REI TALAN 3.0, Руководство пользователя

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MANUAL TEST FUNCTIONS
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VoIP (Overview, Connections, Mirroring…)
Voice over IP (VoIP) technology encodes speech for transmission over IP (internet protocol)
networks. TALAN has the ability to monitor IP packet traffic using its built-in network interface
card (NIC) and to display, analyze and save those packets to assess the threat of illicit VoIP
phone system intrusions. With the
TALAN 3.0 , VoIP Plus+ was added to help identify VoIP traffic
based upon characteristics of VoIP packets. VoIP Plus+ is intended for Ethernet type traffic, and
brings with it several features that normal Network Analyzers either cannot do, or can do with
great difficulty or extensive filtering.
To analyze VoIP traffic with either VoIP Analysis or with VoIP Plus+, the TALAN should be
connected via the TALAN network port (under the right grip) between the phone and the phone
system network. Some VoIP phone handsets have a non-switched internet port which can be
connected directly to the TALAN’s network port allowing the TALAN to see the VoIP traffic
between the phone and the network.
A common scenario is a phone with no extra port or a phone with a switched port allowing
network access but does NOT include the phone traffic. In these scenarios (no network port or
switched port that does not include phone traffic), the VoIP Test Adapter must be used in-line
with the phone network line (see diagram below).
Using an additional CAT5 cable (included), connect the VoIP Test Adapter in-line using the
PHONE and NETWORK ports on the test adapter. This allows normal phone activity to take
place. Using a 2
nd
additional CAT5 cable (also included), connect the TALAN network port
(under right grip) to either the Rx or Tx port on the test adapter to monitor either the
information being received (Rx) by the phone or transmitted (Tx) from the phone. The adapter
acts as a passive tap on 10/100 Mbps networks. If connected to a network that operates at
faster rates (1Gbps+), the tap is designed to force the network to auto-negotiate down to the
100Mbps rate compatible with TALAN.
Caution – Phones and PCs may auto-negotiate the physical hardware interface setup with the
router/switch/hub that they are connected to. Typically this only sets the speed, duplex, etc.,
but sometimes this also means they can swap the lines normally used for Rx and Tx. The way to
tell is to look at the Source IP Address. If the Source IP address is the IP address of the phone,
then you are on the Tx lines of the phone. If the DstIP address is the IP address of the phone,
then you are on the Rx lines of the Phone.