Dolphin Promotions have been using VOIP for quite a while and we have loved it, and it is an option many businesses are moving into. It is also a solution that many people seem to tout as a miracle solution for businesses due to flexibility and reduced costs. However it is not always as simple as moving over to VOIP and all your problems will be solved.

I have known many friends with small companies rush into a VOIP solution without much investigation into it. One of the main areas I find people need to read about is the particular type of solution you require, I have known many people invest into a Skype number or similar solution which provides very cheap calls and is great for a home user, however for a Business you can be limited to the scalability of this solution (though this is slightly inaccurate as it is possible to set up a PBX on skype). What happens if your business grows and you start to employ more than a couple of people is your Skype system cut out for this?

When we implemented our VOIP solution we decided that a hosted VOIP PBX would be the best solution this allows us to run a very advanced phone system that could cost hundreds if not thousands through traditional PSTN setups.
For those of you out there not in the know a PBX (Private Branch Exchange) performs three main duties
1. Establishing connections (circuits) between the telephone sets of two users. (e.g. mapping a dialed number to a physical phone, ensuring the phone isn’t already busy)

2. Maintaining such connections as long as the users require them. (i.e. channeling voice signals between the users)

3. Providing information for accounting purposes (e.g. metering calls)

In addition to these basic functions, PBXs offer many other calling features and capabilities, with different manufacturers providing different features in an effort to differentiate their products. Common capabilities include (manufacturers may have a different name for each capability):

* Auto attendant
* Auto dialing
* Automatic call distributor
* Automated directory services (where callers can be routed to a given employee by keying or speaking the letters of the employee’s name)
* Automatic ring back
* Call accounting
* Call forwarding on absence
* Call forwarding on busy
* Call park
* Call pick-up
* Call transfer
* Call waiting
* Camp-on
* Conference call
* Custom greetings
* Customised Abbreviated dialing (Speed Dialing)
* Direct Inward Dialing
* Direct Inward System Access (DISA) (the ability to access internal features from an outside telephone line)
* Do not disturb (DND)
* Follow-me
* Interactive voice response
* Music on hold
* Night service
* Shared message boxes (where a department can have a shared voicemail box)
* Voice mail
* Voice message broadcasting
* Voice paging (PA system)
* Welcome Message
The system is cheap enough that the monthly cost is negligible to our income while we are still relatively small but it is also scalable enough that we could easily triple in size without having to make many changes to the system. For each member of staff needed in theory all we need to do is buy a new sip phone (or use a soft phone if money is an issue) and add a new extension to our account.
VOIP has some huge disadvantages compared to traditional PSTN phone lines and the larger a company becomes the more serious these issues are.
The issues in order of severity (in my opinion) are:
1. Call Quality
This is certainly an area VOIP gets a lot of bad press for; many people perceive that the call quality is less than a PSTN phone system. This is not actually the case but it does depend what codec you use for the calls. The codec codes and decodes an analougue signal and the encoded signal can vary in size depending on the quality of the codec.
The G711a Codec is a very high quality codec which will deliver CD audio quality, this is actually much better than an ordinary telephone call.
GSM is the codec used in mobile phones and therefore will provide the same quality.
The problem with quality occurs due to the issues with bandwidth with the broadband implemented in a business. In the UK most people use ADSL lines which are either 2Mb or 8mb, the problem is that this is asymmetric and while a user may get 8Mb downstream most ADSL connections provide 256kbs upstream. The G711a codec uses 90kbs for its transition and the GSM uses around 14kbs. Therefore on an ADSL line that is used for nothing else a typical user will be able to handle 3 simultaneous phone calls on the G711a codec or 13 on GSM. If you then take into account general internet use this number could be greatly reduced and this is where call quality will drop or even worse entire phone conversations will be cut off.

2. Network Failure
The other large issue with VOIP is that it is totally dependent on your internet connection and therefore if you net goes down so does your phone. A traditional phone line rarely goes down, even in brown out phone lines can still stay up. If you use a Hosted PBX then this issue is also the case at your VOIP provider therefore you have 2 possible places of total telephony failure.
3. Service Provider

This is somewhat tied into the previous 2 points. Your phone system is completely dependant on both your VOIP provider and your ISP maintaining the quality of service. If your telephone system is important to your business do not just buy the cheapest Broadband or the cheapest VOIP provider, you most likely will have issues with the system. The worst case scenario with VOIP providers is that they go bankrupt for whatever reason and this could quite likely lead you to losing you main telephone number and/or being without a phone system for a long period of time.
4. Emergency Calls
Obviously 999 calls are very important however many Voip providers now allow this, also most people will have some form of traditional phone line on premises so making 999 calls should not be a problem for most. However it is worth taking into consideration if your company is larger than just a few people. I am not clued up on this law but I assume it is a legal requirement that staff must have some form of access to emergency services.

The first 3 points may put many people off a VOIP solution however careful implementation should allow you to overcome these issues.
For call quality makes sure you:
1. Implement a good ADSL or SDL line, the faster upstream the better. Bethere offer packages that can have up to 1.3 Mbs and even 2.5mbs upstream.
2. Monitor the internet use, if your work uses the internet heavily have separate ADSL lines for phone and internet use*
3. As you increase in size and if mobile phone call quality is acceptable use the GSM Codec.
For Network Failure
1. Ensure both your ISP and VOIP provider have good customer service, and offer excellent uptime. We have used Voxhub and Voipfone for Voip and neither have had system downtimes that I am aware of. We use Bethere fore ADSL and have had 1 downtime in 9 months.
2. Find a VOIP provider that can offer a PSTN failover. Voipfone can divert calls to a traditional landline in the event of network failure on our end and to some extent on their end. While this is not ideal it ensures our clients can always contact us.

*This is relatively easy to implement, obviously if your company is quite small and the network is quite simplistic you can literally just plug the phones into one adsl router and computers into the other. On larger network installations you could run the PBX and Internet connection over a single LAN but with multiple ADSL lines using the following setup:

ADSL PBX Network Installation

Click image for full size



If you are wishing to sign up to a Hosted Voip PBX we would recommend Voip Fone who offer many featurs with there sytem and are competatively priced. The first person to sign up can go here following registration and use this refer code: MIJPINN. This will give you (and myself) a months free services from Voip Fone