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Understanding Business VoIP Providers and CSIs

|  4 min
VoIP Providers and CSIs
In this article

In getting to grips with the various types of VoIP providers and networks, it is important to know and understand what underpins each network in terms of infrastructure. The Carrier Services Infrastructure (CSI) is essentially a highway system through which all communications (both public and private) travel. Whichever network type you opt for in running your VoIP solution, it will always be a subnetwork of a much larger CSI. 

CSIs can be characterised in numerous ways. They may have a large bandwidth capacity or a limited bandwidth capacity. They might be single-channel or multichannel, switched or dedicated, circuit-switched or indeed packet-switched. 

Five CSIs currently exist. They are: Wireless, PSTN switched, OS dedicated, DS dedicated and HFC dedicated. 

The Public Switched Telephone Network (PSTN) dates back to the 1870s. As its name suggests, it is a switched network. In terms of VoIP transports, it uses PRI line or DSL using a POTS line. Its VoIP service options include VoIP over PRI (primary rate interface) and VoIP over broadband DSL (VoDSL). 

The digital service (DS) network was incorporated in 1964 and is a dedicated network. In terms of VoIP transports, it uses DS1 (T1) or DS3 (T3) and its VoIP service option is VoIP over PDN (private dedicated network) channels. 

Optical Carriers (OC) saw inception in the 1980s. Like DS, they are a dedicated network. They use OC3 or OC12 VoIP transports and in terms of VoIP service options, they offer VoIP over PDN channels. The OC networks are sometimes also used in the provisioning of other dedicated transports such as DS3 or DS1. 

The 1980s also saw the introduction of Hybrid fibre-cable networks (HFCs). Again, this is a dedicated network and one that uses Cable fibre for its VoIP transport. It offers VoIP over broadband cable modems. 

The early 2000s saw the introduction of Wireless CSI. Wireless is a switched as opposed to a dedicated network. In terms of VoIP transports, it uses frequency spectrum channels. The VoIP service options on offer here include VoIP soft phone for pocket PC, VoIP over Wi-Fi (VoWiFi), and VoIP over WiMax (VoWiMax). With the wireless CSI, whilst it may ultimately use lines at its core, there are no lines in the physical sense for the customer. Instead, there are dedicated frequency spectrums and frequency channels. 

CSIs themselves are not owned by any single carrier – all carriers own a portion of each one. They each lease what they do own to/from other carriers at wholesale rates and then resell to their customers. Most carriers are able to lease network transports from all five of the CSIs. Each CSI contains different types of network lines/services. 

Dedicated, packet-switched networks are the optimum solution for VoIP. For businesses with multiple disparate locations, this would mean the principal use of transports from the DS and OC CSIs. In addition, wireless transports are routinely used in addressing the requirements of remote services. 

VoIP providers /carriers

Carrier firms are constantly upgrading their network equipment and transport lines across every one of the five CSIs. They are also able to grow through mergers/takeovers – to gain broader CSI coverage. Broad and comprehensive CSI coverage is important when running VoIP across a multi-location network. Businesses need to ensure that their lines can be dedicated to their VoIP network 24/7/365. It is not really relevant who owns what part of which CSI. Having said that, if you are able to utilise dedicated lines that are solely owned by a single company, it may make maintenance easier than with a line that is owned by several firms. 

Picking a provider

VoIP telephony solutions offer fantastic cost savings, improved productivity, great call quality, and useful extra features. In looking to choose a VoIP provider, there are a number of things that you should take into consideration. Value, service quality and reliability are probably the most important elements. Whilst price is important, it should never be the only priority. Instead, it should be value for money that is the driving factor. 

If a medium cost option is superior in terms of quality and reliability compared to the lowest cost offering then from a value perspective that would be the most sensible choice. Due to the ultra-competitive marketplace, in theory at least, the price differential between providers should not be that significant, allowing clients to focus on quality, reliability and scalability. 

Business VoIP providers

Here at IDT, we provide a wide range of VoIP services, including but not limited to wholesale and retail call termination. We have been at the forefront of the industry for over 25 years and have coverage in almost 50 countries across the globe. If you are looking for a reputable firm to provide your business with VoIP solutions, why not explore our website or contact our expert team to see how we can help? 

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