Phone/PABX/VOIP Options?
Discussion
I'm in a bit of foreign territory here and would appreciate any advice.
We have a big physical campus and have been asked to look at commissioning offices for a customer. Part of this would encompass telephony.
All I know right now is there would be approx 70 people, I'd assume that means a minimum of 70 numbers required but I have no idea what is needed in terms of "concurrent" connections (if indeed that's how PABX stuff works).
So given that all I know is there may be a need to get a new phone system in a new office on our physical site but that won't touch/access any of our infrastructure whatsoever (beyond the need to run cabling from the main road) where should I begin?
Obviously we have a phone provider that our company deals with, but as this is a completely greenfield install I'm interested in the potential of things like VOIP even if it's at the PBX rather than actual VOIP phones.
I'm sure my terminology is all wrong, but hopefully you get the idea what I'm asking.
Thanks very much.
We have a big physical campus and have been asked to look at commissioning offices for a customer. Part of this would encompass telephony.
All I know right now is there would be approx 70 people, I'd assume that means a minimum of 70 numbers required but I have no idea what is needed in terms of "concurrent" connections (if indeed that's how PABX stuff works).
So given that all I know is there may be a need to get a new phone system in a new office on our physical site but that won't touch/access any of our infrastructure whatsoever (beyond the need to run cabling from the main road) where should I begin?
Obviously we have a phone provider that our company deals with, but as this is a completely greenfield install I'm interested in the potential of things like VOIP even if it's at the PBX rather than actual VOIP phones.
I'm sure my terminology is all wrong, but hopefully you get the idea what I'm asking.
Thanks very much.
http://www.erlang.com/calculator/erlb/
This is a good tool for calculating how many lines you'll need - but it does get quite technical. Happy to take a pm.
There are so many what if's in your original question. Very happy to chat through on the phone if you pm me.
This is a good tool for calculating how many lines you'll need - but it does get quite technical. Happy to take a pm.
There are so many what if's in your original question. Very happy to chat through on the phone if you pm me.
70 people, each wanting their own number, plus sales numbers, reception, fax machines, etc; you'd probably be looking at a 100 DDI block. If they don't all need an external number (members of a sales group, call center bods, or whatever), then you can get away with less.
Maximum number of concurrent connections...this would be how many trunks you have coming in.
This rather depends on how much time each person spends on the phone; a busy call center is going to need a lot more than an average office. So, you need to know what type of business they are.
Then, how much they intend or expect to expand.
Various other things come in to play; how big a voicemail system, do they want an autoattendant system, call queuing, call reporting, call recording, conferencing, twinning calls with mobile phones, etc.
Pretty much any of the mainstream systems can handle pretty much everything you can think of to want...but price can vary enormously depending on the feature set; eg last time I bothered looking Cisco charged extra for the CTU ring tone, and many manufactureres do a standard and enchanced versions depending on what you need. Adding in VoIP or SIP trunks or IP extensions is either an expensive or no cost option; the field varies wildly!
What you need to do is to nail down a feature set that they need, then identify desireable features, and possible future requirements. If you've not done this sort of thing before, looking over manufacturers websites to get an idea of features, and sending out questionaire to the users might be a good idea. Most telecoms sales staff will be happy to go through things with you and help you work stuff out, if you invite them to quote. You've got a provider already, call them up and see what they think - they'd probably be delighted to tender. Most telecomms installers will cover a large range of customer sizes, and these days any extra work is nice to have.
Now, the question I always have at this point is 'why VoIP?'. Then after that, VoIP phones, or trunks? There are pros and cons for both, much as there are for digital trunks and phones. If it's a greenfield site, then adding in the additional cabling for a phone system isn't going to be expensive compared to the cost of QoS switches and configuring and maintaining vlans, for example, so a hybrid PBX with both digital and VoIP/SIP trunks, and digital and alog (and IP) extensions could be a good idea.
In my experience people go fully to IP extensions because either they've reached the cabling capacity of a building, or because they think it's cool, or because they think it'll be cheaper to implement and administer. Unless the IT guys are good, or the customer has the kit already, this last one is rarely the case; when you work out the cost of an IP phone plus any licence keys that might be need, plus the network hardware, plus setup time, plus trouble shooting, it pretty much is the same cost as a traditional digital PBX.
Similar logic applies to IP trunks - great way to save money, but if the provider goes down, or there's an issue somewhere, depending on who it is, it can be a nightmare persuading all the companies involved to resolve the issue.
In this case, without knowing much, I'd vote for a hybrid system with the capacity for SIP trunks and IP extensions if wanted, but have mainly digital phones, and a fractional PRI(maybe a full PRI, depending on load) for the main lines. Add in a SIP trunk later, or alongside in order to help costs.
Of course, as we don't know much about the customer, this could well be utterly inappropriate!
One final point I'd add - when you hear "don't do for ABC system because it's crap, it does XYZ all the time" - take a look at the user groups and forums, and you'll find that they all have their issues. If they didn't, they wouldn't have support staff and I'd be out of a job.
Maximum number of concurrent connections...this would be how many trunks you have coming in.
This rather depends on how much time each person spends on the phone; a busy call center is going to need a lot more than an average office. So, you need to know what type of business they are.
Then, how much they intend or expect to expand.
Various other things come in to play; how big a voicemail system, do they want an autoattendant system, call queuing, call reporting, call recording, conferencing, twinning calls with mobile phones, etc.
Pretty much any of the mainstream systems can handle pretty much everything you can think of to want...but price can vary enormously depending on the feature set; eg last time I bothered looking Cisco charged extra for the CTU ring tone, and many manufactureres do a standard and enchanced versions depending on what you need. Adding in VoIP or SIP trunks or IP extensions is either an expensive or no cost option; the field varies wildly!
What you need to do is to nail down a feature set that they need, then identify desireable features, and possible future requirements. If you've not done this sort of thing before, looking over manufacturers websites to get an idea of features, and sending out questionaire to the users might be a good idea. Most telecoms sales staff will be happy to go through things with you and help you work stuff out, if you invite them to quote. You've got a provider already, call them up and see what they think - they'd probably be delighted to tender. Most telecomms installers will cover a large range of customer sizes, and these days any extra work is nice to have.
Now, the question I always have at this point is 'why VoIP?'. Then after that, VoIP phones, or trunks? There are pros and cons for both, much as there are for digital trunks and phones. If it's a greenfield site, then adding in the additional cabling for a phone system isn't going to be expensive compared to the cost of QoS switches and configuring and maintaining vlans, for example, so a hybrid PBX with both digital and VoIP/SIP trunks, and digital and alog (and IP) extensions could be a good idea.
In my experience people go fully to IP extensions because either they've reached the cabling capacity of a building, or because they think it's cool, or because they think it'll be cheaper to implement and administer. Unless the IT guys are good, or the customer has the kit already, this last one is rarely the case; when you work out the cost of an IP phone plus any licence keys that might be need, plus the network hardware, plus setup time, plus trouble shooting, it pretty much is the same cost as a traditional digital PBX.
Similar logic applies to IP trunks - great way to save money, but if the provider goes down, or there's an issue somewhere, depending on who it is, it can be a nightmare persuading all the companies involved to resolve the issue.
In this case, without knowing much, I'd vote for a hybrid system with the capacity for SIP trunks and IP extensions if wanted, but have mainly digital phones, and a fractional PRI(maybe a full PRI, depending on load) for the main lines. Add in a SIP trunk later, or alongside in order to help costs.
Of course, as we don't know much about the customer, this could well be utterly inappropriate!
One final point I'd add - when you hear "don't do for ABC system because it's crap, it does XYZ all the time" - take a look at the user groups and forums, and you'll find that they all have their issues. If they didn't, they wouldn't have support staff and I'd be out of a job.
I disagree, it's a greenfield site so go VoIP internally from day 1. But make sure that you have the networking guys design for internal telecoms over the network (inline power in your switches etc).
Any decent system should be able to cope with any type of inbound traffic be it pstn/isdn, sip etc.
Most of the systems I work on still use isdn30 to deliver the majority of their external traffic. Depending on how critical you telecoms are these are then deliverd via diverse routes and diverse suppliers. A new customer is putting SIP trunks in, for a call centre with 1000 seats that's a brave choice!
I would advise engaging a specialist sub-contractor to design and build the telecoms.
Any decent system should be able to cope with any type of inbound traffic be it pstn/isdn, sip etc.
Most of the systems I work on still use isdn30 to deliver the majority of their external traffic. Depending on how critical you telecoms are these are then deliverd via diverse routes and diverse suppliers. A new customer is putting SIP trunks in, for a call centre with 1000 seats that's a brave choice!
I would advise engaging a specialist sub-contractor to design and build the telecoms.
I'd certainly go the voip route, with a solid network underneath it.
We've done a lot of work recently putting voip/sip systems in. using a virtual switch for each customer on the servers in docklands..
really handy if you've got staff on the road or home workers as well. simply give them a soft phone, of take the unit off the desk, plug it into the internet anywhere and bingo your extensions plugged in and working..
I even took one to florida on holiday with me. The villa had broad band, I plugged my phone into it, and it was just as if i was in the office in the uk... had to remember not to use it to make usa calls though !!
Cheers
Graham
We've done a lot of work recently putting voip/sip systems in. using a virtual switch for each customer on the servers in docklands..
really handy if you've got staff on the road or home workers as well. simply give them a soft phone, of take the unit off the desk, plug it into the internet anywhere and bingo your extensions plugged in and working..
I even took one to florida on holiday with me. The villa had broad band, I plugged my phone into it, and it was just as if i was in the office in the uk... had to remember not to use it to make usa calls though !!
Cheers
Graham
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