Configuring GSM VoIP gateways with Cisco Call Manager

Released on = August 4, 2005, 7:44 am

Press Release Author = Nicole Konstantinidisova

Industry = Telecommunications

Press Release Summary = The present document is a step-by-step guide for configuring the GSM VoIP gateways 2N VoiceBlue Lite (VBL), 2N VoiceBlue Enterprise (VBE) and Cisco Call Manager (CCM) software IP PBX. It includes essential steps for interconnecting the two products rather than a detailed configuration analysis of all units.

Press Release Body = What is 2N VoiceBlue?

The 2N VoiceBlue GSM VoIP gateway is an ideal complementary product to any SIP-based IP PBX. It's suitable for small and medium companies with IP infrastructure and for companies with international affiliates. With VoiceBlue you gain significant savings on outgoing and incoming calls from IP to GSM networks and backwards. Thanks to the efficient and powerful Least Cost Router (LCR), the VoiceBlue VoIP GSM gateway always chooses the cheapest possible way to route the call (according to GSM prefixes, free minutes on SIM cards etc.).Using the VoiceBlue GSM VoIP gateway you
achieve complete independence when connecting to GSM networks and maintain 100% control of your GSM call costs. With the help of voice prompts and efficient Dynamic Clip Routing, the VoiceBlue fixed cellular terminal routes incoming GSM calls to the right IP phones.

What is 2N VoiceBlue Enterprise?

2N VoiceBlue Enterprise is a VoIP to GSM Gateway supporting SIP and H.323 at the same time. It is a complementary product to any SIP or H.323 based IP PBX and can also be used as a substitute to any SIP based IP PBX because the SIP proxy server can be included. The VoiceBlue Enterprise fixed cellular terminal can be used not only as a gateway to GSM but also a protocol translator between the SIP and H.323 environments (the scheme below). As VoiceBlue Enterprise VoIP GSM gateway uses the Siemens MC75
module, it is capable of data transfer (GPRS and EDGE technologies are implemented) and therefore can serve as a gateway from your LAN to the Internet. A firewall is embedded to provide maximum security. There is an option of SMS sending and receiving through a web or SMTP/POP3 interface. If an external USB hard disc is added, VoiceBlue GSM router can serve as an SMS server for SMEs as well.

Our scenario

In this article we are going to deal with configuring VoIP GSM gateways and Cisco Call Manager system, connected in the way this scheme can resemble the practical application in the best possible way. Let’s imagine a company using CCM as the main exchange in its headquarters in the Czech Republic and having one branch office in UK. Together with CCM, there is 2N
VoiceBlue GSM VoIP gateway installed in the company headquarters, which will be used to complete calls to local GSM network.

The branch office in UK is so small it does not pay off to equip it with the
classical exchange and most of its employees are out of their offices most of the time. This implies that most of the communication between the headquarters and the branch office employees will be performed over mobile phones in the UK GSM network. For that reason the VoiceBlue Enterprise VoIP system can be installed instead of branch office exchange, will ensure PBX functions for employees and at the same time the connection to GSM network, together with SIP telephones located in the UK branch
office. Thanks to the Internet connection of the headquarters and the branch office the calls between companies can be routed free of charge and calls to distant GSM networks can be charged locally. (To make it simple let’s suppose there is an IP VPN created between the headquarters and the branch office so the whole operation will function in a transparent way.)

Now we have the scenario, but the question is what part individual elements in our model will play. First an internal numbering plan has to be created. To make it simple let’s say, we will use four-digit numbering and all telephone numbers in the headquarters will start with 1XXX and all telephone numbers in the branch office will then be numbers starting with 2XXX. Furthermore let’s say that all calls to numbers with prefixes 004206,004207,004208,6,7,8 will be routed to VBE IP address in
the company headquarters, all calls starting with 00420 will be routed to CCM and calls with 0044 will be routed to VoiceBlue Enterprise. This way it is ensured that if somebody in the branch office calls the Czech number, the VoiceBlue Enterprise GSM VoIP gateway will send the call to CCM and vice versa.

For rest information visit 2N web page: http://www.2n.cz/news/press_releases/configuring_voiceblue_with_ccm.html

Web Site = http://www.2n.cz

Contact Details = Nicole Konstantinidisova
Modranska 621
Praha 4
Czech Republic
tel: +420 2 613 01 515
fax: +420 2 613 01 599