Cordless SIP phone

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Asterisk Users 13 Comments

I have an asterisk box which has Polycom Soundpoints IP335 and IP650s registering to it both locally and remote.

I want to be able to incorporate a cordless phone at the remote location; not a wireless phone.

I want it to also be able to register to the same asterisk box so it can take calls and transfers.

Any idea?


13 thoughts on - Cordless SIP phone

  • What is the difference between a cordless phone and a wireless one?

    We use and recommend the Panasonic KX-TGP500 and 550.

  • To be honest I am not sure.

    I was under the impression that there was a cordless SIP phone that communicated back to the base which was hardwired into the

    Anything like that?

  • Some sort of FXS adaptor (Grandstream HandyTone 286 is still available) and
    a generic cordless phone from any electronics store? You may also need an
    adaptor with an RJ11 plug and whatever phone socket your local telephone
    company use; and in some countries this will need to be a “master” type (with
    bell capacitor), or else the phone may not ring. (A “half-master” type —
    which has the bell capacitor but lacks a surge arrester — will also work

  • I have one of these already installed.

    I have a plain household cordless phone plugged into an SPA which then SIPs back to the server.

    Where I want to put the new on is outside the range.

    I thought SIP cordless phones would be better on the range.

    Either way, does the two mentioned:

    Panasonic KX-TGP500

    Allow to program an extension from the asterisk so it is integrated into the phone system as if it were just another Polycom


  • Yes, the Gigasets can do. You can have up to 3 handsets attached to one
    base station and you can configure it so that each handset can be a
    separate extension or that they call all be the same one.

  • As far as Asterisk is concerned, any SIP phone (even a POTS phone plugged
    into a SIP-FXS adaptor) is a SIP phone (we once had an unholy mix of
    Grandstream, Zultys and another make I can’t remember now on our network).
    You just have to give it an entry in sip.conf with a default context.

  • Yes, that describes the phones I recommended. You can buy one that is a
    base phone with an internal DECT base station plus wireless handsets, or a
    base station alone. Inexpensive and reliable, users seem to really like

    Perhaps you meant one that is not wi-fi? I would agree with that, I have a
    pile of totally useless wi-fi phones, they are all garbage.

  • Yes, both the base phones and wireless handsets have multiple SIP
    registrations that behave just like any other SIP endpoint. Each can work
    independently, even with the base phone being the DECT base. I believe
    that system supports six wireless phones per base, but it might be more,
    check the spec sheet.

  • At 06:35 AM 1/23/2012, you wrote:

    I use Snom M3s. We have one base station and 3 handsets. They work
    fine, but they don’t feel like a business phone. The base is SIP to
    DECT so the wireless quality is good. Range is fine for our small house.


  • Carlos Alvarez writes:

    Ascom has some fantastic Wi-fi phones. They are expensive, but they are
    the only Wi-fi phones I have tried which actually work as phones. They
    manage to get a signal in places where other devices give up, and if
    they lose signal they are quick to regain it when you get closer to the
    access point.

    The cost is a challenge in most installations; DECT often comes out
    cheaper even if you include SIP DECT base stations.


  • In my neck of the woods…

    A “Cordless Phone” refers to a cordless handset with a wired base. The
    phone communicates with the base and can’t work without it. It’s usually
    proprietary in nature as well.

    A “Wireless Phone” usually refers to any phone communicating via 802.11.
    No base required. A cell phone is also sometimes referred to as a
    wireless phone.

  • If you want to extend the range of a DECT basestation you can use
    repeaters, but you then lose DECT encryption and you can only add up to
    6 repeaters around one basestation.

    Extending your range beyond that requires a proper DECT network and
    brings you into a whole new cost level. But that can go up to 256×12
    handsets and 256×8 (IIRC) simultaneous calls…