Fixed: Cisco VPN Client, a Huawei 3G usb key and network sniffing

I ran into a problem widely documented on the Internet. Using a USB 3G Huawei Internet key (in particular for me it is an E1692), for some reason the vpn created with Cisco VPN Client does not work. Indeed, the vpn is regularly established, but no packet is effectively routed through the vpn itself. Googling around I found some indications about the Deterministic Network Adapter (DNE) and the opportunity to update it as described here
The method works, but then I realize that it presents a serious flaw for those who make my job: Winpcap (a packet capture library upon which are based different packet sniffer and network analyzer, such as Wireshark and Windump) “sees” only the packets received by the machine, and not those sent. Disabling the DNE binding on the interface interested in capturing the network traffic solves the problem. This would be a solution, but it does not completely satisfy me.
Afeter some investigation it appears that the Huawei driver appears to the system with two interfaces, one COM emulating a modem and a network interface, which is the mode used by default by the Huawei software, with which I am experiencing the problem.
To definitely solve the issue I created a connection of type Remote, like the old ones used with old serial modems, but connecting to the virtual modem, which in my case is called “HUAWEI Mobile Connect – 3G Modem (COM10).” As the numer to dial, I put *99# (the default number to dial for my Internet provider, Telecom Italy Mobile). I put “tim” as user and password, but I guess anything would work. Et voila, Cisco VPN Client works without changing DNE and the packets are captured again in both directions.

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