Hosted IP Centrex solutions

Since Centrex frees the customer from the costs and responsibilities of major equipment ownership, it can be thought of as an outsourcing solution. The evolution of this service has led to IP Centrex (Internet Protocol Central Office Exchange).

IP Centrex builds on the traditional benefits of Centrex by combining them with the benefits of IP telephony. One of the benefits of IP telephony is the increased utilisation of access capacity. In IP Centrex, a single broadband access facility is used to carry voice streams for many simultaneous calls. In addition, IP Centrex provides a lot of features not previously available with traditional Centrex solutions.

In essence, IP Centrex solutions offer the same services as provided before by Centrex solutions, but with a lot more flexibility due to the nature of SIP (session initiated protocol).

It is common knowledge that local broadband rates are still overpriced compared to other countries in the world. Even so, the demand for broadband continues. The latest figures from Telkom show the ADSL subscriber base has increased from last year by 33%.

While ADSL might not be the technology of choice for IP Centrex solutions due to the up and down streams of data on ADSL not being similar, it represents a good indication of the need for data access in the market.

I don't believe the cost of broadband is an inhibiter for IP Centrex services. Yes, inexpensive broadband services would go a long way to creating a favourable environment for hosted IP Centrex services, but the reality is that micro, small, medium and large enterprises have and are investing in broadband services to allow for efficient data connectivity.

Their investments are first and foremost made to allow them to connect data. IP Centrex solutions will provide businesses with future ROI on their existing data network.

In SA, more than a million companies of various sizes are registered: all of which are experiencing an increase in mobility and data connectivity of workers. Knowledge is power; and for the modern business, to be connected or visible via the Internet has become a necessity, especially for businesses focusing on information sharing and business-to-business segments. This means efficiencies in business are driven by data connectivity.

In most cases, companies have already invested heavily in data connection services. The associated costs of these services, in most cases, can be classified as fixed expenses, and companies are already utilising these fixed expenses to make voice calls between different internal branches. SIP trunking is therefore not something new; it is already been used very successfully within organisations. Therefore, the technology to connect SIP voice to the outside world is already in place, SIP trunks need only be connected to the outside world instead of just connecting different branches within the same organisation.

It is common knowledge that local broadband rates are still overpriced compared to other countries in the world.

Hercules Schoombee is MD of Aastra Telecom SA.

Normally, SIP trunking is interconnected between the different branches with a virtual private network (VPN). The main reason for using a VPN is that if a call is set up within the VPN, encryption is provided. Additionally, most companies sub-divide their local area network into virtual local area networks (VLANs). The reason for using VLANs is voice packets can be prioritised (voice is a real-time application) over data, and additional bandwidth could also be exclusively allocated for voice.

Hosted IP Centrex providers will also need to provide for similar services, since the biggest challenge in South Africa is that most cost-effective broadband services provide best effort services. Additionally, these vendors will need to consider issues like quality of service, call admission control and denial of service requirements typically associated with a telco's type of organisation.

I believe the real players that will provide these services are aware of the challenges at hand. Due to business requirements, people are already connected to the Internet; I believe the first challenge of being connected has already to some extent been addressed. A springboard has been created for hosted IP Centrex solutions to be rolled out.

The only other requirement is for the VOIP provider to have termination agreements in place with other ISPs or telcos to terminate calls on their respective networks. VOIP providers in SA have interconnect agreements in place with Telkom, MTN, Cell C and Vodacom, as well as agreements in place to terminate calls on international networks.

I believe the technology platform to roll out IP Centrex solutions is already in place to a large degree, and South Africa is closer to having hosted IP Centrex solutions than people actually realise.

* Hercules Schoombee is MD of Aastra Telecom SA.