Firewall Questions:
Java Questions:
Trace Report Questions:
General:
Firewall Questions:
Q: Will VisualRoute work through my company
firewall / NAT server? 
A: This depends upon how your firewall
/ NAT server is configured. Please ask your network
administrator if your firewall (or NAT server)
is configured to allow PING and TRACERT to work
(which use ICMP ECHO, ECHO REPLY, and TTL EXPIRED
packets). You can test this yourself by running
these programs on your computer (For example,
try "tracert www.visualware.com"). If
these programs work, VisualRoute should work
just fine on your computer. otherwise, your firewall
(or NAT server) will have to be reconfigured
by your network administrator to allow PING and
TRACERT to work before you can use VisualRoute.
Once you can successfully run a traceroute, if you
are not seeing the Whois contact information when clicking
on an entry in the 'Node Name' or 'Network' column
of the VisualRoute report table, your firewall administrator
may also need to open port 43 to enable access to WHOIS
information. Additionally, VisualRoute Server may be
installed outside a firewall, enabling users inside
firewall access to traceroute and ping information
via a web browser.
Q: Why am I not seeing node names in the
table or lines on the map?
A: Most likely because you are running
a personal firewall product, such as ZoneAlarm, McAfee
Firewall, or Norton Internet Security (NIS
FAQ), which is preventing VisualRoute from
accessing the Internet. Please make sure that
your security software is configured to allow
VisualRoute access to the Internet. The VisualRoute
components that need Internet access are:
- java.exe (for SUN Java), or wjview.exe
- Microsoft Java VM Command Line Interpreter
- vrdns2.exe
Alternatively, changing the network properties
to point to an outside DNS server will resolve
the problem in some instances.
If you are using a company firewall please refer to
the firewall FAQ
Q: Does VisualRoute work with 'Norton Internet
Security'?
A: Yes. In most cases NIS will prompt
you to allow access for the programs below. If
not you will need to allow access for the following
VisualRoute program components.
- vrdns2.exe
- java.exe (SUN Java) or jview.exe (Microsoft
Java)
- javaw.exe (SUN Java)
- In Norton IS, click the 'Personal Firewall'
button, then 'Configure' and the 'Programs'
tab
- Click the 'Add' button,
navigate to the 'exe'
subdirectory of the
Visualroute directory,
and permit full access
to the Internet for vrdns2.exe.
Repeat for java.exe (SUN)
or jview.exe (Windows).
Q: Does VisualRoute work with Trend
Micro PC-Cillin, Internet Security v14?
A: Yes, although you will need to allow
ICMP packets as described below. This is not
necessary in v12 as this option was enabled by
default.
- Open main product window, click Network
Security
- Click Personal Firewall
- Click your current profile, and click
'Edit' instead of 'Add'
- Open the Exceptions tab and click Add again
- In the Add/Edit Personal Firewall Exception
screen enter the following:
Description: ICMP
Target: Specify all applications
Connection: incoming
Protocol: ICMP
ICMP Types: all types
IP Type: all IP addresses
Q: What does "No nodes are responding. Is
your Internet connection up" mean?
A: If you know that your Internet connection
is working, the most likely problem is that personal
firewall software installed on your computer,
or a company wide firewall is blocking VisualRoute
from access the Internet. For help with your
personal firewall, look for the product name
in bold after the questions above. For help on
a company firewall, review the company
firewall FAQ.
Q: Why is VisualRoute not working correctly
with my Linksys Router?
A: Due to a problem in recent firmware
patches on some Linksys routers, VisualRoute
does not work correctly. The problem can be resolved
in most cased by flashing the router to an older
firmware. Many Linksys firmware versions may
be downloaded from ftp://ftp.linksys.com/pub/network/.
VisualRoute does work fine on the models/firmware
versions below:
Model BEFSX41 V2 Firmware 1.45.3, Sep. 26 2003
Model BEFW11S4, Firmware v1.50, Oct. 23 2003
Java Questions:
Q: Why am I getting a Java error?
A: Visit the Java
Support web page for complete details.
If you need additional information please contact
support.
Trace Report Questions:
Q: Why do some locations appear in italics?
A: Locations that are shown in regular type known locations, locations in italics indicate an estimate was made. Estimated
locations are derived from network provider (ISP)
information.
Q: Why am I not seeing and location data
in the table or any locations plotted on the
map?
A: For VisualRoute to work correctly
you have have to set any firewall or proxy you
have to accept all incoming/outgoing ICMP and
open outgoing TCP port 43. Once this has been
done VisualRoute should give a full list of locations
and plot them on the map. On some occasions the
location appears in purple which means VisualRoute
is essentially guessing the location as it is
not 100% sure. These locations will not be plotted
on the map. There is an option in the preferences
that states if the start/end
Q: Why do some times reported
by VisualRoute differ depending
on where they are in the
trace route?
A: Depending on the accuracy of the system clock, 'ms' numbers can be correct to 5ms - that applies to all programs. But there is a big difference between pinging an address, and having that address appear in the middle of a trace route. The difference is: a router which is being pinged has to directly respond to an ICMP packet (ICMP Echo Reply). A router which appears in the middle of a trace route is simply sending an error packet back, telling the sender the packet didn't get through (ICMP TTL Expired in Transit). The latter is considered low priority and so the router put it to the bottom of its 'to-do' list, ensuring that higher-priority tasks are completed first. That is the cause of the extra delay.
Q: Why do I sometimes get 100% packet loss at hop 2?
A: 100% packet loss at hop 2 is in most circumstances due to a local router and is nothing to worry about. Most routers have two IP addresses, one for internal use and one for external use. In some traceroutes both these IPs are displayed. When this occurs it is common for the first (internal) IP address to show 100% packet loss because VisualRoute will not get any response from it. This is normal and will not be affecting your Internet connection.
Q: Why are the time stamps in the traceroute analysis table incorrect?
The time stamps in the traceroute analysis table are all supposed to be local, however there is a known issue in Java itself which can cause the wrong time stamp to be shown.
There's information on this bug here: http://www.petefreitag.com/item/171.cfm
An official bug report was filed with Sun Microsystems (the makers of Java), though it was closed as 'not reproducible' despite evidence to the contrary:
http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=6362432
We would suggest the following:
(1) Please try updating your Java VM. Most customers have found that this solves the problem completely.
(2) If this fails, try switching off the "adjust clock for daylight savings time" option. We have found that this solves the problem under older Java VMs.
If the issue still presents itself then please contact us.
General:
Q: Why don't I see the
VisualRoute icon in the Internet
Explorer toolbar?
A: Try resetting Internet
Explorer integration. Exit
Internet Explorer and then
run VisualRoute. Under Options
/ Preferences, uncheck "Internet
Explorer Integration". Exit
VisualRoute. Go back into VisualRoute
and check the option. Exit
and restart VisualRoute. Run
Internet Explorer.
Q: What do the colored
lines on the map mean?
A: Links drawn in blue
indicate known locations. Links
drawn in purple indicate that
a 'guess' was made. Guess locations
are derived from network provider
(ISP) information.
Q: What does the 'TTL
Bug' mean?
A: TTL stands for Time
To Live. All IP packets have
a TTL field and as IP packets
get passed around the Internet,
this TTL value is decreased,
usually by one at every hop.
If this field ever gets down
to zero, the IP packet is discarded
and does not reach its destination.
What this means to you is that
if you ever try to connect
to a site on the Internet that
is at a hop level greater than
your TTL, your connection will
fail.
The ICMP TTL Bug occurs in
a TCP/IP stack when the incoming
TTL value of a packet is not
reset and sent out as the outgoing
value (it should be initialized
to some default value).
Q: What is a private use
network, and why can't it
be traced?
A: Private Use networks
incorporate IP addresses that
are reserved for internal use.
When a traceroute is run, the
IP address will go through
a IP management utility which
will change the IP address
to enable it to be used externally.
In VisualRoute, for any hops
on a private use network the
geographical location will
not be shown, as these use
pseudo IP addresses. All the
other hops should work, if
there are no firewall's or
proxy servers in place.
Q: Does the VisualRoute ‘Address’ box
support copy/paste?
A: Yes. Use ctrl-c for
copy and ctrl-v on
for paste.
Q: Will VisualRoute work
with a proxy server?
A: VisualRoute uses
ICMP which is not a protocol
that can be proxied so VisualRoute
will coexist and not interfere
with a proxy. In order for
VisualRoute to work through
a firewall VisualRoute will
require that ICMP the following
outbound and corresponding
inbound message types to be
enabled.
- Outbound ICMP echo request
- Inbound ICMP echo reply
- Inbound ICMP TTL expired in transit
Q: What if I need
support?
A: Simply submit a Support
Request and we will be
pleased to help you implement
VisualRoute or answer any
questions you may have.
Q: Why will VisualRoute
not work under my Windows
2000/XP limited account?
A: VisualRoute will
work under a Windows 2000/XP
'limited' account if the user
is given read/write privileges
to the install directory.
Q: Why do I get
a "java.net.BindException:
Address in Use" error when
trying to install VisualRoute
as a service?
A: This means that
another server is awaiting
incoming connections on the
port that has been selected
(default 80). This maybe be
caused by another copy of VisualRoute
being run, possibly as a service. |
