Have You Used Optical TAP Cassette Before?

In today’s intelligent data center, real-time monitoring has become an important part to secure the network for better performance. Is there any device that can achieve both data transmission and monitoring at the same time? Certainly, optical TAP (traffic access point) cassette is the ideal solution. This hardware tool enables you to monitor every bit, byte and packet of your data information. If you are not familiar with this type of device, the article is going to explain it to you.

Basics of Optical TAP Cassette
Optical TAP is an access point install in networks that provides real-time monitoring of ports. Typically, the data is used to monitor for security threats, performance issues, and optimization of the network. Optical TAP cassette is a passive device that integrates TAP functionality into cable patching system, which requires no power of its own and does not actively interact with other components of the network. Instead of two switches or routers connecting directly to each other, the optical TAP cassette sits between the two endpoint devices connected directly to each of them. Then traffic is copied and once the traffic is tapped, the copy can be used for any sort of monitoring, security, or analytical use. Thus, TAP cassettes are a key component of any visibility system.

TAP cassette

Operation Principle of Optical TAP Cassette
Optical fiber is designed to send light from a transceiver through a thin glass cable to a receiver on the other end. Instead of connecting directly to each other, each of the two endpoint nodes (switches, routers, database, etc) are connected to network ports on the TAP cassette. A TAP cassette usually integrates both network ports and monitoring ports in a module and it includes an optical splitter, which “splits” off a percentage of the input power and sends it to a monitoring device. As shown in the figure below, we can connect the TAP cassette to the Switch X and Switch Y via network ports and connect TAP cassette to monitoring device via monitoring ports.

TAP cassette
By using the splitter, we can see that a part of TX data of Switch X transmits to RX of Switch Y and another part of TX data of Switch X transmits to monitor. Similarly, a part of TX data of Switch Y transmits to RX of Switch X and another part of TX data of Switch Y transmits to monitor. The monitored traffic is thus separated into two transmit (TX-only) signals, one copy from endpoint A (Switch X), and one copy from endpoint B (Switch Y). The proportional share of light for each path (transmit to network and monitor) is known as the split ratio. The split ratio is written as a combination of two percentages. The first number is designated as the network percentage. The second number is the monitor percentage. They always add up to 100 percent. For example, a common split ratio for traditional 1Gb short-range links is 70/30, where 70% of the light continues to the network and 30% is allocated to the monitor port.

Connecting Your Optical TAP Cassette
Before you connect the fiber optic cable into a TAP cassette, make sure that the TAP cassette is compatible with the cables. At present, TAP cassettes are mainly available in LC and MTP two port types. Take the MTP TAP cassette for example, and following steps will show you how to connect an optical TAP cassette to your network:

TAP LGX cassette

To connect TAP cassette to the network (in-line links)

  • Step 1, connect MTP network port to switch A using a MTP cable.
  • Step 2, connect another MTP network port to switch B using a MTP cable.

To connect TAP cassette to the monitoring device

  • Step 1, connect TAP monitor port to monitoring device using a MTP cable for switch A monitoring.
  • Step 2, connect another TAP monitor port to monitoring device using a MTP cable for switch B monitoring.

Optical TAP cassette makes it possible to monitor and transmit optical data simultaneously. Technicians are able to gather valuable data analytics and detect network traffic issues in a timely manner. Optical TAP cassette has been widely used in data centers and telecom carrier networks. If you are interested, please visit FS.COM for more information.