Iñaki Baz Castillo wrote:
> El Jueves, 11 de Junio de 2009, Paul Kyzivat escribió:
>> In one case I have a single phone with one phone number. Typically if a
>> 2nd call comes in while phone is in use it is signaled to the callee in
>> the media stream rather than through "ring". To switch between calls you
>> typically use "flash". This is case where typically the caller might get
>> a "call waiting" signal. (Because this case is considered a "call
>> waiting" feature.)
>>
>> A 2nd case is where I have a "desk phone" with multiple "line" buttons
>> on it. Those "lines" may be associated with distinct phone numbers. By
>> pushing the line buttons you can connect the microphone and speaker to
>> one or the other of the "lines". While a call is in place on one line, a
>> call may come in on the other "line". Typically the signaling in this
>> case would still be a ring, or maybe a flashing of the light on the line
>> button, or both. To switch and answer the 2nd call you might have to
>> first push HOLD and then press the button for the other line. In this
>> case, AFAIK, the caller is *not* likely to get a "call waiting" signal.
>
> For the caller signalling perspective both mean the same: the callee is on a
> call but has notification of this new call.
>
>
>> The above are "traditional" renderings of a couple of different
>> services. But fundamentally they are almost the same. In particular, the
>> increased effort and delay to answer the 2nd call is pretty much the
>> same in both cases. So if it makes sense to alert the caller to this in
>> one case, it ought to make sense to do so in the other case too.
>
> I agree, it's exactly the same (jsut different technology but some concept).
OK. We are in violent agreement.
Its just "common practice" that doesn't agree!
>> OTOH, I am not convinced that it makes sense in either case. Being "on
>> the phone" at least means you are *near* the phone. So the time to
>> answer may actually be less, on average, than when you are not on the
>> phone. So what is the point in signaling anything special?
>
> If I call somebody (my boss) and receive "Call-Waiting in remote side"
> indication, I could hang-up inmediatelly and call later (this is really
> useful
> in case my call is not urgent at all and I don't want to disturb my boss who
> could be on an important call).
You could. Of course in the meantime he might have already initiated the
answer to your call, and so might be even more disturbed. :-)
>> If anything, it would be better if the callee could cause a signal to be
>> returned to the caller that affirmatively indicated "I acknowledge your
>> call, but will need extra time before I can answer it".
>
> The Call-Waiting indication in the response could be generated in varios ways
> by the callee:
> - Automatically when an active line already exists.
> - Never.
> - Manually by pressing a button (notify call-waiting to caller).
>
> These options could be configurable in the phone.
Yup!
> So, if we consider 182 valid for this purpose (and I think we all agree) then
> this feature would require:
> - UAC implementation (display "The remote is actually on a call" upon receipt
> of 182).
> - UAS implemetation (with the options I mention above).
>
> Do yo agree?
Pretty much. The 182 has a somewhat vague meaning, and it think it is
fine that the meaning be that way. The implementation should be able to
display whatever it wants - preferably something in line with the vague
notion of 182 or it can choose to assume what it thinks is the most
common usage and call it that.
So it might display or say:
- the remote is actually on a call
- the callee is occupied but will answer you eventually
- your call is waiting for the called party to answer
- your call has been queued until answered
- ...
- any of the above in Spanish :-)
Or it might just play a distinctive ringback tone. (Maybe that little
tune they play on Jepardy while waiting for contestants to answer.) (Do
you know Jepardy TV show where you are?)
Its not really essential that all phones do the same thing, any more
than it is that all phones have the same ring tone.
Paul
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