Hunt Groups / work groups

[EpoUser08]

We have not installed a shoretel yet, but are just about to.

The fact that you can only have a maximum of 16 extensions in hunt groups on a switch is seriously restrictive.

I appreciate that there are work groups, but this will use up WAN resource if the call comes into a remote site from where the HQ server is located.

Can anyone advise how long and how many channels will be open across the WAN when a call comes into a shoregear via the PSTN on site B, and needs to use a work group because there is just not enough resource on hunt groups, and the HQ server is on site A.

Presumably if we have set a limit of the number of concurrent calls allowed across the WAN, and we are at capacity, the workgroup will not function?

 

[EddieVenus]

Hunt groups would not work any differently in regards to WAN useage. So I guess I am not sure what the problem is here.

A hunt group is just a stripped down version of a workgroup, all the same functions are available to a workgroup as it is in a hunt group (but not the other way around).

IP does not use 'channels' like TDM does. It uses bandwidth, which is similar in ways but certainly not the same as channels. So a WAN call, assuming the standard G.711 codec, is 64Kbps of payload, plus IP overhead, plus encryption if it is a VPN. So on a standard WAN link (a point to point T1, or an MPLS circuit, etc) it would be around 82Kbps worth of bandwidth per call. Cisco has a cool little app that calculates this all out for you, you need a CCO account to use it, but if you have it just search for voip bandwidth calculator.

So every call is roughly 82Kbps per call. This only uses bandwidth PER CALL, not per user. So regardless of how many users are in the hunt group or work group the only bandwidth used is the bandwidth needed for that call. Using other codecs can help, such as G.729 or ADPCM. Those will decreast the bandwidth useage by around half or more, but come at a cost. They do compression thus potentially affecting quality though in my experience no one ever really notices, some say they do but I have done blind testing with some of these people and found they are wrong just as often as they are right about if it is compressed. However there is a cost in delay, which is only a problem for connections around the world really.

So I hope some of this info helps, but I suggest you take the ShoreTel 4 day class, which goes over all of this to some degree. Though you will not be an expert after that class you will at least know the answers to questions like the one you posed here.