IVR Corner

You can't make this stuff up. Here is a link from a large hosted telephony provider "Ring Central". I found this on their support page, under QOS. This is laughable. Ring Central's model is that customers connect to them via the public Internet. There is no QOS available through any Internet conenction. This means that each of the points they make is either incorrect and irrelevent at best. You see QOS (Quality of Service) defined is the prioritising of some Internet packet streams over others. ie: voice has to travel in a real time stream where as emails can be a half second late. To use QOS on any network, each router and switch would have to be specifically programmed for that particular packet stream. The routers on the public Internet have no such QOS possible as it was not designed to carry real time traffic. This is why any succesful IP voice traffic must be carried over a private IP connection like MPLS, or point to point circuits. Regardless here is one of the pieces of advice Ring Central triess to fool their customers with  
 
"6. Pause any large downloads while on a call. 
 
 
 
You may experience delays or dropped calls if you’re downloading large files over the same network you use to make calls. Your Internet connection may not have enough bandwidth to handle the increased load. Pause any non-essential downloads before making a call." 
 
Can you imagine this? You would have to make a page to your office to tell everyone to get off the internet so you can make a call. You could not even do that because reality is that paging to handsets is one of the list of features that is not supported through a SIP connection due to the fact that the IEEE has no single set of RFC's in common with varying manufacturers. 
 
Check it out for yourself, click on the word "more" under "Improving your QOS" for more misleading advice. 
 
 
 
http://www.ringcentral.com/support/qos-information.html

The scenario described above is presented in such a way that it brings fear into a potential buyer's considerations... and at the same time, there's a bit of "I feel your pain" to those business owners having already made the switch to a IP PBX system. 
 
 
 
Bottom line truth, is that one needs to make very careful analysis of network structure and performance prior to making this change in the office. Know that NO COMPANY has "arrived" at perfecting the engineering of a VoIP / IP PBX system (both hosted and CPE have their good and bad sides).  
 
 
 
There are switch configurations to examine...firewall configurations, network equipment, hardware compatibility, etc. AND there are elements of "you don't know until you know" how a system performs in your network environment...until the system has gone live, and is used in the everyday workflow. 
 
 
 
Bottom line, no doubt its an intimidating process. Best advice I have: Educate yourself, collaborate with experienced engineers, contact references...and talk to current IT staff of companies that have similar systems that you are considering.