NUREMBERG. Funkwerk Enterprise Communications GmbH, a subsidiary of Funkwerk AG, is presenting with the VoIP-VPN gateway module the ideal supplement to the elmeg ICT systems. The module combines modern Internet telephony by Voice over IP with secure data exchange, together with branch networking over VPN. There are two integrated slots for the M 4 DSP and M 8 DSP expansion modules. These upgrade the VoIP-VPN Gateway with digital high compression voice channels for the crossover to the fixed line network. The new VoIP-VPN gateway can also be used compatibly in older elmeg ICT systems.

VoIP has now emerged from the development phase and is in many cases a real alternative to classical fixed line network telephony. Internet telephony has high cost-saving potential and simplifies administration by bringing together voice and data networks. Particularly interesting in this connection are the modular PABX systems of the elmeg ICT series. These allow VoIP to be integrated into the company network using cost-effective scalable modules. In this way, an effective VoIP platform is created which offers full functionality with a secure future at low investment costs for small to medium sized businesses.

VoIP-VPN Gateway for Connections to the Internet

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The telephone and data networks use different protocols and transmission paths. The gateway between the two worlds therefore acquires vital significance. The elmeg VoIP-VPN gateway module supports all important network protocols such as ARP, IP, DHCP, DNS PPtP and PPPoE. An elmeg ICT system that is equipped with the VoIP-VPN gateway can provide all the basic network services and thus becomes the ICT communications hub. The system then functions as a DHCP server, allocates IP addresses to all computers in the network, and points to the correct DNS server and Internet gateways. The ICT system also provides the Internet access itself. Configuring the Internet access is made very simple with pre-prepared selection lists of the most common providers. Where access to the Internet is over ISDN, the elmeg ICT system takes care of keeping charges to a minimum. Connections are broken off automatically after a configurable period when no data is transmitted. Security, a very important topic in the age of viruses, worms and operating system vulnerabilities, is also treated seriously by the VoIP-VPN gateway. A Stateful Inspection Firewall blocks unauthorised accesses from outside and only permits connections that the administrator explicitly approves using user-defined filters. Pre-configured filters for different client/server applications facilitate this task and ensure that all necessary Internet services are given free access to the web.

Secure Internet telephony with VPN

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The SIP standard has become established in the VoIP area for communication between telephones and gateways. The elmeg VoIP-VPN gateway also supports SIP, in order to address standard IP telephones in the local network. The VoIP module also permits encrypted speech communication over IP, for example when a branch office of the company is connected to the elmeg ICT system over the Internet. A VPN connection between the locations or directly between the IP telephone and the elmeg ICT system is used then. This encrypts the call securely against interception, while the user remains unaware of this additional security measure. The elmeg IP-S290 and elmeg IP-S400 system telephones, available from quarter 03/2005, can be connected directly to the VoIP-VPN gateway and offer the accustomed system convenience in addition to the standard applications. In order to integrate speech communication into the system as cost-effectively as possible, login to any SIP carrier and SIP provider is possible. The most cost-effective supplier is automatically selected by integration into LCR (Least Cost Routing) Professional.

DSP Modules for Crossover to the Fixed Line Network

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While a VoIP gateway only permits communication between pure IP telephones, the M 4 DSP and M 8 DSP expansion modules transform the module into a complete fixed line network to IP gateway. This also makes it possible to transfer IP voice data to the traditional voice network and vice versa. In order to obtain optimum voice quality with the lowest possible bandwidth, the common voice codes G.711, G.723.1, G.726 and G.729a/b are supported. With the combination of an elmeg ICT system, the VoIP-VPN gateway and one or two DSP modules, any traditional terminal device, whether analogue or ISDN, and any IP telephone can make use of IP voice telephony. Depending on the level of expansion, up to 16 simultaneous IP-fixed line network connections are possible using two 8 DSP modules.