upgradefw imagefile.tar url username passwd

Remote upgrade of the firmware (kernel and root filesystem images).

imagefile.tar	the name of the file containing the firmware image
url	can be localhost, or the address of the FTP or HTTP server, can also be an IP address, prefixed by ftp:// or http:// respectively; if no prefix is specified (eg. cypress.bc.ca) then ftp:// is used.
username	username to access FTP server (ignored when url is prefixed by http:// or url is localhost). Must not contain special characters.
passwd	password to access FTP server (ignored when url is prefixed by http:// or url is localhost). Must not contain special characters.

Notes:

When localhost is specified as the url, the image file must be located in /tmp on the modem.

Examples:

where openctm-1.3.0-r1590.tar is the image file, cypress.bc.ca is the FTP server, guest is the username of the FTP server, and guestpw is the password of the FTP server :
```
cmd upgradefw openctm-1.3.0-r1590.tar cypress.bc.ca guest guestpw  
```
where openctm-1.3.0-r1590.tar is the image file, and /tmp is the location of the image file :
```
cmd upgradefw openctm-1.3.0-r1590.tar localhost
```
where openctm_r2_0_1_2171.tar is the image file and http://www.cypress.bc.ca/repository/openctm/ctm200/bin/ is the HTTP path :
```
cmd upgradefw openctm_r2_0_1_2171.tar http://www.cypress.bc.ca/repository/openctm/ctm200/bin/
```