Interestingly, Cisco already has a platform that will do all of this and more for the smaller business. It's the Cisco Unified Communications 500 Series. The basic solution includes telephony support for 8 IP phones, 4 FXS analog phones and 4 FXO analog trunk lines, plus support for SIP trunking. It has integrated voicemail and an auto-attendant, making it a full-featured small office PBX phone system.
So far this sounds like a typical small office IP PBX system. But the 500 series platform goes further. The antenna implies wireless communications. In this case it's an 802.11b/g wireless access point that supports wireless LAN IP phones as well as wireless data devices.
Connection to the WAN or Wide Area Network gives you broadband Internet access with full security via a Cisco IOS Firewall that supports point to point VPNs. Use these Virtual Private Network connections to include home workers or employees operating remotely. You can also easily expand LAN access inside the office by adding a Cisco Catalyst Express 520 Switch with 8 additional ports of 10/100 Mbps PoE (Power over Ethernet). This switch comes configured to work immediately with the 500 series.
With this system, called the Cisco Smart Business Communications System, you have up to 16 computer workstations, IP security cameras, or IP phone sets, a data/voice wireless access point, secure WAN (broadband Internet) access, secure VPN communications to remote locations, an in-house telephone system that connects to the PSTN and supports FAX machines and other analog devices, plus simplified set-up and management built-in. It's a single box that supports the complete small office communications needs.
