LANCOM 1722 VoIP – LANCOM 1724 VoIP
Chapter 1: Introduction
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EN
Connecting local ISDN lines with a remote SIP gateway
Companies with nation-wide and internationally distributed sites are often
interconnected with VPN already. A LANCOM VoIP Router can be used not
only to connect the SIP and ISDN telephones at a branch office to the SIP-PBX
at headquarters; it can also integrate local ISDN networks into corporate com-
munications with help of the "SIP Gateway" function.
The SIP gateway is active for outgoing and incoming calls.
A company headquarters in New York can, for example, use a LANCOM
VoIP Router with SIP gateway located at the Los Angeles branch office to
telephone with customers and suppliers located in Los Angeles at local
rates ("local break-out").
For improved availability to customers located abroad, the New York
headquarters can, for example, use a LANCOM VoIP Router with SIP gate-
way located at their sales office in Italy. Customers can then reach support
or service numbers via a standard national telephone number. Calls from
the local ISDN network are received and directed within the company net-
work to the responsible employee. Call routing can be used which identi-
fies the customer's calling number and automatically selects the
appropriate connection to be used for forwarding the call.
Advantages of the SIP gateway:
The local ISDN connection at any site is available for use by any of the
offices throughout the entire company.
National and international long-distance calls can be mapped to local or
regional calls, so saving costs.
LANCOM VoIP
Router
Internet
Local ISDN network
VoIP PBX
VPN tunnel
VoIP telephones
LANCOM
Branch office
Headquarters