The price is as low as $175 per unit.

PX0210 is a DSL MODEM, WI-FI ROUTER, and IP PBX all in one device. This is a featured packed IP PBX for up to 100 extensions with voicemail and capable of making simultaneous calls. This IP Telephone system is a simple and low cost IP based solution for small and medium businesses.                            

VPN

VPN Termination (IPSec)
VPN Termination (PPTP)
IPSec Pass-through
 
PBX Features

Up to 20 Exterior VoIP Lines
Up to 100 Local Registered SIP Clients
Voice Mail for Each Local User
Voice Mail to e-Mail
Interactive Voice Response to Check Voice Mail
Customizable Switchboard
 
Filtering / Access Control

IP Port and Port Range Filtering
MAC Filtering and Tracking
Application Filtering (Single and Range) on LAN
Firewall Logging
LAN Sub-Grouping and Isolation:  Create Isolation between WLAN and Ethernet Ports
802.1x and RADIUS Client
 
CPE Configuration

GUI Interface through Web Browser
SNMP Support
uPnP
Telnet
TFTP
SSH
User Firmware Update through Web Interface
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From:www.vanaccess.com