[Asterisk-Users] SoftPhones: Bad, or just bad QoS?

[Philipp von Klitzing]

Hi!

> Hi again, folks. I've been getting feedback from this list and  
> elsewhere that softphones are generally not considered good enough  
> for hardcore business use. Can someone point me to where I can find  
> more detail on this debate?

- you comp needs to have its speakers turned on in order to transmit the 
ringing sound; if instead folks use a headset (which they should) then 
the ringing will most likely be directed to the headphones, and if the 
user is not constantly wearing his/her headset the incoming call will go 
un-noticed --> headsets are only good for very frequent callers that wear 
their headset 8 hours/day. If that is so you want to purchase GOOD 
headsets, by the way.

- you very much depend on the quality of the soundcard and the mic; 
misconfiguration of the soundcard mixer or a cheap soundcard with extra 
latency, static, noise from the IDE controller/HDD in the audio etc will 
make your users unhappy resulting in the statement "voip has bad quality"

> Is the problem that the technology isn't mature, that the load on the  
> computer is too high, or simply that it doesn't work well in a poorly  
> designed network?

No, it's not that. However you need to manage the softphone 
configuration, install new releases & bug fixes. Soundcards can sometimes 
introduce echo due to cheap hardware or a bad sound config.

And, probably this is the most important point, everyone knows how to use 
a phone, at least the basic functionality, no need to teach & train 
people on that. With a softphone, however, that is different. And, as 
others have pointed out, it only works when your comp is a) on, b) 
doesn't show a bluescreen, and c) is successfully connected to the 
network.

> Any time I mention VOIP and network, people tell me to make sure that  
> I have QoS capabilities. If I do, and can tweak it appropriately,  
> will that eliminate (or at least greatly minimize) problems with soft  
> phones?

Within your LAN you don't really need QoS if your maximum LAN usage is at 
around 50% of its capacity. On your Internet router QoS can be a good 
thing, though, to make sure that your outgoing VoIP traffic is given 
priority.

> I am really loathe to rewire my building, and I really have to move  
> to gigabit for unrelated reasons, so I would like to be able to use  
> the single gigabit port in every office to serve both the computer  
> and the phone. That seems to mean either soft phones or putting a  
> small gig hub in every office, no?

Except for the recent announcement of 3com to incorporate a Gigabit 
switch into their IP phone you'd have to have a 100 Mbit/s switch in 
every office in order to connect the hardware phones. By the way it 
appears that the 100 Mbit/s switched that are integrated in the hardware 
phones aren't exactly high quality, so if you need a _fast_ link for your 
workstation that don't put it behind a hardware voip phone, even if that 
means more cables.

Your other option is, of course, to keep your old PBX with its phones and 
instead put Asterisk between your PBX and the Internet & Telco. That way 
you save the money for the hardware phones and you have no trouble to 
convince management to spend money on new phones - because you won't. 
Anyway, you should only walk that way if your current PBX can deal with 
digital lines, i.e. PRI (or BRI, which I understand is very uncommon in 
the US where you appear to be located) so that it can be hooked up to 
Asterisk.

Cheers, Philipp