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2008-10-27 14:20:58


  Part Two - Basic Setup Information
  
  In Part Two, we'll look at how to access the router, HyperTerminal, TFTP software, and Token Ring setup.
  
  Console Port Connection
  
  When you first get a router, you may wonder how to access it so you can start practicing commands, etc. The usual way is through the RJ-45-based Console port which is located on the front of the router and is clearly marked (we are assuming that the router is a 2500 series router). But what kind of cable do you need to access this Console port? To access the Console port, you need to have a console cable, which is usually referred to as a rolled RJ-45-to-RJ-45 cable.
  
  The easiest way to tell a rolled RJ-45-to-RJ-45 cable is to hold both ends of the cable together side-by-side with the clips facing away from you. You'll see eight colored pins on each of the RJ-45 ends. If the order of the colored pins is the same on each RJ-45 end, then the cable is straight. If the order of the colors is reversed on each RJ-45 end, then the cable is rolled. So, let抯 say you are holding the RJ-45 ends up and looking at them. First, look at the RJ-45 on the left. Looking at the colored pins from left to right, you notice that they are (depending on which RJ-45 is on the left and who manufactured the cable) Gray, Orange, Black, Red, Green, Yellow, Blue, and Brown. The RJ-45 on the right should be reversed when looking at the colored pins from left to right: Brown, Blue, Yellow, Green, Red, Black, Orange, and Gray. Now you know that you are got a rolled RJ-45-to-RJ-45 cable.
  
  To access the router, plug one end of the rolled RJ-45-to-RJ-45 cable into the Console port of the router. The other end will be plugged into either an RJ-45-to-DB-25 terminal adapter or an RJ-45-to-DB-9 terminal adapter, depending on the serial port you have on the back of your PC. Your PC may have a DB-9, DB-25, or both types of serial ports on the back.
  
  HyperTerminal Setup
  
  OK, you抳e now got one end of the cable plugged into the router and the other end into the serial port on the back of your PC. What do you do now? Well, you are got to make sure that the HyperTerminal application on your PC is configured correctly. For example, to access the HyperTerminal application on a 98 PC, click on the Start button in the bottom left corner, go to Programs, Accessories, Communications, HyperTerminal (If you don't have HyperTerminal, you can download it from ). The HyperTerminal window should appear with a number of icons in it. You want to double click the HyperTrm.exe icon. This opens a 揅onnection Description?dialog box. Type 揅isco?(without the quotes) in the 揘ame:?field. This can actually be any name you want but since you抣l be using it for devices, this name will be fine. Then click OK. You will now be at a 揅onnect To?dialog box. Since the router is connected directly to the serial port on the back of your PC, all you have to do is click on the small arrow to the right of the 揅onnect using:?field and choose 揇irect to Com1? All the other fields will then automatically gray out. Click OK. You will now be at the 揅om1 Properties?dialog box. Here you will set up the port settings for Com1 as follows:
  
  Bits per second: 9600
  Data Bits: 8
  Parity: None
  Stop Bits: 1
  Flow Control: None
  
  Click OK and you will be at the dialog box 揅isco ?HyperTerminal? At this point, you should be able to turn on your router, hit Enter on your PC, and you should now be accessing the router! Sometimes it takes a couple of minutes for anything to show up in this window, so be patient. If nothing shows up, check your HyperTerminal settings again. If the settings are correct, and you still can抰 access the router, go out to the website and search for some answers. They are there, so get used to using the Cisco website to troubleshoot problems!
  
  When you close the HyperTerminal session, you will be asked if you want to save the 揅isco?session. Click yes. This will save the session as an icon called Cisco.ht within the HyperTerminal Application window. Now, whenever you need to access the router, just go to the HyperTerminal Application through Start, Programs, Accessories, Communications, HyperTerminal and double click the Cisco.ht icon. Make sure your router is turned on and press Enter on your PC. Or, better yet, drag a shortcut to your desktop for easier access.
  
  Auxiliary Port
  
  You may be wondering if you can access the router using the Auxiliary port which is located next to the Console port. The answer is yes. You can access the router using either port using the same cable. However, you should use the Console port when accessing the router locally and use the Auxiliary port when accessing the router remotely through a modem. The main difference between the Console and Auxiliary ports is that the Auxiliary port supports hardware flow control and the Console port does not. Flow control paces the transmission of data between a sending device and a receiving device. Flow control ensures that the receiving device can absorb the data sent to it before the sending device sends more. When the buffers on the receiving device are full, a message is sent to the sending device to suspend transmission until the data in the buffers has been processed. Because the Auxiliary port supports flow-control, it is ideally suited for use with the high-speed transmissions of a modem. Console terminals like PC抯 and laptops transmit at slower speeds than modems; therefore, the Console port is ideally suited for use with Console terminals.
  
  If possible, don抰 use the Console port when accessing the router remotely because of security problems. For example, unprotected modems should not be connected to the Console port. The Console ports do not log users off when the carrier detect is lost, which can leave a security hole. To avoid this, use a secure modem, or connect via the Auxiliary port.
  
  TFTP Software
  
  If you抮e going to load an updated IOS on your router or you want to copy your current Flash image to your PC, you can use TFTP (Trivial File Transfer Protocol) software on your PC. What is TFTP? According to RFC783, 揟FTP is a simple protocol to transfer files, and therefore was named the Trivial File Transfer Protocol or TFTP. It has been implemented on top of the Internet User Datagram Protocol (UDP or Datagram) so it may be used to move files between machines on different networks implementing UDP. (This should not exclude the possibility of implementing TFTP on top of other datagram protocols.) It is designed to be small and easy to implement. Therefore, it lacks most of the features of a regular FTP. The only thing it can do is read and write files (or mail) from/to a remote server. It cannot list directories, and currently has no provisions for user authentication. In common with other Internet protocols, it passes 8 bit bytes of data?
  
  You are probably wondering where you can get TFTP software. Cisco offers a free version at their site:
   Another very good TFTP program is Pumpkin. This is the one we use. You can download it free at
  
  How do you use TFTP software to load a new IOS image or copy your Flash image to your PC? We抣l use Pumpkin as an example and copy our current Flash image (this is where the IOS is stored) to our PC. You should always do this before copying a new IOS Flash image to your router. If something happens to the new image when you抮e copying it to your router, you抣l have the old one as a backup.
  
  First, make sure you open the Pumpkin TFTP program by double clicking on the pumpkin.exe file, which should be on your PC if you抳e downloaded it fr
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