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Tool Kit Tips - Portable TAPs

SmartNA™ Portable TAP

Did you know that the acronym TAP stands for Test Access Point? Portable TAPs were originally designed as a diagnostic tool for network engineers and technicians. They were a staple in the network engineer’s tool kit. TAPs would temporarily connect to a link and send a mirror copy of live traffic to a diagnostic program like Wireshark, providing clear visibility to network traffic. The engineer could then look for patterns that may be causing network issues like delays, unresponsive links, or outright outages. Once the evaluation was complete, the TAP would be disconnected from the link and returned to the tool kit.

TAP (R)evolution

In 1997, Network Critical came up with a revolutionary idea. If network traffic visibility helps solve temporary network problems, perhaps it could help manage other network issues. It turns out that TAPs are very helpful in actually pre-empting network issues, not just solving them after they become a problem. TAPs, in fact, can be a beneficial tool for the critical 3Ps; planning, protection, and performance. In order for network managers to accurately plan for the future, protect from malicious data and enhance network performance, traffic visibility must be permanent, complete, and accurate.

To that end, Network Critical developed a portfolio of intelligent TAPs, called SmartNA™, that permanently attach to network links. These TAPs provide ongoing visibility to a variety of specialized network tools that analyse traffic data, secure network links and improve network availability and performance. They are invisible to the network, do not introduce latency, and are simple to install and manage.

As network complexity and speed increase, Network Critical continues to innovate. Over the years since the SmartNA™ introduction, there have been new developments to our TAP family. Smart features such as aggregation, port mapping, filtering, and virtual in-line bypass switching have been introduced. Newer TAPs can now support switches and tools at network speeds from 10Mbps to 400Gbps. Network Critical has also added specialized modules for other advanced features. These permanent TAPs are now being deployed by government, financial, university, enterprise, and small business networks all over the world.

Back to the Future

As TAP technology marches on and new permanent fixtures and features are introduced, there is still a large market for tried and true portable visibility. Not all networks are advancing to 100Gbps/400Gbps rates. Many smaller networks are performing nicely in the 10Mbps to 1Gbps range. There are also many temporary networks being built and torn down every day. There are businesses where permanent TAP deployment on every link may be beyond budget limitations.

Networks that are not candidates for advanced, permanent TAP solutions still have the option for complete and accurate visibility when needed. The answer is to look back at portable TAPs.

The SmartNA™ Portable TAP is a modular, 10/100/1000Mbps stand-alone network TAP. The small, portable single-slot chassis supports a wide range of TAP modules. The modules include four ports that can be set for varying speeds from 10Mbps to 1Gbps in both fail-safe copper and optical fiber configurations.

SmartNA™ Portable TAP

The portable chassis supports dual redundant power supplies. Hot-swappable modules are programmable for various modes of operation.

  • In aggregation mode, up to two tools may be connected. Each tool will receive a mirror copy of full duplex traffic from the link.

  • In breakout mode, a single connected tool will receive separate streams allowing discreet analysis of bi-directional traffic.

  • Regeneration mode allows a single stream of data to be regenerated and sent to three separate connected tools simultaneously.

  • All three modes can easily be set or changed through the Command Line Interface (CLI) included on the rear of the portable chassis.

Portable Passive Optical Fiber TAPs

Many optical networks may also take advantage of portable TAPs in the tool kit. Network Critical also makes a line of passive optical TAPs that are small, easily transportable, require no power, and provide four breakout ports for connecting analytic equipment. These TAPs, designed for higher speed access to live traffic pass full duplex traffic including errors for complete and accurate visibility.

Optical TAPs come in a variety of splits. A split determines the amount of optical light budget that flows directly to the live network compared to the amount of light that is diverted to the analytic tool. Note that depending on speed and reliability requirements, the split ratio may vary by network. When properly configured, there is sufficient optical bandwidth to send a complete data stream through the TAP to the live network using an only portion of the light budget. The balance of the light is diverted to the analytic equipment sending a mirror copy of live data.

It’s Not Complicated

While there are many options for portable TAPs and proper configuration is critical to a successful deployment, installing portable TAPs is relatively simple. Network Critical has experts standing by to answer your questions and assist with the specific design parameters.

Go to for more information or to talk with a TAP expert. Permanent TAPs are a critical component for network protection, performance, and planning. However, portable TAPs are still very much in demand for many smaller, temporary or mobile network environments. It is not an either/or question. In many cases, having both is the best option.





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