Do you have the IOS file or are you still trying to find a way to download the IOS without a valid Service Contract?
You need to also be more specific on your question. Also, if you don't know how to upgrade the 892W, you can always search and find many answers.
Just search for "Cisco upload tar file" You will find info on how to do that like this:
I know how I can upload the ios but not a tar file then file extracts
The Release Notes always contain different methods to upgrade the IOS on the appliance. Have you tried reading them?
The subject matter about how to upgrade using TAR file is all over the forum. Did you even try to search for it here?
Alternatively, if you're "busy" then I can upgrade the firmware for you (remotely). I charge US$100/hour (minimum charge of 2 hours).
Uploading the Configuration File By Using TFTP
To upload a configuration file from a switch to a TFTP server for storage, follow these steps:
Step 1 Verify that the TFTP server is properly configured by referring to the "Preparing to Download or Upload a Configuration File By Using TFTP" section.
Step 2 Log into the switch through the console port or a Telnet session.
Step 3 Upload the switch configuration to the TFTP server. Specify the IP address or hostname of the TFTP server and the destination filename.
Use one of these privileged EXEC commands:
•copy system:running-config tftp:[[[//location]/directory]/filename]
•copy nvram:startup-config tftp:[[[//location]/directory]/filename]
The file is uploaded to the TFTP server.
This example shows how to upload a configuration file from a switch to a TFTP server:
Switch# copy system:running-config tftp://172.16.2.155/tokyo-confg
Write file tokyo-confg on host 172.16.2.155? [confirm] y
Writing tokyo-confg!!! [OK]
Copying Configuration Files By Using FTP
You can copy configuration files to or from an FTP server.
The FTP protocol requires a client to send a remote username and password on each FTP request to a server. When you copy a configuration file from the switch to a server by using FTP, the Cisco IOS software sends the first valid username in this list:
•The username specified in the copy command if a username is specified.
•The username set by the ip ftp username username global configuration command if the command is configured.
The switch sends the first valid password in this list:
•The password specified in the copy command if a password is specified.
•The password set by the ip ftp password password global configuration command if the command is configured.
•The switch forms a password named email@example.com. The variable username is the username associated with the current session, switchname is the configured hostname, and domain is the domain of the switch.
The username and password must be associated with an account on the FTP server. If you are writing to the server, the FTP server must be properly configured to accept your FTP write request.
Use the ip ftp username and ip ftp password commands to specify a username and password for all copies. Include the username in the copy command if you want to specify only a username for that copy operation.
If the server has a directory structure, the configuration file is written to or copied from the directory associated with the username on the server. For example, if the configuration file resides in the home directory of a user on the server, specify that user's name as the remote username.
For more information, see the documentation for your FTP server.
These sections contain this configuration information:
•Preparing to Download or Upload a Configuration File By Using FTP
•Downloading a Configuration File By Using FTP
•Uploading a Configuration File By Using FTP
To transfer an IOS from PC to ROUTER, the following conditions must meet
* IOS image the router to have is in working condition since corrupted IOS image won't do any good
* IOS image the router to have meets the router DRAM and flash memory size. Keep in mind that maximize router DRAM and flash memory size before IOS image upgrade is always a good idea to make sure the router can fit the IOS image file and can run any IOS image version. Check out the following FAQ to find memory specification
»Cisco Forum FAQ »Cisco equipment memory chip specification
* When the router is still running the older IOS image version, backup the older IOS image to TFTP or FTP server (the next steps explain this further). This backup should perform before any IOS image upgrade. In case of unsuccessful IOS image upgrade (due to too-small DRAM size, corrupted IOS image, etc.) it is always a good to know that you are able to reverse the change by putting back the older IOS image (the one that you backup earlier) to the router
In order to transfer an IOS image typically you need to run a TFTP program on your computer. Your computer will then become TFTP server during the IOS image transfer. A simple FREE one can be found here
»Cisco Forum FAQ »How to prepare TFTP server
Note that when the router is running newer IOS image, IOS image transfer using FTP server is also supported. Using TFTP server instead of using FTP server is more common however for image transfer. The rest of this FAQ shows the use of TFTP transfer however.
It is recommended that the PC (the TFTP server) is on the same subnet as your router. Easiest way is to assign a static IP to your machine [x.x.x.100 255.255.255.0]. If there is a switch between the PC (the TFTP server) and the router, then also make sure both PC and router are within the same VLAN or the same broadcast domain.
When your network is using hub instead of switch, then there might be some collision that severely degrade the TFTP traffic flow; hence screwing up the download or upload process. In this case, it is highly suggested to use either a switch or simply back-to-back connection using crossover cable between the router and the PC.
Next go to the privilege exec prompt and type
r1#copy tftp flash
The command will ask you of four things.
1. The IP address of your server. Enter whatever PC IP address is.
2. The name of the IOS source file. Enter the exact name of the IOS file you are trying to install (including the sub-directory name and path if the file is not in the root or current directory). If you enter incorrect name or if the file is not in the right directory, the transfer will fail.
3. It may ask you for the destination filename as well. This indicates where you like the new IOS file stored and whether you like to keep the same IOS filename. Typically you choose to keep the same IOS filename and store the IOS file in current router's flash directory. Should you decide to store the file in different directory, you need to specify the exact directory path and name. You also need to specify the new IOS filename should you decide to have different filename.
4. It will also ask you if you wish you to erase your flash before copy.
For more information please follow below links : http://www.dslreports.com/faq/9817