What modem I shuld use to connect PSTN line to my network??

Posted on 2011-04-22
Last Modified: 2012-06-21
Dear EE

I have tow Office

Green Office - Head Office
Red Office - Branch Office


in green office I have more than 12 PSTN line I used 10 line for the green office, the branch (Red office) the don't have any connection except WiMax Point to point Network .
its impossible to pull another cable for red office because geographic problems, and permitting procedures.  

To use the same network design for both network and telephone line using additional modem or router..
they need to be tow line from PSTN for tow deference users.
the phone should be analog-set for tow users they can use it as direct lines without any connection for BPX or IP Telephony.

what is the modem or router should be used ?
what is the configuration if its required?

you can see the image below to understand more about the problem .
for more information just post .
Question by:AymanDasa
    LVL 13

    Expert Comment

    this is almost the same question you asked:

    What problem are you trying to solve?

    Author Comment

    Dear kdearing

    its NOT same

    we have wireless between, point to point.
    If you have solution please help.
    LVL 15

    Expert Comment

    Im not sure  i understand the question.
    I think you want two lines sent over voip to a remote office.
    How much do you want to spend?
    How important is phone quality?
    Do you have QOS enabled?
    Do the users have to call out on the same number every time or just receive calls on the same number?
    Is this going to be configured for all users or just the two in the remote office?
    Are there any other features you require/are considering ie huntgroups, call pickup voicemail..

    LVL 42

    Accepted Solution

    Your question has a misleading word in that you ask for a modem when what you want are a pair of FXO and FXS analog gateways.  The FXO box connects to the actual PSTN telephone lines and the FXS box connects to the telephones/fax machines, etc.
    What you want is one each of the Grandstream GXW4104 and GXW4004 which will handle 4 PSTN lines over your wireless ethernet connection.
    Grandstream product page:

    Author Closing Comment

    that what i need . THANKS

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