Learn All Networking Concept In Easy Way: Personal computer

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Capture LAN Traffic

Enabling Port Mirroring on the Vigor 2820 Series

Telnet to the router and use the commands as shown in the example. In our example, LAN ethernet Port 2 will be used to connect to our PC running SmartMonitor and Port 1 will be the port we'll be mirroring (listening to):

When port mirroring is enabled, the listening port (P2 in the above example) does not have Internet access.

Enabling Port Mirroring on the Vigor 2950 or VigorPro 5510 Series

These models have a specific port which can be switched to mirror mode (marked on the front panel). Use the following telnet command to enable port mirroring:

Install DMS and your 3G Modem on your PC

Pre-requistes - Install DMS and your 3G Modem on your PC (Windows)

Before starting, you will need to have installed some USB Diagnostics software. We recommend and use in this guide HHS's software called DMS (Device Monitoring Software, USB Monitor). This is available from here and a 14 day trial can be downloaded directly from here. Also, be sure that the 3G modem or phone works correctly on your PC and that you can connect to the internet.

Step 1 - Identifying your Modem's USB IDs

Your USB modem/phone must be correctly installed any plugged into your PC. From your windows desktop, Right Click on 'My Computer' and select 'Manage':

Computer Management will open, as shown below. Within that, in the left hand pane, you will find Device Manager. If you select Device Manager, you will then see a list of all hardware components in the right hand pane, categorised by device type (hard drives, VDUs etc.). Select the category for Universal Serial Bus (USB) Controllers, as shown below. Within there, you will see several USB devices, including your hubs, as well as some USB devices you don't immediately recognise.

Your USB modem/phone may have an obvious name, so you can immediately identify it. Otherwise, your USB modem might actually be shown as a USB Mass Storage Device because the modems often have built in memory (like a USB memory stick) as well as their modem. Right click on the most likely device and it should be easier to identify the device by the manufacturer name; in the example below, you can see &quotHuawei" on the General tab.

Click on the 'Details' tab, as shown below and here you will find the USB PID/VID numbers. Note those down for later:

Step 2 - Setting up 'Device Monitoring Studio'

Your USB modem should still be connected to your PC. Load up the DMS software (as shown below). In the left hand pane, you will see your various USB devices. Select your USB modem. It may be listed with an obvious name, or may not. In our example, it's nice and clear as the Huawei modem or USB Composite Device. To be sure we're selecting the right device, right click on it and select properties. If you're really not sure, you could repeat the whole process on more than one device. On the 'diagnostics' tab, you will see the USB PID/VID identifiers; they should match the IDs which you noted down earlier in stage 1. If it doesn't match, try one of the other USB devices:

Double click the modem in the left hand panel and the screen below will appear. In the right hand panel, you will see that 'Data Recording' is already listed. Select URB View to add that to the list too. Once that is sown in the right hand panel, click Start to begin capturing.

Step 3 - Capturing the Modem Setup Data

Unplug the USB 3G modem from your PC. Wait for 10-15 seconds for any remaining USB activity to cease. Then click the 'Erase All Views' button in the DMS software; that will just remove any accumated data so far which we don't need:

Plug your USB modem/phone back into your PC and once it has been recognised by the PC. Go online to the Internet using the 3G modem. Commonly, this is done with a program provided by your cellphone company. In the example below, we're using T-Mobile and we would press the 'Connect' button:

Once you are online to the Internet, disconnect from the Internet. Again, this is usually by pressing a 'Disconnect' button in your 3G utility (as shown above for T-Mobile). After the 3G connection has disconnected, immediately go back to the DMS program screen. Right Click on the log, as shown below, and select Export. Save (export) the file using a descriptive filename, e.g. HuaweiE220.html to match the model:

Step 4 - Send us the information

Now that you have the log file, you need to email it to the support department but please also remember to provide details about the USB Modem (or cellphone) model (e.g. 'Huawei E220', or 'Nokia N95'). Sometimes cellphone companies 'debrand' the modem and put their own name or logo on it, making it difficult to tell the model. Do your best to identify it for us though!. A photo of the modem or phone is also useful.

If you can, please also collect syslog output from the router covering an attempted connection while the USB 3G modem is connected to the router.

First setup syslog, enable recording and then reboot the router so that the syslog recording will cover a full sequence of the router trying to detect the USB 3G modem. Instructions covering syslog are here

Please don't expect 'overnight' solutions; Any firmware has to be tested in-house first, even if it's beta firmware. If your modem can be supported, we will try to add it into the beta firmware release, or send you a special test version if we need further help. Also, we cannot promise to ad support for every modem, particularly if it's an obsure model which few people have requested.

Use Ethereal

Ethereal is an excellent and free third-party tool useful if you wish to examine the data that your PC is sending, at the TCP/IP level (across the Ethernet). It is often referred to as a 'sniffer'. Ethereal is not a DrayTek produced or supported product but we provide some installation documentation as a courtesy here.

Ethereal will capture data packets coming in and out of your PC and is therefore very useful to an engineer for diagnosing problems, or improving compatibility with specifical applications. Although these instructions looks long and complicated, the program is actually very easy to use and reasonably intuitive, though we would not recommend Ethereal for novices.

Download the WinPCap utility from here
Download Ethereal for Windows 98/Me/XP/2k from here.
Load the program by double clicking the dekstop icon :
The main program window will appear, similar to this :
Select Capture and Start (or press Ctrl-K):
If you get the following error, you must firstly install the WinPCap driver (see earlier) :
After selecting 'Capture' this screen will appear :

Ensure that all of the buttons in the Name Resolution section are NOT selected (i.e. they should not be depressed).
In the filename box, enter a suitable filename for the capture file. It is this file which you will examine later, or send to your support contact, so give it a name that is fairly unique, not something too generic like "log.txt":
Ensure that there is no other Ethernet/Internet activity running on your PC, such as a download; such activity will add unnecessary data to the log we're about to make.
Click the OK button and capture will commence; the following window will appear on your screen to show that capure is in progress :
Now, leaving Ethereal running, you should now immediately carry out the function/process that you are trying to diagnose. For example, if it is a VPN client connection, try the connection.
Once the process under examination/test has completed, go back to Ethereal and in the status window, click :
Depending on how much data it captures, Ethereal will take a few seconds to collate the information. Once ready, your Ethereal window will be filled with data, something like this :
You can now close Ethereal and examine the data it captured which will have been saved to the filename you selected earlier. If you have been asked for send that capture to someone, it's the same file you should send.

PING Details

A 'ping' is a small data packet which can be sent to any TCP/IP device and should be immediately echoed back to the sender, thus confirming a working route both ways.

You can send Pings from the MS-DOS prompt the router by typing PING followed by the router’s IP address, as shown below. If the pings Timeout (i.e. are not returned) then the router cannot be seen (pinged) from that PC and you have a problem.

Common diagnostic procedures include the following pings :

From PC to Router ( e.g. ping 192.168.1.1 )
From PC to external IP address (e.g. ping 194.153.0.18 )
From PC to external URL (e.g. ping www.draytek.com)

If pinging numeric IP addresses works, but pinging URLs (named addresses) doesn't then the problem is most likely with the DNS facility.

You can also ping directly from the router to internal (LAN) or External (WAN/Internet) IP addresses. To do this, access the router's Telnet interface and use the command 'ip ping'. For example:

> ip ping 192.168.1.10

Pinging 192.168.1.10 with 64 bytes of data
Received Reply from 192.168.1.10, time 20ms

firmware version do I have?

Identify your Current Firmware Version

You can view your current firmware version number from the router's web interface, here circled in red:

Understanding Router Firmware Files

Firmware should be upgraded using the Firmware Upgrade Utility which is supplied on CD with your router (as part of the router tools). The latest version of the tools is also normally included in the firmware files that you can download from the web site; always ensure that you obtain the correct firmware version for your exact router model and country.

If you download firmware, it is normally provided inside a compressed 'ZIP' file. This ZIP will typically contain the following files :

v2k60001.all - Firmware only (Filename will vary depending on model)
v2k60001.rst - Firmware as above but with factory default settings
readme.txt - Contains notes about this release of firmware, detailing changes etc.
Additional files may be included depending on model

Ensure you unzip the files before starting the firmware upgrade procedure. If you want to reset the router to factory defaults during the upgrade/reflash or you are concerned that your settings have been corrupted, you can upload the firmware file ending in .RST, otherwise use the .ALL file. Never change the filenames of the .ALL or .RST files.

Upgrading Firmware from the router's Web Interface

In later models, e.g. Vigor 2820, you do not need to use the firmware upgrade Utility; you can upgrade from the router's own web interface (System Maintenance -> Firmware Upgrade). Use the browse button to locate your firmware file on your local PC and then select upgrade:

Using the firmware upgrade utility

The firmware utility is contained within the Router Tools (on your CD Rom or download from this page). The firmware upgrade program requires you to enter the firmware's filename (which you can browse for) and the admin password for the router (if set). If you browse for the firmware file ensure that you have already unzipped the firmware files (.all and .rst). By default the browse will look for the 'all' file so remember to change the 'file type' selector if you want to use the RST file (see image, right). You also need to enter the router's IP address; if you're not sure what that is, you can press the ... button to locate it.

Once you press 'send' the utility will automatically enable TFTP mode on the router (a special mode in which it can receive the file) and then send the file. During TFTP mode, the first two LEDs on the left flash together. If you have a wireless router, you must use a wired PC (RJ45/Ethernet) to do the firmware upgrade - you cannot reflash firmware over the wireless interface.

After sending the firmware file, the router will write its new firmware to the flash memory and then reboot. This can take typically around 60 second after the file has been sent. It is very important that you do not disturb the router during this time. Once the firmware has been written and the router rebooted, the ACT LED will flash on its own normally again.

Your router is now reflashed. If you have upgraded to a new firmware version, the front page of the web configurator will now confirm the new firmware version, at the top right-hand-side of the screen.

When to use the 'RST' file

The .ALL file contains the router's firmware. If you flash the .ALL file, the router should retain all of its existing settings and after it has flashed and rebooted will resume normal operation automatically. Never change the filename or attempt to alter/edit the firmware file.

If you are making a major firmware upgrade (for example where the first digit changes, say 1.5 to 2.6), or where the readme.txt notes recommend it, you should use the RST file which will clear all existing router settings. The RST file is also necessary if your router has corrupted firmware, or invalid settings which cause it to malfunction.

A firmware corruption should not occur during normal usage but can occur if the router is subject to abnormal trauma (e.g. power/line spike or brown-out). Firmware or settings abnormalities can also occur if you have attempted to flash an invalid firmware file into the router, or tried to restore settings from an incompatible model/device. Reflashing the correct RST file will restore the router's firmware and also the 'factory default' settings of the router, wiping all existing settings. The unit must then be re-configured from scratch. Do not attempt to restore backed up settings from a file if the backup file was taken from a router with corrupt/invalid settings.

Firmware Upgrade Timeouts

If you gets a "request time out" message after pressing send, check that the PC's own IP address is in the same subnet as the router (e.g. 192.168.1.10 and 192.168.1.1 for the router). Also be sure that you have temporarily removed any software firewall on the PC which might be interfering with the upgrade procedure. If the procedure appears to complete, but then the router remains in TFTP mode (both left hand LEDs flashing together) for over 2 minutes, turn the router off/on and then try the procedure again.

Abnormal Firmware Conditions

If for some reason the router is not running normally (e.g. ACT is not flashing normally) and the router cannot be reached from telnet or the web browser, then the firmware upgrade utility may not be able to enable TFTP mode itself. Additionally, in the case of invalid settings or corrupted firmware the router may put itself automatically into TFTP mode when booted. This 'boot loader' mode is stored in a special permanent memory area (ROM) which cannot be erased by the user, so even if the main firmware is completely corrupted, boot loader mode should still be accessible.

If the router is in TFTP mode, either of its own accord, or because you manually enabled it (see below) you must use the TFTP Client Utility instead of the regular Firmware Upgrade utility. The TFTP Client program can be downloaded from the web site.

If you need to enable TFTP mode on the router manually, do as follows : Turn OFF the router (use the power switch or remove the power plug). Using a ballpoint pen, press and hold the Reset button on the rear of the router. You do not need to press hard; you will feel the button gently click. Whilst still holding the button pressed, turn the router back on. You can release the button once you can see TFTP mode is enabled frfom the LEDs (that should be almost immediately) When TFTP mode is enabled, the first and second LEDs will flash together as shown on the left.

Once the router is in TFTP mode, you can run the TFTP client :

If you have changed the router's IP address, try that IP address first. If that doesn't work because settings are corrupted, the router will revert to the default address of 192.168.1.1.

When in TFTP mode, the router's DHCP facility does not operate normally so the uploading PC must already have an IP address (either from DHCP earlier or manually set) and that address must be within the same IP subnet as the router's IP address. You cannot ping or access the web config screens when TFTP mode is running and the wireless interface (if applicable) won't function, so you must do the upgrade from a wired PC. The router will automatically enter TFTP receive mode if its firmware has become corrupted. If you enable TFTP mode accidentally, just turn the router off and on again and it will boot normally (except in the case of firmware corruption or mismatch).

Vigor 2000

For the Vigor2000 only (which does not have a Reset button), you must first enable boot TFTP mode from the console port menu; you will need the serial console cable (supplied) and use Windows Hyperterminal (or similar). Once boot TFTP mode is enabled, you use the TFTP client utility as with other models to send the firmware over the Ethernet interface. If you have very old Vigor2000 firmware in your router still (version 1.3 or older) and cannot reflash it, please contact your dealer for assistance.

How do I remotely upgrade firmware ?

This facility it depends on the model and firmware already installed. On some models, you can update the firmware from another location, via the WAN (public-facing) interface - i.e. without having to be at the same location as the router. Firstly, you must enable the facility from the router's management menu :

Then, using any FTP (not TFTP) program (we used CuteFTP in the example below) you can open an FTP connection to the router's public (WAN) IP address, using the username 'admin' and the admin password you have set on the router. A regular directory will appear as per the example shown below and you can now transfer the appropriate firmware .ALL file. After receiving the file, the router will write it to its flash rom; this can take a couple of minutes. Do not disturb the router during this time. It will reboot once it has written the new firmware, and the router should be back online shortly.

We do not recommend sending the .RST file as that will then clear our the router settings and the router will not be able to log back onto the line, so you will not longer have access to it until someone configures it locally.

After the upgrade, the router configurator main page should then show the new firmware version is installed into the router.

Cable Modem Setup (For NTL/Telewest/VirginMedia)

Ethernet Interfaces

The Vigor2200E, 2104P, 2300 and 2900 routers have two Ethernet interfaces :

The LAN interface (with optional 4-Port Switching hub). This 10/100BaseT interface connects to you local networked PCs. Each local PC is automatically allocated an IP address within your local private address range (default 192.168.1.1 onwards) by the router's 'DHCP Server' facility.
The WAN Interface. This 10BaseT Ethernet interface connects to your Broadband feed, which in the case of a Cable line is your Cable modem which has a matching Ethernet interface. The router's WAN interface acts as a DHCP client, getting it's TCP/IP properties automatically from the Cable modem.

The Web Configurator

All aspects of the Vigor2200 router are controlled from its Web Configurator. This is an HTML (web) based interface which you access through your regular web browser. Once the router is connected to your PCs you should be able to reach the Web Configurator in your browser (MSIE/Netscape etc.) on its default IP address http://192.168.1.1

Configuration

The setup of the router is actually very simple in most cases. You just need to enable broadband access. From the main router menu (Web Configurator), click on Internet Access Setup and then Static or Dynamic IP in the right hand column. You can ignore all other options and menus unless you know you need them, or advised later :

Click

then

When the router connects to the modem (via the WAN socket) it should get an IP address from the modem. This will appear in the router's Online Status screen, as shown on the right, and indicates that the router is now connected to the Internet :

Problems getting an IP Address (Blueyonder)

Using Winipcfg.exe to determine PC NIC's MAC address

Problems getting an IP Address (NTL)

Online Status

' ipconfig.exe /release '

The foolproof method :-)

cable modem

If you have already been experimenting with the router; reset it to factory settings just to be safe. With the router turned on, press and hold the RESET button on the rear of the router until the left hand LED (labelled 'ACT') starts to flicker rapidly. Then release the button and wait until the router settles back to ACT flashing steadily. The router is now factory reset.
Put the router aside for a moment (disconnect it from everything).
Connect the cable-modem to the PC via the Ethernet cable and get yourself online.
Note the MAC address of your PC's Network card (use winipcfg or ipconfig - see earlier)
Remove the ethernet cable from the cable-modem and put it into the router
Renew your PC's IP address (press 'release/renew' in Winipcfg, or ipconfig /renew. Your PC should then get a new IP address in the router's subnet (192.168.1.xxx)
Go into the router's web configurator and in ISP setup, select 'Specify a MAC Address' and enter the MAC address you noted earlier, like this example :

Once the MAC address is entered into the web configurator, click Okay to save those details.
Connect the cable modem to the Vigor's WAN port.
Turn the cable-modem off by removing the power cable (turning off the standyby button is not adequate; remove the power cable).
Wait 15 minutes (this step is not always necessary, but has sometimes been found useful)
Turn the cable-modem on
Reboot the router (turn it off, then on again)
Check the Online Status screen on the router ! If all is well, within 20-30 seconds the router will now show a WAN IP address:

Vigor ADSL Router Troubleshooting Tips

Part 1 - PCs/LAN communicating with Router

Your PC should be connected to the router via a suitable Ethernet (RJ45) cable. Does the appropriate ethernet switch LED (1/2/3/4) light up (green = 100mb/s, Amber = 10mb/s) ? The Vigor2600's Ethernet ports are auto-sensing to speed and cable configuration, so crossover/straight or uplink/normal connections will all be automatically adjusted for.

Every device on your network must an a unique IP address. The router's DHCP server facility will automatically allocate these to your client PCs, assuming that they are set to obtain their details automatically.
The router's own IP address by default is 192.168.1.1 and all local PCs must have an IP address within the same 'subnet' - for example 192.168.1.20 or 192.168.1.66. Only the last octet (and 8 bit binary number, represented in decimal - i.e. the number after the final dot) will vary - this is known as a class C subnet.

winipcfg

ipconfig.exe IP Config

In WindowsXP, you can check your PC's current IP address by opening Network Connections; if you select the LAN connection, the settings will appear on the left of the screen - like in the example below. Here we can see that the Network connection is enabled and that the PC has obtained an IP address of 192.168.1.10 :

You can obtain the same information by right-clicking on the Network Connection's icon in the system tray and selecting 'Status' :

If your PC is not getting an IP address (as described in previous sections), you need to check that your PC's TCP/IP settings are correct. As mentioned earlier, we recommend that you make use of the router's DHCP facility which is enabled by default. From Windows98/Me Control Panel/Network, check your TCP/IP Properties are like this :

For Windows XP, the LAN/Network card setup is very similar to Windows 98/Me, but the screens look a little different. Once your network card (Ethernet 10/100BaseT) is installed, it may be automatically set up correctly by default. You can check the settings from your PC's 'Network Connections' menu :

Select the TCP/IP protocol as shown below and click on 'properties' and then check that Obtain IP address & DNS Automatically are both selected :

For Apple MacOS, to select and enable the DHCP client facility on your computer, the TCP/IP control panel should be set like this for MacOS 8/9 and X respectively :

Once the addresses have been allocated by the router, they will appear in the screen above.

If you are not using DHCP (i.e. 'Obtain IP Address Automatically' as shown above) then you must manually give your PCs an IP address. This address must be within the same subnet as the router's own LAN IP address. This means that if the router is 192.168.1.1, then the other PCs must be numbered 192.168.1.nnn where 'nnn' is a number from 2 to 254. Additionally, each PC must have the 'Default Gateway' and 'DNS Server Address' set to the router's IP address (192.168.1.1 unless you changed it). None of this is necessary if you are using DHCP, hence it's recommended to rely on DHCP whenever possible.

To confirm the PC can see the router, you can use the Windows 'ping' utility. This sends a small packet to the router, which the router sends back, to confirm communication is fine. From an MS-DOS prompt, enter 'ping 192.168.1.1' - you should get replies with a time in milliseconds (e.g. 12ms).

Part 2 - Router communicating with your ISP & The Internet

The above checks should confirm that your PC and network is connected to the router correctly, so you should be able to access the router's Web Configurator interface. This is the main method for setting up, controlling and monitoring the router. Load your standard web browser (e.g. MSIE, Netscape etc) and into the address bar simply enter http://192.168.1.1 (which is the router's address). You can also get into the Web Configurator interface via the Router Tools "Smartstart" wizard. You will be asked for the router's admin password (blank by default - you can change it later) and then the main router menu should appear as shown below. This main menu 'front page' also shows the version of firmware installed in the router, at the top right hand side :

If you cannot get into the router's web configurator or Dial-Up Networking tries to dial when you try to access the internet, check your 'Internet Options' from Windows Control Panel. They should be set as shown below (varies with O/S). Select 'never dial a connection' to prevent the PC using a dialup modem (DUN) connection :
Click on LAN Settings and ensure that no proxy is set. It should look like this :

If you have a software firewall installed, for example Zonealarm, Norton Firewall etc. or SBS Proxy server, these can sometimes interfere with access to the router.

It is very simple to set up the router for standard Internet access. You will need to know your login name and password for your ISP. Go straight to the Internet Access Setup menu on the top right, in the cyan box :
Then on the next menu, be sure to select the PPPoE/PPPoA sub-menu (not MPOA!).

In the PPPoA setup screen, it's important the the boxes on the left are set as shown below (unless you are outside the UK, in which case refer to your ISP/Telco). On the right hand side, the ISP name is just for reference, but the username and password must be correct - check these with your ISP if you are not sure what to enter - these are the username and password that you use to log into your ISP.
Once everything is entered as shown above, that's all that's needed for a typical ISP setup. Click OK to save those settings:

Please note that since Autumn 2003, ADSL lines in the UK may be autodetected as PPPoE or LLC/Snap encapsulation (if you use the router's autodetect method); don't worry - those settings should also work.

Once your ISP details are set, if the ADSL line cable (RJ11) is connected to the router (normally via your microfilter/splitter), you can check that the router is online and has connected to the ISP successfully. From the main menu select >> Online Status and a screen like this will appear :
Don't be overwhelmed by all of this information; it's quite easy to follow and there are only a couple of pieces of information which are needed to confirm correct operation.
The bottom section ADSL Status confirms the modem's status :
Ready - No ADSL signal detected.
Initialising - ADSL signal detected. Initialising Modem.
SHOWTIME - Modem is trained and connected
In the SHOWTIME state the line speed and SN ratio are also shown.
Once the router is in showtime state, it will automatically log into your ISP. This is indicated by the WAN Status section. The mode should be shown as PPPoA and the IP address which the router has assumed from your ISP will be shown under IP Address . In our example, that is 215.120.215.5. Depending on your service option with your ISP, that will change each time you log in (dynamic address) or it will always be the same (static address). This is generally known as your public (or WAN facing) IP address.
In summary, if you have a public IP address shown, the router is set up and logged into your ISP correctly. You should now be able to surf the internet ! Try entering a web address into your browse (for example www.draytek.co.uk !).

From PCs on your network, you should be able to ping IP addresses, and URLs on the Internet. This is normally done from the command (DOS) prompt in Windows. For Mac users, various ping utilities are available. Try a ping like this :
```
ping www.draytek.co.uk
```
You should get some ping replies, and the time to reply is shown for each (e.g. 50ms). If pinging a URL like that does not get a reply, try to ping an IP address (it must be one which is active and that can reply!) :
```
ping 194.153.0.18
```
If the numeric IP address replies, but the URL (web address) doesn't, then that suggests that the PC has a problem resolving URLs (converting from a URL to an IP address). URLs are resolved by use of a DNS server; the router can act as a DNS proxy to your ISPs actual DNS servers. The DNS servers are set on the PC, or if left blank, on the router either automatically when it connects to the ISP, or manually from the router's LAN TCP/IP menu.

If the PCs on your network cannot ping the Internet, you can check if the router itself can ping the internet. If you telnet to the router (see main FAQ for details on how to run telnet) then you can try to ping an external IP address (i.e. one elsewhere on the internet). If the ping comes back, then that confirms that the router is happily connected to the Internet and can send/receive data. Pings will have a trip time, for example 97ms.

You can also ping from the router to an internal IP address, e.g. ip ping 192.168.1.10. Note that the IP address example given above may not be a real address - you must ping a known/real/active IP address. If the address doesn't exist, or is unreachable, you will not get a ping reply.

If you cannot get the router logged into the ISP, you can telnet to the router and check the call log (log -c). If it shows a CHAP failure then either your username or password is almost certainly incorrect. The "ISP Name" field is arbitrary so you can put anything you like in there, but the username and password must be correct. Windows 95/98/2000/ME/XP all have a Telnet program built in. For other Operating systems, you can normally download a freeware Telnet utility. To run regular Telnet under Windows select as follows :

Windows2000 and WindowsXP have a 'DOS' based Telnet program, so you cannot capture text with it. Instead you can use Windows Hyperterminal, and select Port 23 (telnet) connection rather than a modem or COM port:

Here is an example log :

In the above log, the router logged in successfully. If your ISP "idle timeout" is set to always-on (-1) then the Dial-Up Triggered by.... line will not show. When the LINK light on the router comes on, the router is successfully logged in.

In the above example log, the login has failed, most probably due to an incorrect username or password.
If you need to capture the log text, for example to send it to your support contact for examination, you need to open a Telnet session to the router, as shown above and start a text capture (give it a suitable filename, for example fred01.txt.
Then enter the appropriate log commands to display the logs, and finally close the text capture, which will leave you with a text file you can email.