Denphone telephone systems can be used in a variety of configurations, including mixed environments of new IP phones and older analogue equipment. In a multi-office installation, the PBX Servers can be linked over the internet to create a virtual global phone network. Also the Servers can be connected to IP phone service providers to add overseas in-bound and out-bound calling in locations where there is no physical office. This is achieved through open standards such as SIP and IAX protocol connections. An example architecture is shown below.

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Denphone Office IP Telephone System

Tokyo

4 x INS64ISDN lines

Example Denphone Inter-Office Call Routing Architecture

New York

Fractional T1

NTTPhone

Network

TelappliantTo UK Phone

Osaka

1 x INS64ISDN lines Laptop with

VoIP software

Trunk line

Hong Kong

POTSanalogue

lines

INTERNET

PCCWPhone

Network

Office LAN

PC withVoIP software

VerizonPhone

Network

FaxIPPhones

Server

Fax Fax

FaxIP

Phones

Server

Office LAN

IP P

hone

Server

Server

Office LAN

IP P

hone

IP P

hone