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You can configure some of
the program's options by selecting Settings
=> Options in the menu.
General
Auto-start
capturing – check this box if you
want CommView to start capturing packets immediately after
launching the program. Please select the channel that you would
like to monitor from the drop-down list.
Disable
DNS resolving – check this box if you
don't want CommView to perform reverse DNS lookups of the IP
addresses. If you check it, the Hostname
column on
the Latest
IP Connections tab will be
blank.
Convert
numeric port values to service names – check this box if you
want CommView to display service names rather than numbers. For
example, if this box is checked, port 21
is shown
as ftp,
and port 23
as
telnet.
The program converts numeric values to service names using the
SERVICES file installed by Windows. You can find it in the
\Winnt\system32\drivers\etc folder. You can edit this file manually
if you want to add more ports/service names.
Convert
MAC addresses to aliases – substitute MAC addresses
for aliases on the Packets
tab.
Aliases
can be
assigned to MAC addresses using the Settings
=>MAC Aliases menu command.
Convert
IP addresses to aliases – substitute IP addresses
for aliases on the Packets
and
Statistics
tabs.
Aliases
can be
assigned to IP addresses using the Settings
=>IP Aliases menu command.
Convert
IP addresses to hostnames in the "Packets" tab – check this box if you
want CommView to show resolved hostnames rather than IP addresses
in the Packets
tab. If this
box is checked, CommView will first attempt to find an alias for
the given IP address. If no alias is found or the previous box
(Convert
IP addresses to aliases) is not checked, CommView
will query the internal DNS cache for the hostname. If no hostname
is found, the IP address will be displayed in numeric
form.
Display
vendor names in the MAC addresses – by default, CommView
replaces the first three octets of the MAC address by the adapter
vendor name in the Packets
tab. Uncheck
this checkbox if you want to change this behavior.
Capture
Damaged Packets – because of the distance,
radio interference, and other physical phenomena, some packets
received by your wireless adapter might be damaged, i.e. contain
partly or fully invalid data. Check this box if you want the
program to capture and display such packets. This option has both
drawbacks and advantages. The advantage is that if you are located
far away from WLAN stations and/or access points, a high percentage
of packets might be broken, and enabling this option would allow
you to see more data, even though the data might be partly damaged.
However, the drawback is that you would see some packets with
invalid data, e.g. you might see IP packets sent to non-existent IP
addresses. Also, when this box is checked, the program will try to
decrypt those WEP- or WPA-encrypted packets in which the Integrity
Check Value is incorrect, but the headers appear to be
valid.
Discard
damaged packets in the scanner – when this option is
enabled, CommView will ignore damaged packets while scanning
channels and will only list nodes that transmit valid
packets.
Active
node discovery using PROBE REQUEST – if this box is checked,
the program sends PROBE REQUEST packets periodically. Such packets
facilitate the discovery of those Access Points that do not
broadcast their SSID. Note that using this option may make your
adapter transmit packets, so it would no longer be completely
stealth. This option is not available for some cards.
Show
gridlines – makes the program draw
gridlines in all packet lists.
Secondary
channel is below the primary channel in 802.11n 40 MHz mode
– by default,
the secondary frequency channel in 40 MHz 802.11 networks has a
higher frequency than the primary channel. If you're capturing
packets in a network environment where the secondary channel has a
lower frequency, check this box. This option is available only if
your adapter supports 802.11n.
Memory Usage
Display
Maximum
packets in buffer – sets the maximum number
of packets the program stores in the memory and can display in the
packet list (2nd
tab). For
example, if you set this value to 3000, only the last 3000 packets
will be stored in the memory and packet list. The higher this value
is, the more computer resources the program consumes.
Note that if
you want to have access to a high number of packets, it is
recommended that you use the auto-saving features (see
Logging
for more
information): it allows you to dump all the packets into a log file
on the hard drive.
Maximum
Latest IP Connections lines - sets the number of lines
the program displays on the Latest IP Connections tab. When the
number of connections exceeds the limit, the connections that have
been idle for the longest period of time are removed from the
list.
Driver
Buffer - sets the driver buffer
size. This setting affects the program's performance: the more
memory allocated for the driver buffer, the fewer packets the
program drops. For low traffic LANs and dial-up connections, the
buffer size is not critical. For high traffic WLANs, you may want
to increase the buffer size if the program drops packets. To check
the number of dropped packets, use the File
=> Performance Data menu command while
capturing is on.
Latest IP Connections
Display
Logic –
allows you to select the Latest IP Connections layout that best
suits your needs. Selecting an item from the drop-down list will
display the description of the selected logic. In most cases, it is
recommended to use the default Smart
logic.
Define
Local IP Addresses – you should use this tool
if you monitor WLAN traffic with many pass-through packets and a
mixture of external and internal IP addresses. In such a situation,
CommView for WiFi doesn't "know" which IP addresses should be
treated as local and might reverse the IP addresses in the Source
and Destination IP columns. This tool allows you to define the
local network addresses and subnet masks to make sure the Latest IP
Connections window works correctly. This will work only if you use
the default Smart
logic.
Colors
Packet
color – sets the colors for
displaying different kinds of packets (Normal, Bad CRC, Bad ICV) on
the Packets
tab.
Colorize
Packet Headers – check this box if you want
CommView to colorize packet contents. If this box is checked, the
program displays the first eight packet layers using different
colors. To change a color, select the type of header for
which you want to change the color and click on the colored
rectangle.
Formula
syntax highlighting – sets the colors for
highlighting keywords in formulas in the
Advanced Rules
window.
Selected
byte sequence color – sets the font and
background color for displaying the byte sequence that was selected
in the decoder tree. For example, when you select the "TCP" tree
node, the corresponding part of the packet will be highlighted
using these colors.
Management
frame color – sets the colors for
different types of Management frames. Color is used in the
Protocol
column of
the Packets
tab to show
the corresponding frame types
Decoding
Always
fully expand all nodes in the decoder window – check this box if you
would like to have all nodes in the decoder windows automatically
expanded when you select a new packet in the packet
list.
Expand
the last nodes – check this box if you
would like to have the last node(s) in the decoder window
automatically expanded when you select a new packet in the packet
list and set the number of nodes to be expanded. By default, the
first node is expanded. This setting has no effect if the
Always
fully expand all nodes in the decoder window box is checked.
Expand
level – set the number of levels
to expand. This defines the "depth" of tree node
expansion.
Decode
up to the first level only in ASCII export – this option affects the
decoding format used when you export a packet log or individual
packet as an ASCII file with decoding. If this box is checked, only
the top-level nodes will be saved. For example, if you save a
TCP/IP packet when this option is disabled, all Type
of service sub-nodes are saved. When
this option is enabled, these sub-nodes are not saved. Checking
this box makes the output ASCII file less detailed and more
compact.
Ignore
incorrect checksums when reconstructing TCP sessions –
this option
affects the way CommView treats malformed TCP/IP packets when
reconstructing TCP sessions. By default, this option is on, and
packets with incorrect checksums are not discarded in the process
of reconstruction. If you turn off this option, packets with
incorrect checksums will be discarded and not displayed in the TCP
reconstruction window.
Include
packet numbers when reconstructing TCP sessions –
check this box
if you'd like the chunks of data shown in the TCP session
reconstruction window to be prepended by the packet numbers that
correspond to these chunks of data.
Search
for the session start when reconstructing TCP sessions
–
if this box is
checked, the program will attempt to find the beginning of the TCP
session when you reconstruct it. If it is not checked, the session
will be reconstructed only from the selected packet, i.e. earlier
packets will be discarded.
Decompress
GZIP content – check this box if you want
CommView to convert GZIP-compressed HTTP content into readable text
in the TCP Session Reconstruction windows. GZIP content is
decompressed only when the display type in the window is set to
"ASCII."
Reconstruct
images – check this box if you want
CommView to convert binary HTTP streams that represent images into
viewable JPG, BMP, PNG, and GIF pictures in the TCP Session
Reconstruction windows. Images are shown only when the display type
in the window is set to "HTML." Images are never shown within the
HTML pages to which they belong, as they are transferred by the
server in a separate HTTP session.
Use
IPv4-style endings in IPv6 addresses –
if this box is
not checked, IPv6 addresses are shown using hexadecimal symbols
only, e.g. fe80::02c0:26ff:fe2d:edb5. If this box is checked, the
last 4 bytes of IPv6 addresses are shown using the IPv4-style
dotted notation, e.g. fe80::02c0:26ff:254.45.237.181.
Reassemble
fragmented IP packets –
check this box
if you'd like the program to reassemble IP packets that are
fragmented. By default, fragmented IP packets are displayed as they
were received from the wire, in their original form. If this option
is turned on, the program will maintain an internal buffer of
fragments and will attempt to "glue" them, displaying only the
results of successful reassembly.
Display
signal level in dBm – check this box if you'd
like the program to display signal strength in dBm rather than in
percentile format. The availability of signal level in dBm depends
on the wireless adapter model being used. Please refer to
the
Understanding Signal Strength chapter for more
information.
Default
display type – select the display type
value from the drop-down list that you want to set as default for
the TCP Session Reconstruction function. The available values are
ASCII, HEX, HTML, and EBCDIC.
VoIP
Note: The
VoIP analysis module is only available to VoIP license users or
evaluation version users who selected VoIP evaluation mode.
Disable
VoIP analysis – disables capture and
analysis of VoIP data. Check this box if you don't plan to work
with VoIP and want to minimize the usage of computer resources by
the application.
Maximum
records in the list – limits the number of
displayed and processed VoIP events. When the number of records
exceed the specified limit, older records are deleted from the
lists.
Ignore orphan RTP
streams – when this box is
checked, VoIP analyzer will ignore captured RTP data streams that
don't have a parent signaling session. Orphan RTP streams typically
appear if packet capturing was started in the middle of a call, or
the signaling protocol is unknown to the application (i.e. not SIP
and not H.323), or the signaling protocol was sent in a
non-standard manner (e.g. encrypted or as part of some other
session). Such streams are still available for analysis, and
sometimes for playback. Please see the
Call
Playback chapter for more detailed
information on playing VoIP calls. If you are not interested in
such orphan streams and want to save
on computer resources, please disable this option. Note that when
orphan streams are not ignored, VoIP analyzer may mistakenly
identify data transferred over UDP protocol as RTP streams.
Generally, this is not an error, as RTP packets don't have a
standard uniform signature, so such "false positives" are
ok.
Ignore
damaged packets in VoIP analyzer – when this box is
checked, wireless packets with bad CRC will be discarded by the
VoIP analysis module. This prevents the application from creating
"ghost" signaling or media streams that may appear if packets with
bad CRC are not dropped.
Geolocation
Geolocation is
IP-to-country mapping for IP addresses. When this functionality is
enabled, CommView checks the internal database to provide
information on the country any IP address belongs to. You can
configure the program to show ISO
country code, Country
name,
or Country
flag next to any IP address.
You can also disable geolocation. For some IP addresses, such as
reserved ones (e.g. 192.168.*.* or 10.*.*.*) no information on the
country can be provided. In such cases, the country name is not
shown, or if you use the Country
flag option, a flag with a
question mark is displayed.
As IP allocation is
constantly changing, it's important that you always have an
up-to-date version of CommView. A fresh, up-to-date database is
included in every CommView build. A fresh database has 98%
accuracy. Without updates, the accuracy percentage falls by
approximately 15% every year.
Miscellaneous
Hide
from the taskbar on minimization – check this box if you
don't want to see the program's button on the Windows taskbar when
you minimize the program. If this box is checked, use the program's
system tray icon to restore it after minimization.
Prompt
for confirmation when exiting the application – check this box if you
would like the program to ask you for a confirmation when you close
it.
Auto-scroll
packet data window – if this box is checked,
the program scrolls the text of the packet data window
automatically when you select a new packet from the packets list
(but only if the text does not fit into the window). This is useful
when you want to see the contents of a long packet without manually
scrolling the window.
Auto-scroll
packet list to the last packet – if this box is checked,
the program automatically scrolls the packet list in the
Packets
tab down to
the last received packet.
Auto-sort
new records in Latest IP Connections – if this box is checked,
the program auto-sorts new records on the Latest IP Connections tab
based on the user-defined sorting criterion (e.g. ascending
order of remote IP addresses).
Smart
CPU utilization control – if this box is checked,
the program tries to decrease CPU utilization when capturing
high-volume traffic by decreasing the quality and frequency of the
screen updates.
Run on
Windows startup - if this box is checked,
the program is launched automatically every time you start Windows.
Under Windows Vista and higher, this box is disabled if UAC is
enabled. This is a limitation of Windows Vista and newer Windows
versions that prevents applications with elevated rights from
loading on startup. If this feature is important, disable
UAC.
Run
minimized – if this box is checked,
the program is launched minimized and the main window is not
displayed until you click on the tray icon or taskbar
button.
Enable
automatic application updates – check this box to let
the program connect to the TamoSoft Web site periodically and check
for updates. Use the Interval
between checks box to configure how often
the checks should be made.
Plug-ins
This tab is used by
3rd
party plug-ins
for performing configuration tasks. Please see
Custom Decoding
for more
information.
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