Now that we’ve gone over some reasons why you want to utilize network TAPs in your network, the next logical question that comes to mind is, Where do you TAP your network?
Some people will say you should TAP every link in your network, but I know that’s not a feasible option for many companies. Instead, you should work with your Network TAP vendor to design a strategy that will provide complete network visibility, while adhering to your budget. When designing a new network, one idea to keep in mind is that even if you aren’t planning on deploying a monitoring device in a specific part of the network today, including a TAP in the design can speed up future deployment, troubleshooting, as well as quickly pinpoint the source of any issue that may cause enterprise disruption. With that in mind, Garland Technology recommends 3 places to TAP your network: the Physical Layer, the Edge of the Network, and the Data Center Core.
Using Network TAPs in the physical layer, often called the access layer, will provide 100% visibility for your out-of-band monitoring tools like Wireshark, network analyzers, DPIs, and lawful intercept applications. Out-of-band monitoring devices aren’t effective if they don’t see 100% of the network traffic that can then be compared to your network’s normal baseline. By placing TAPs strategically throughout the physical layer, you can compare traffic to the baseline to not only help spot suspicious activity, but ensure your monitoring tools are deployed properly.
The edge of the network is where the battle for network security takes place. By using network TAPs at the edge, you ensure 100% uptime for inline security tools (and it’s likely you have a whole stack of them). Web application firewalls for virtual platforms, next generation firewalls, data leakage prevention, packet capture, and intrusion prevention systems are just some of the tools that are active at the edge. With so many tools operating in one place it’s important to make sure that your network is designed so that each tool has the traffic needed to do its job - protecting your network.
Today’s data centers power countless applications and service delivery solutions for enterprises. It only makes sense that Network TAPs will also play a critical role within the data center. But the underlying issue is usually lack of space. The resulting solution is likely to utilize a modular network TAP chassis, feeding into purpose-built packet brokers, not only to save rack space, but to make the cabling manageable as well. With this solution you are able to TAP multiple links, and then filter, aggregate and load balance to multiple monitoring/analysis tools, ensuring no dropped packets.
So there you have it, a network TAP strategy that will ensure you have the visibility you need for your monitoring and security tools to work effectively.
Looking to add Network TAPs solution to your security deployment, but not sure where to start? Join us for a brief network Design-IT consultation or demo. No obligation - it’s what we love to do!
If the inline security tool goes off-line, the TAP will bypass the tool and automatically keep the link flowing. The Bypass TAP does this by sending heartbeat packets to the inline security tool. As long as the inline security tool is on-line, the heartbeat packets will be returned to the TAP, and the link traffic will continue to flow through the inline security tool.
If the heartbeat packets are not returned to the TAP (indicating that the inline security tool has gone off-line), the TAP will automatically 'bypass' the inline security tool and keep the link traffic flowing. The TAP also removes the heartbeat packets before sending the network traffic back onto the critical link.
While the TAP is in bypass mode, it continues to send heartbeat packets out to the inline security tool so that once the tool is back on-line, it will begin returning the heartbeat packets back to the TAP indicating that the tool is ready to go back to work. The TAP will then direct the network traffic back through the inline security tool along with the heartbeat packets placing the tool back inline.
Some of you may have noticed a flaw in the logic behind this solution! You say, “What if the TAP should fail because it is also in-line? Then the link will also fail!” The TAP would now be considered a point of failure. That is a good catch – but in our blog on Bypass vs. Failsafe, I explained that if a TAP were to fail or lose power, it must provide failsafe protection to the link it is attached to. So our network TAP will go into Failsafe mode keeping the link flowing.
Single point of failure: a risk to an IT network if one part of the system brings down a larger part of the entire system.
Heartbeat packet: a soft detection technology that monitors the health of inline appliances. Read the heartbeat packet blog here.
Critical link: the connection between two or more network devices or appliances that if the connection fails then the network is disrupted.