View source for U620L Novatel

=AKA=
 VERIZON USB620L
 MC620
=INFO=
 QUALCOMM 3G/4G
=Config Background=
*http://www.verizonwireless.com/dam/support/pdf/user_guide/u620-linux-integration-guide-7-17-15.pdf

Available modes of the device are RNDIS and CDC-ECM.

RNDIS is a Microsoft proprietary protocol used mostly on top of USB. It provides a virtual Ethernet link to most versions of the Windows and Linux operating systems. A partial RNDIS specification is available from Microsoft, but Windows implementations have been observed to issue requests not included in that specification, and to have undocumented constraints.

CDC-ECM is Ethernet over USB.<ref>https://en.wikipedia.org/wiki/Ethernet_over_USB</ref>

=Device Modes=

End-User Mode: Enumerating CDC-ECM interface - In this mode, the device is used for a WWAN connection to the Internet for such activities as browsing or connecting to a VPN.
 pacman -Sv usb_modeswitch
 lsusb
 sudo usb_modeswitch -v 0x1410 -p 0x9020 -u 2
 ip link
 sudo dhcpd in73rf4c3

Enterprise Mode: Enumerating CDC-ECM and Modem interfaces (Optional) - In this mode, the Modem interface allows users to send AT commands to the device to configure, query, or manage the Internet connection.

I do not understand Enterprise mode, they say CDC-ECM AND modem interfaces?  Does it give both interfaces at once?  The guide asks you to compile option.c and usb-wwan.h which are definitions for USB serial mobile broadband cards.  It just involves adding a driver line that associates the device with the driver.

=udev rule=
 nano /etc/udev/rules.d/99-vzw_u620l.rules
 SUBSYSTEM=="usb", ATTR{idVendor}=="1410", ATTR{idProduct}=="9020", ATTR{bConfigurationValue}=="1", ATTR{bConfigurationValue}="2"
Save
 sudo udevadm control --reload
Notes:  https://www.raspberrypi.org/forums/viewtopic.php?f=28&t=121326&p=819522

=pfSense=
Creating an Auto-eject rule:  http://sysmagazine.com/posts/187702/

=U620L - Set CDC-ECM Permanently=
I contacted Novatel and they would not tell me how to do this.
==Put into CDC-ECM Mode==
# Go to:  http://192.168.1.1/fieldtest/
# Click Debug Mode
# You will have to restart your modem so unplug and re plug I usually wait at least 10 seconds before unplugging and 15-30 seconds before plugging back in
# By default the modem will not work in Windows as Windows does not like this mode.  Plug into a linux box or BSD box though and ask for a DHCP request and everything is cool!

You should still be able to access the web interface after this.

==Take out of CDC-ECM Mode==
# Plug into linux box or a box that interacts with CDC-ECM mode.
# Grab a DHCP release so we have access to the correct network (I think it uses NAT redirection)
# Go to:  http://192.168.1.1/fieldtest/
# Click End User Mode

==Research Study==
I hope that they do not disable this feature in an update.  I also wonder if having the modem in diagnostic mode disables firmware upgrades so I am going to track some firmware versions:

===Modem A===
Current Software Version:
1.3 (L1.218.1 M9x25MET-2.44.3 1 [2015-05-13 13:56:54])

Configuration Version:
I14.NVT,USB620.0

===Modem S===

Current Software Version:
1.3 (L1.218.1 M9x25MET-2.44.3 1 [2015-05-13 13:56:54])

Configuration Version:
I14.NVT,USB620.0

==Notes==
*I do not see a way to tell if the device is in debug mode
**This also gives you serial access too:  screen /dev/ttyACM0 115200
**I do not know the password