Filtering technologies are divided into two types: Pass-through (server plug-in based) and Pass-by (standalone-based). Many networks operate in a pass-through environment, that creates "slow" points in the flow of data. Filtering solutions placed within a pass-through environment creates additional speed bumps and even a choke point if network traffic exceeds certain capacity levels. Pass-by solutions such as the R3000 are placed outside the flow of network traffic. It "watches" rather than "stops and checks" Web site requests. The result: no slowdown, even in heavy traffic situations. Most importantly, it doesn't create a point of failure.

This diagram illustrates the 8e6's Pass-by filtering technology that removes the R3000 from any inclusion in the network connection path. 

1. Inappropriate request is sent by user.
2. R3000 monitors request as it passes through the hub/switch. 
3. R3000 matches the request against its database.
4. If the Web site requested finds a match in the database, a TCP reset is sent to the Web server to kill the session (request) and a block page is sent to the client.
   

The diagram above describes the Pass-through filtering products that represent an additional network device in the connection path. When users (Client PCs) make Internet requests, the traffic flows (1) through the network control points such as a proxy server or a firewall. All user requests (2) are redirected to the Pass-through filtering product, where it determines the action to either block (3) or redirect the requests back out (3) to control points. If the Pass-through filtering product determines to pass the user’s request, the return traffic is returned from the Internet to the control points, and (4) then back to the user.