[asterisk-users] Hardphone SIP phone costs

[Gordon Henderson]

On Fri, 21 Mar 2008, John Faubion wrote:

>> are plenty of phones on the market which do SIP now - most
>> modern Nokias do. I use an E90 Communicator, but the E95 is
>> popular too, so I'm experimenting with using my mobile as my
>> "one" phone, via Wi-Fi/SIP when I'm in the home/office and
>
> Out of curiosity, how do these phones handle the transition from Wi-Fi to
> GSM? Is it seamless? Can the transition occur when on a call?

The ones I've used don't. You make/take a SIP call or a GSM call, but the 
2 don't mix. I can live with that - for now. I have my Nokia set to 
default to making a SIP call, but it falls-back to using the network when 
that fails. (eg. when I go out of range). It goes back to WiFi mode when 
it comes into range of an access point it knows about and I've got Wi-Fi 
search on.

I think there's still some resistance from the (UK) mobile telcos about 
SIP/VoIP on the phones as it's a competing technology, so there were 
reports of early phones being "crippled" by the network operators, but 
there's never been anything to stop you buying an un-branded phone and 
putting your own SIM card in. I think the operators are giving in 
though.... Some even offer free Skype software on the phones and calls 
(but not Skype out!)

Femto cells might be the next best thing though as I'm really not a fan of 
VoIP over Wi-Fi. I'd want one with an Ethernet port and multiple SIP 
accounts, so my mobile could roam to my home/office cell and the cell 
could then either contact my mobile telco, or my VoIP provider, as 
required/desired.

Something like this maybe:
   http://www.3g.co.uk/PR/Feb2007/4221.htm

but a bit more "open" to let you use your own SIP service rather than the 
mobile telcos..

Gordon