All about VoIP

The rise of SIP Trunking

As one of the most important aspects of a company’s infrastructure, it is imperative that its communications systems can support employees in their day-to-day activities in communicating with each other and with customers across offices and across countries. Traditionally, voice networks have run separately to IP networks, but as companies look to streamline technologies and make their business more flexible and efficient, a greater demand for moving to a single converged IP infrastructure is inevitable.

Many organisations have implemented or are about to implement SIP trunking services. As a result of that we have just seen the United Kingdom SIP trunking market passing the mark of one million trunks. Moving from a traditional voice line services to nowadays matured IP telephony is resulting in a migration need for the equipment – from a TDM telephony to a SIP-based private branch exchange (PBX).

Previous barriers to adoption have been the investment into new equipment, migration cost and the maturity of technology vendors that support SIP trunking. Whilst SIP is a standardised IETF protocol stack, the standards have been implemented by equipment vendors slightly differently. Therefore service providers have had to adapt to vendor requirements by ensuring that their infrastructure can support them.

Colt have carried out and proven interoperability with major vendors such as Cisco, Avaya, and Microsoft Lync to simplify the implementation for our corporate customers, but as well to satisfy the interoperability needs of our Operator and Wholesale customers. For non-certified PBX’s we offer dedicated engineering support, helping our customers across Europe to get any IP PBX up and running.

The barrier to migration is now being eroded by organisations need to reduce operating costs for the network and their business’ need to improve flexibility and mobility to their workforce to enhance productivity. SIP trunking as an investment is paying back especially when voice and data networks are converged onto one common backbone.

The Colt offering

Colt’s VoIP Access removes the need for separate voice and IP networks. Customers can easily utilise a single converged infrastructure for voice and data across their multiple sites.

The VoIP Access service is a fully-featured SIP-based voice telephony service, which connects the customer’s IP-PBX (private branch exchange) in the most efficient way to the public telephony. The variety of connectivity options ranges from a shared internet access to dedicated connectivity via Colt’s Ethernet Private Network or an IP-VPN.

Colt’s VoIP Access features enable customers to more easily secure their VoIP traffic, retrieve online in-depth analysis of traffic, performance, network utilisation and generate call monitoring reports. Customers benefit from a highly available and reliable VoIP service due to resiliency options enabling multiple trunks and customer site redundancy, and disaster recovery capabilities such as call diversion to an IP address.

VoIP Acces is available either for corporate customers and for Operators, that can resale the solution to their end customers, optionally also with our White-Label bundle of additional services.

Colt’s Number Hosting offering mainly addresses Operators running their own VoIP platforms who want to flexible build and sell their own propositions under their own brand. It enables the expansion of the Operator’s service offering into new geographies without having to invest in national interconnects and local processes.

Colt manages multi-country inbound and outbound traffic via a single IP connectivity. Customers can process their high-volume transcations on number management including reservation, activation and porting of numbers in a fully-automated way via Colt’s market-leading B2B interface Cocom while they keep full control of their business through daily unrated CDRs and comprehensive reporting capabilities. Colt takes care about the regulatory compliance, emergency call routing and lawful intercept.

Colt’s IP Voice Line service follows the traditional TDM-based Voice Line service, combining the benefits of an IP-based voice backbone and a converged access to the customer’s site with the continuous operating of a traditional TDM PBX (private branch exchange).

IP Voice Line can be operated as a standalone voice solution on any shared IP access service. Alternatively the VoIP service can be bundled with a Colt provided IP Access service. Smaller customers’ needs can be addressed via BRI ports, uncompressed high quality voice is available even when the access is DSL-based.

Market reflection

The relevance and maturity of SIP trunking in nowadays telecommunication business is proven by the fact that it is listed in Gartner’s latest “Critical Capabilities Report for Pan-European Network Services”. As a recognition of Colt’s continued investment our rating for SIP trunks have improved to 4.5. This is as well reflecting Colt’s capability to provide a consistent SIP trunking service across 13 Western European countries based on a future proof platform and a competitive feature set and pricing.

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