Network Tap - ProfiTap PROFISHARK 1G User Manual

www.profitap.com

Network TAP

The PROFISHARK integrated network TAP provides safe access to the
network for monitoring purposes. It is a passive monitoring device, meaning it
is undetectable, the original traffic staying unaltered and no extra packets
being inserted. As most of the TAP's functions are performed by dedicated
hardware circuits, it is much more reliable and error proof than SPAN ports.
In a gigabit network, the TAP has to negotiate with both attached devices for
the highest common speed. If no common speed can be found, or if one of
the devices is disconnected, the TAP propagates the error to the other at-
tached device, allowing a redundant path to be activated.
In case of power failure, it activates its bypass circuits, connecting the two
attached devices directly. The PROFISHARK integrates a high performance
fast failover circuit and a proprietary algorithm, reducing the unavailability of
the network path down to 30ms.
Note: the fast failover relies on the network setup. In case the fast failover
cannot perform, the two end devices have to renegotiate the link. This opera-
tion takes about 2 seconds.
End Device 1
DTE
DCE
DCE
DTE
Note: The user should verify that the two end devices connect together with
either a single cable, an RJ45 coupler or the unpowered TAP. The straight or
crossover cables must be employed in case of end devices that do not sup-
port Auto MDI/MDIX operate (i.e. Auto Crossover). Experienced users can
bypass this procedure.
Note: Although some vendors recommend the use of the non-IEEE compliant
"Forced Gigabit" mode, we strongly recommend activating auto-negotiation
when Gigabit speed is required. More generally, auto-negotiation should
always be enabled on both end devices in order to avoid duplex mismatch
issues.
End Device 2
DCE
DTE
DCE
DTE
1 Cable Types
Straight Through and Crossover
Straight Through and Crossover
Straight Through and Straight
Through
Straight Through and Straight
Through
Page 5