Black Box TS250A, Manual, Page: 52 / 64

What happens if my TAP loses power?
Chapter 5 FAQ and Troubleshooting 52
rev. 1
What happens if my TAP loses power?
If your copper TAP loses power (optical TAPs do not require power),
the TAP will not be able to send data to the analyzer. You will
temporarily lose network connectivity, but it will be re-established as
soon as the two devices connected to the Link ports can renegotiate a
connection with each other. This could take a few seconds and is
completely dependent on the network and the devices.
What latency does a TAP create?
A Black Box TAP’s latency is 200-250 nanoseconds. This is the time it
takes to receive the packet, process and copy it, and send it out the
other side (Link A to Link B). Optical TAPs are non-electronic and do
not introduce any delay.
Are the analyzer ports “send only”?
Yes, the analyzer ports are send only. The full-duplex and Copper
Aggregator TAPs are incapable of sending data from the Analyzer side
of the TAP to the Link (or network) side of the TAP.
The “A,” “B,” or “AB” ports on the Analyzer side of the TAP must be
capable of both transmitting and receiving data to negotiate a
connection with the analyzer and they do this through the physical
interface. The physical interface is responsible for negotiating a bi-
directional connection with the analyzer and unidirectionally sending
data from the TAP to the analyzer.
There is no physical connection between the receive port on the
Analyzer side of the TAP and the TAP’s internal processor. Therefore,
the TAP cannot transmit data from the analyzer back to the Link/
network side of the TAP.
Can I daisy chain an Aggregator TAP?
Yes, you can daisy chain TAPs, but it is not recommended because of
the negotiation time and latency introduced by the TAP. Although the
latency is very small, if the packets do not reach their destination fast
enough and the receiving device has a low MTU (maximum