internet access. This includes browsing pornography and other abhorrent materials, downloading files from file sharing networks, or any other activity that may cause damage or degradation to our network.
- Your activity on social media sites is your own, and we respect that. However, you agree that, as an employee, your behaviour reflects on the company. As such, you should avoid posting content that is likely to damage the reputation of the company.
- You must not distribute any of the company's intellectual property via the internet, in accordance with the non-disclosure agreement you signed when joining the company.
- You must adhere to the attached security policy.
Breach of these terms is grounds for disciplinary action, or, in severe cases, dismissal.
We provide the following guarantees:
- All logs will be safely stored in accordance with the Data Protection Act 1998.
- Upon termination of your work contract with the company, all logs related to internet activity on your account will be destroyed.
- We shall attempt to make access to the internet available at all times, at a reasonable speed.
- We shall make appropriate provisions to ensure that the network is secure and functional.
In order to fulfil our guarantees, we need our employees to adhere to this policy in its entirety. Should you have any questions about this policy, please speak to your line manager.
This document forms a binding contract with between you and the company.
____ / ____ / ________
The goal is to make it clear, short, and informative. Make sure they understand exactly why the policy is in place:
- To make sure people are actually doing the work you pay them to do.
- To help ensure that that network security is maintained.
- To make sure that the network access is fast for those who need it.
Once you've got a policy in place, you must enforce it. Penalise employees that violate the internet policy, and fire those who do it repeatedly.