Tech Troubles

In general VoIP requires a stable connectivity line to stop voice jittering due to packet loss or delays in speech. Data usage such as internet browsing, email and video streaming on the same line is not advised unless a VLAN is used. A VLAN takes a portion of the connection and blocks it off purely for VoIP, so no data can interfere with the VoIP traffic. Not all connectivity providers can/will provision VLAN’s.

A general rule of thumb for VoIP to work well with good to excellent voice quality is to use:

1. A dedicated line if the connectivity line is a broadband service such as:
   • ADSL (currently end-of-life)
   • Mobile Wireless (3G and LTE)
   • Point-to-multipoint or Unlicensed Fixed Wireless / Microwave services.
2. For guaranteed connectivity services a single line can be used for VoIP and Data provided that a VLAN is provisioned to carry the VoIP traffic. Services that a VLAN can be provisioned on include:
   • Business Broadband fibre (certain providers)
   • Licensed spectrum point-to-point Fixed Wireless / Microwave services
   • Guaranteed Business Fibre (Layer 2 and Layer 3 services)
3. For larger guaranteed connectivity services like Guaranteed Business Fibre, clients can use a single line for both VoIP and Data without a VLAN, but that is determined on a case-by-case basis, and a VLAN is generally advised for VoIP
4. A dedicated line of a guaranteed connectivity service for larger sites to be used only for VoIP. This is usually 50+ concurrent calls.

VoIP uses approximately 100Kbps for 1 VoIP call. A breakdown of recommended connection speeds per concurrent calls is seen below:

Centracom are experts in advising and assisting clients in choosing and setting up the right connectivity for VoIP and Data at the business location. Centracom has direct API and mapping access, via its sister company Pindrop, to over 50 connectivity providers in South Africa.

You will need a VoIP provider, a stable interconnect connection, and depending on your office setup, you may need some additional hardware to enable VoIP to work. Centracom also recommends a ViBE or L2TP router to secure calls to stop hacking and improve quality.

1. For businesses with IP Phones that are SIP enabled, you will just need the SIP account details from your VoIP provider.
2. For businesses with TDM PBX’s, a VoIP gateway will be required and a SIP trunk from your VoIP provider.
3. For businesses with an IP PBX you just need a SIP trunk from your VoIP provider.
4. For Hosted PBX clients, VoIP is native to the setup so you will just need a solid internet connection.

Yes, VoIP can be integrated to old TDM PBX’s and newer IP PBX’s and is core to Hosted PBX environments.

Private Branch Exchange (PBX) hardware has traditionally been used by large enterprises that need a lot of phone lines and thus opt to host their own phone systems locally. A PBX system physically switches calls between enterprise users on to various local phone lines while permitting all users to share a single (or sometimes multiple) external phone lines. Historically, enterprises installed local PBX systems to reduce the cost of subscribing to multiple telephone lines for each employee.

Essentially, a PBX system connects internal phones within an enterprise to either the PSTN (Telkom) or a VoIP provider via Internet (Centracom). The setup will change depending on whether it is a traditional TDM PBX system or an IP PBX system.

Traditional PBX’s called TDM PBX’s use analog signals and natively connect to PSTN’s. In order for TDM PBX’s to use VoIP, analog signals need to be converted to digital signals. A VoIP gateway is a hardware device that converts analog traffic into packets of data for transmission over the internet and allows TDM PBX’s to connect to VoIP providers.

Newer systems referred to as IP PBX’s use digital signals and break out over the internet via a SIP trunk provided by VoIP provider. If an enterprise opts to break out to a PSTN then the digital signals need to be converted to analog signals via a special card purchased from the PBX vendor.

Centracom connects to all types of PBX’s through VoIP gateways and/or providing SIP trunking to existing environments. Centracom offers Cloudcall Hosted PBX which is one of the most advanced systems in South Africa.

VoIP companies today implement several technologies to secure their service from the client’s premises to the VoIP network via 128bit encryption.

Algorithms on call usage are implemented to monitor usage patterns per client with the intention of cutting suspicious calls as or before they happen.

The main security threat VoIP customers face is hacking. This happens when a customer’s hardware on site is hacked, and calls are made on the customer’s account illegally. Usually, these calls are to a premium service number (such as a daily horoscope) where the service is based in another country where the laws that govern this practice undeveloped. Whilst the service is technically legal, the revenue share on the back of these premium services is with the hackers who illegally initiate millions of calls to the number to generate illegal revenue. As the hack is mostly anonymous and the call technically done legally, it is hard to prove a hack and there is very little a VoIP company can do once a hack has taken place. Good VoIP networks stop hacks before they happen or respond immediately when something appears wrong.

Centracom uses L2TP and ViBE with 128bit encryption technologies and advanced algorithms to block suspicious calls made to either geo-blocked areas such are Sub-Saharan Africa, calls made outside of business hours, or calls with irregular dialling patterns such as repetitive call initiation and termination to a number.

VoIP is by far cheaper than a landline services. PSTN providers such as Telkom charge high rates for calls, and because of this an entire VoIP industry was born as the VoIP providers use IP technology to carry the same calls far more cheaply. Estimates on call savings range from 25% – 55% depending on the mix of calls for a particular client.

Usually, the greatest call saving is seen on mobile calls (Vodacom / MTN and Cell C / Telkom Mobile), then landline calls (geographic and non-geographic landlines), special service numbers (0800 and 0860), and finally international calls.

VoIP providers can bill per second which further increases call savings.
If you were to combine a VoIP service with a Hosted PBX solution to replace your onsite PBX, you can drastically decrease your capital outlay and/or monthly hardware rental costs. Hosted PBX setups only use VoIP to carry the calls.

Centracom saves its clients on average 20% – 30% on mobile calls, 10% – 20% on landline calls, and up to 50% on international calls (destination dependent).

The call quality of a VoIP systems depends on the speed and reliability of a customer’s internet, as well as the quality across the VoIP providers’ network. Customer’s end user device (IP phone) plays a part with modern-day devices such as Yealink IP phones enabling HD voice quality, allowing VoIP to outperform PSTN / landline (Telkom) voice quality considerably.

When listening to VoIP compared to traditional phone lines, you will hear a vast improvement in call quality compared to traditional landlines. Landlines don’t have as much audio bandwidth, which can result in muffled or fuzzy calls. VoIP calls achieve far greater clarity through HD voice technology. The number of HD Voice calls you can handle will depend on how fast your internet download and upload speed is.

The Mean Opinion Score (MOS) was initially developed to measure traditional calls and has been extended to measure calls on VoIP networks. MOS score is a rating from 1 to 5 of the perceived quality of a voice call – 1 being the lowest score and 5 the highest for excellent quality.

VoIP calls are split into subcategories based on the VoIP codec used (ex: G.711, G.722, G.723.1, G.729). Some codecs such as G.711 are uncompressed for higher quality but use more bandwidth than compressed codecs such as the G.729.

The MOS score the industry measures is the G.711 codec, which is by far the most commonly used codec for VoIP networks and is the codec that Centracom uses. The maximum MOS for a G.711 VoIP call is 4.4. Centracom has a MOS rating of 4.2 / 5 which is deemed good to excellent call quality.

Centracom utilizes Pindrop, a market leader in connectivity feasibilities, quoting and connectivity project management with over 50 connectivity providers mapped in to their database. This enables Centracom to instantly quote on DSL, Business Fibre, LTE and Wireless, giving Centracom one of the most complete voice and data offerings in South Africa.

VoIP call costs in South Africa are made up of the Interconnect rate set by ICASA plus the providers mark up. The most watched interconnect rate is the mobile interconnect rate.

The interconnect rate is the regulated amount providers are allowed to charge each other for a call to their network. If the interconnect is high, then businesses and consumers end up paying a lot of money for a call. If the interconnect rate is low, business and consumers pay far less. The providers don’t care if the interconnect is high, they prefer it. For them the high cost is offset when these providers pay each other, with businesses and consumers ultimately shouldering the cost and the providers making a lot of money. 

In 2010, as an example, the mobile interconnect rate in South Africa was R1.25. Because of this a technology called Least Cost Routing (LCR) became popular, where a business connected their telephones to sim card devices that allowed calls to mobile networks at substantially reduced rates. Calls to a Vodacom number for example, would route to a Vodacom sim card, resulting in the call always being on-net (Vodacom to Vodacom or MTN to MTN) and not across networks incurring the high interconnect rate. The result was a vastly cheaper per minute rate. However, as the interconnect rate started to drop, so LCR was no longer needed.  

VoIP soon followed where you could use data links like ADSL, Diginet and later Fibre and Wireless to send calls over direct interconnects. This created a gap in the market for smaller providers to enter the market and provide telecom solutions at far better rates than the larger incumbents.

ICASA stepped in in 2012 to regulate this to reduce the burden of call costs on the South African economy, and today the mobile interconnect is set to 9c. Through a combination of the reduction in the interconnect rate, a growing variety of VoIP services and better connectivity solutions, VoIP has now become the favoured method of carrying calls across corporate South Africa.

ICASA differentiates between the big and small providers in terms of the regulated rate to try and give the smaller networks an advantage to help them grow.

Centracom bases its VoIP Rates on a clients call volumes, with call rates starting as low as Interconnect +1c.

The relationship between an ISP and a Fibre Network Provider physically works in a fairly simple way, and most Connectivity business models in South Africa follow the same basic principles. The Fibre Network Provider will have their Last Mile fibre to the building or home of the client and carry the signal on its network or via other providers like DFA (see “How a Fibre Network is built”) all the way back to its server in a large Data Centre. The ISP will be based in the same Data Centre and will connect via a cable to the Network Provider and put their services over the Network Providers network. Most Network Providers in South Africa are based in Teraco in Isando, but there are many other Data Centres around South Africa, and a similar arrangement will be made depending on where the Network Provider aggregates its network.

All ISP’s will be based in the same Data Centre as the Network Provider they wish to connect to and will have a connection from their server to each Network Provider’s server via a physical cable called a “cross-connect”. Because of the growing number of physical cross-connects in a Data Centre modern day Data Centre’s are starting to use “virtual cross-connects” where the network provider is connected to all ISP’s by 1 cable, enabling all ISP’s on the virtual cross-connect to be able to offer their services to all clients on a network providers network. These cross-connects come at a fee charged by the data centre and this is why sometimes you get 1 ISP in a small business or residential complex, and many ISP’s in larger complexes.

A network provider is the company that builds the actual infrastructure in a specific location such as an office park or a housing complex, and an Internet Service Provider (ISP) puts the service across this infrastructure and invoices the client.

The service the ISP delivers is the connection to the Internet and is defined by the speed and capacity of the Internet connection and is responsible for invoicing the client. The ISP then pays the Network Provider a “connection fee” each month. This can cause confusion for a client as e.g. they are told that MFN are in their complex but yet they have to sign up with for the ‘business fibre service’ with Afrihost.

When a Fibre Network Provider allows other ISP’s to supply services across its infrastructure this model is called an Open Access Network. This model is/was most prevalent in the now end-of-life ADSL product from Telkom, and in most Home Fibre services in South Africa. Open Access Connectivity is not common in Microwave or LTE as the infrastructure owners provide the ISP services for LTE and Microwave themselves.

Most Business Fibre Network Providers only offer their own in-house ISP services as they required by the client to offer strict SLA’s. A typical business SLA is a 99.9% uptime of the service, which allows up to 4 hours of downtime per month. Because of this stringent service offering, the Business Fibre Network Providers and can’t afford to have the physical network portion and service portion split between them and an ISP in terms of timings and cost for the client. Also, the management and support of Business Fibre clients falls within business hours and so the networks are happy to do this. Home fibre clients’ require service after business hours so their service desks’ will run 24/7/365, so the Home Fibre ISP make up for the low margins and high support costs with large volumes of clients.

There generally are no SLA’s for Home Fibre services. A repair can take anywhere from a few hours to a few weeks, and they are not contracted to resolve issues quicker. This is called a Best Effort Service. Due to the difficulty in managing thousands of clients 24/7/365, Home Fibre Network Providers offer their infrastructure on an Open Access basis with ISP’s who specialise in marketing to and managing thousands of clients directly and simply paying the network provider the connection fee. A good example of a very big ISP for home users in South Africa is Afrihost.

A new Business Fibre link ordered often requires a Last Mile build from the Metro Layer to the office building. The cost of this Last Mile build is significant and the business fibre Network Provider’s only way of recouping this from a client is to amortise the cost across a fixed term. That is why once you have signed a Business Fibre agreement, it is very difficult to cancel the contract. Only in extreme circumstances will a provider allow the cancellation of an existing fibre agreement.

Factors contributing to long Business Fibre Contract Cost and Terms (12 / 24 / 36 / 60 months)

• Long approval times from Road Authorities
• Significant civil work cost incurred for build
• Only 1 client to recoup cost from
• All costs amortised over long contract Term for client

Home Fibre has a different arrangement in terms of the Last Mile as a single Network Provider will install the fibre within a complex after negotiating with the body corporate and share the cost with all homeowners of the complex when they sign them up.  Installations within a complex are usually run within existing ducting (such as an old gate intercom), lowering the costs further. All that would need to happen when the homeowner makes contact is that that the ISP would install its own router in the home, which will connect to the ONT device left in the home by the Network Provider during the complex installation, or the Network Provider would be called back in by the ISP to connect a new ONT device. A Network Provider can have multiple ISP’s providing service across its network within the complex. These ISP’s sign up the client, provide the service and bill the client each month and pay the Network Provider a monthly “connection fee”.

Factors contributing to short Home Fibre Contract Terms (month-to-month and up)

• Usually 1 Network Provider installs in a complex, the Fibre Provider will eventually recoup its installation cost, and is happy to go in on risk
• An entire complex’s fibre is installed by a Network Provider once and is usually prebuilt before services are marketed within the complex
• Installation costs shared with all owners within a complex and recoupled by Network Provider monthly
• Market competition and client’s requiring freedom to move around leads to month-to-month contracts offered by default

Centracom manages many Business Fibre providers on behalf of its clients and manages new links as well as upgrades and escalates with providers to ensure that any issues affecting a client’s service gets sorted out quickly. In extreme cases of non-performance or the adherence to an SLA, Centracom has sought relief for its clients by facilitating the cancellation of a Business Fibre service.

Fibre Network Providers that have their infrastructure within your business or residential complex have fibre from a meeting point on site (usually near the gate) to your office building or house where they install a Fibre ONT (Optical Network Terminal). This ONT device converts optical light to digital signalling and is installed by the Network Provider for the ISP to connect their router. This router is the device a customer would connect to with WiFi or a network cable. Sometimes where a network provider is also providing the ISP service, they will have the ONT and ISP router within 1 device.

The fibre from the meeting point of your office park or complex to your building or house is called the “Last-Mile Fibre” and most office or residential complexes usually have 1 last mile provider. A second network provider won’t want to incur the expense of “fibering up” an office park or complex unless it is guaranteed all the clients using its network.

The fibre within the office park or residential complex is aggregated at a point usually near the gate and is connected to a Network Providers fibre network that runs down that street. This street is connected to all other streets in that neighbourhood and this collection of interconnected streets in a neighbourhood is called a Metropolitan Area Network (MAN) known as the “Metro Layer”. Each Metro Layer in a city is interconnected by a huge fibre link that runs around a city and is called a “Core Network”. This Core Network connects to the various Data Centres around a city where the ISP’s are hosted. Cities are connected via National Fibre Networks, and these National Fibre Networks are connected to each Undersea Cable system like WACS or EASSY.

What is interesting is that you can have one fibre provider who owns the Last Mile, another fibre provider who owns the Metro Layer, another who owns the Core Network, another who owns the National Fibre Network and then various providers and/or consortiums who own each Undersea Cable connecting South Africa to the world. Because of the cost to build a fibre network, no Network Providers’ network is linear or the same as they are all interconnected in many different ways. In most cases a provider will look to use infrastructure from another provider that already exists provided enough capacity is available at the right price. You get certain providers like DFA who specialise in this space specifically, and whom most fibre networks in South Africa run through.

Building a section of a fibre network takes a lot longer than people think. Apart from the physical build, several approval processes have to be undertaken, as well as the technical setup after the physical build. A fibre network build can be broken in to 4 distinct phases:

Road Agency Approval
In South Africa an approval from each city’s road authority like Joburg Roads Agency (JRA) through the wayleave process is required. This is usually the longest part of the build process due to the volumes of requests on South Africa’s Road Agencies. The wayleave process entitles the holder to bury cables or access utility lines on a road reserve in a specified manner (distance inside reserve and depth of cable to be laid etc.). This is required because a road reserve may have many other services already in the ground such as electricity, water, sewerage etc. and the wayleave process guides a contractor.

Over and above a Roads Authority’s approval, a business or home complex would need approval from the various governing bodies, and this could take additional time.

Civil Work
Once approvals from the Roads Authority have been received, a civil contractor will need to start with the digging of the trench to lay the fibre withing. Once dug, a conduit pipe gets put down as well as the fibre ducting within the conduit. This is handled by the sub-contractor. This can take long as some builds require the trench to go under roads, rivers, rock, water pipes, sewerage and other obstacles.

Fibre Infrastructure
Once the trench has been backfilled and checked, only then is the fibre “blown” into the duct via an air compressor. Once the fibre cable is in, it is then spliced (joined via heat fusion) and connected to the passive equipment of the network provider on both ends.

Link Setup
Once the fibre is “lit” (active equipment installed) and working then the setup on the technical provisioning side is commenced. This takes in to account any ISP settings as well as any client settings required. Once this is complete it is then handed over to Centracom and the client can commence using the fibre.
Centracom manages all installations with each provider on behalf of its clients via its Project Management Office. Centracom manages the entire process, reducing installation times for its clients.

Business Fibre requires a large amount of civil work to get new fibre trenched and ducted to a new client. This all depends on the distance and any other obstacles like roads and bridges and rivers etc.. The cost is usually significant as the civil contractors are paid upfront for the work, and the Network Provider will amortize these costs across a fixed term with the client.

Home fibre installations are cheaper because this installation cost is shared by all homeowners within a complex. The fibre providers installs on risk as they don’t directly recoup the costs with each homeowner, but are happy to recoup these costs when each homeowner signs up across time as they are usually the only provider in the complex.

Sometimes a business gets lucky with a business fibre provider approaching a business complex in a similar fashion as Home Fibre complexes. The Network Operator is happy to offer better Terms and a more competitive cost for the Business Fibre Solution, and in some instances may appoint a Business ISP to manage the complex. This arrangement is on a business complex by complex basis.

Centracom uses Pindrop, a sister company of Centracom to manage all of it’s Connectivity. Pindrop has mapped and/or integrated via API with over 50 providers on its platform. A location is searched on Pindrop via a Google Maps lookup, and all providers are interrogated live for line-of-site, and subsequent pricing at that location. Centracom via Pindrop has a commercial arrangement with each provider in South Africa.

Most Network Providers and or ISP have a service like this running for themselves, but nobody in South Africa offers this service for all Networks of Business Connectivity Services and manages each service installation, support, and billing directly like Pindrop and Centracom.

An example of this tool, albeit a watered-down version, is available on this website found here.

Business fibre and wireless connectivity are two different types of technologies that businesses can use to connect to the internet and other networks.

Business fibre refers to a type of internet connectivity that uses fibre-optic cables to transmit data. These cables are made of thin strands of glass or plastic that transmit data as pulses of light. Business fibre is generally considered to be one of the most reliable and high-speed options available, capable of delivering symmetrical upload and download speeds with low latency. It is typically more expensive than other types of connectivity, but can provide greater reliability and bandwidth for businesses that require fast and consistent internet connectivity.

Wireless connectivity, on the other hand, uses radio waves to transmit data through the air between devices. This includes technologies such as Wi-Fi and cellular data networks. Wireless connectivity is generally more convenient and flexible than fibre, as it doesn’t require physical cables to be laid and can be accessed from a wider range of devices. However, wireless networks can be more susceptible to interference and signal degradation, which can result in slower speeds and less reliable connectivity.

Overall, the choice between business fibre and wireless connectivity will depend on a business’s specific needs and budget. Businesses that require fast, reliable, and consistent internet connectivity may prefer fibre, while those that need more flexibility, convenience at an affordable price may opt for wireless connectivity.