A company involved in the manufacture and installation of multi-gigabit radio technology base stations was running a 5G mobile network trial sponsored by the Department for Digital, Culture, Media and Sport (DCMS). The out-of-band management of the base stations needs to be over an independent 3G or 4G network and routed back to the company's own private network.
The company chose to use mobile data SIMs from the ISP Andrews & Arnold (AAISP) which can hand over the data connection via an L2TP Tunnel. A FireBrick FB2900 was chosen as the L2TP server (LNS) that the SIMs connect to. Once installed in to the company's private network the FireBrick gives direct access to each of the remote base stations.
Using the FB2900 as a L2TP Server, remote devices are able to connect through in to the FireBrick and then to the internet network.
IPv4 (and in future IPv6) firewall rules are in place to prevent any unauthorised access to or from the remote locations.
The FireBrick uses a number of VLANs on the LAN interface to network with other servers involved in the management and monitoring of the remote base stations.
(All the network diagrams on these case study pages are very rough representations and are not an accurate representation of live networks)