When extending your Asterisk IP-PBX to a remote office or other location using analog endpoints, the best solution is to connect to the Grandstream VoIP gateway GXW400x over the Internet cloud. Routes are configured for the IP-PBX to send the call to one of the FXS ports in the VoIP gateway which then rings the analog phone connected to that port establishing the call. Configuration and setup are rather straight forward with a low cost. Some installations, such as warehouse or other such facilities use analog DECT Panasonic phones further offering mobility at the remote location. In some cases where a temporary office requires phone service for a period of time then relocates to another location, these setups are an ideal cost effective solution. A second new device offered by Grandstream is the HT814 analog telephone adapter. The 814 offers 4 FXS ports and has many advanced features that make this device particularly attractive.
Your second location can be any remote office, a separate building or a location even in another country. The IP-PBX uses a VoIP connection to the GXW4000x Gateway. FXS ports allow traditional analog phones to connect. Calls placed to IP-PBX for remote extension (phone) in the remote office are routed through the IP-PBX over the Internet to the GXW4000x VoIP gateway. Analog phone then rings and is answered establishing the call.
Grandstream's new line of HandyTone telephone adapters include the 4 FXS port model, the HT814. Now included are HD voice, dual Gigabit ports and each device acts a s a NAT router, making them ideal for both home use and small remote locations. These devices easily configure when matched with their UCM6202 or UCM6204 IP-PBXs and offer gigabit ports for extra transfer speeds.
Grandstream's GXW400x FXS gateway connected to the Internet behind a firewall links up to the home location's IP-PBX. Inbound calls come to the remote location routed from the home office's IP-PBX and outbound calls go out over VoIP from the gateway back to the IP-PBX and out through their ISTP.
NOTE: By default the GUI of the GXW400x device is disabled and the first thing to do when installing one is to get connected by setting up your IP address and connect with a analog phone connected to an FXS port using a dial/voice menu so you can enable the GUI interface. Press ***, then feature code 12 for the web access menu and use 9 to toggle between enabled and disabled, then reboot.
The following video goes through configuration an settings for Grandstream gateways. Step by step instructions for GXW4004.