Lines and Calls

Since 2005, BT Openreach (a division of the BT Group) has made it possible for independent telecoms companies to offer discounted BT line rental and discounted telephone call traffic as part of their portfolio. Backed by Ofcom, the product you get through Cityvoice is exactly the same as that you would buy direct.


Aside from achieving considerable savings. The discounted BT line rental and telephone call traffic is managed by our London based team, not a faceless call centre: end to end responsibility sits with us. Let us talk telecoms jargon to BT, it’s all part of the service.

Businesses that are relocating or refurbishing their offices will benefit from local lines and calls management. Our office movers consultancy access use the BT tools to help manage new installations and line moves – all part of the strategic project management.

The Cityvoice teams have access to BT’s BT line rental, provisioning and maintenance systems, allowing orders from the full portfolio of BT products through Cityvoice.

SIP Trunking Service (aka SIP ISDN / VoIP Lines)

Cityvoice provide the ability to run lines to telephony systems, via an Internet connection. The advantage of a SIP trunking service is to provide an alternative to BT lines rentals, offering resilience and disaster recovery options.

Within the core of a telephone carrier’s network (BT, Colt, Cable & Wireless etc) voice travels in Internet Protocol (IP) format and has done for some time. It is the local Telephone Exchange at either end that turns this signaling in to ISDN, the line format traditional telephone systems use to make calls.

Many latest generation of telephone systems are sophisticated enough to accept ‘IP’ traffic directly, bypassing the Telephone Exchange. Why would you do this?

SIP ISDN has cheaper monthly rental, mainly because your Internet service is used to pass calls over rather than lines provided by the local BT Exchange.

SIP ISDN can provide telephone line resiliency. It is commonplace for Telephone systems to have a mixture of traditional ISDN and SIP ISDN – if one fails the other takes over. An ideal disaster recovery option.

SIP ISDN allows ported numbers to terminate directly in to a telephone system.

Cityvoice communication consultancy team specialise in delivery a mix of traditional BT line rentals with SIP trunking services

Business Call Packages

Through our carrier partners we offer bespoke business call packages with the aim of saving your business money.

It is good practice to review business calls rates every 12-24 months as rates change reasonably regularly, usually getting cheaper. Our teams will be able to analyse your current expenditure and calculate projected savings too. It’s a free service and we’d be happy to help.

Similarly, if your business uses Non-Geographic Numbers (0800, 0845, 0870 etc) or is looking to implement such a facility, speak to our team who will be able to consult on and competitively price your requirements.

Next Generation Networks

Historically telephone numbers were strictly bound to Telephone Exchange areas. Moving office often meant giving up telephone numbers that customers were used to – a significant disadvantage in some business sectors. Our office movers consultancy can advise on how this works.

Ofcom, the UK regulatory body for Telecommunications in the UK, has approved a Number Porting process to allow numbers to be transferred to ‘next generation networks’ (NGN), effectively a countrywide Telephone Exchange held within secure Data Centres. The NGN is then setup to forward calls to your site(s), either using SIP ISDN or a simple phone call.

Enhancing this is our ‘Inbound’ offering. This adds rules to the routing of your calls to allow you to; manage a multi-site call centre, provide a ready-made disaster recovery option or simply provide some call statistics. All without expensive hardware – Inbound will revolutionise the way calls are handled.


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