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SIP Trunks for Call Centres

A Hostcomm SIP trunk will quickly connect your contact centre’s PBX to the public switched telephone network (PSTN) providing a more cost effective alternative to ISDN for both inbound and outbound voice telephone calls.

As more call centres make the move to VoIP, many are choosing Hostcomm for their SIP trunk and hosted VoIP services. That’s because we manage and operate our own business VoIP network.

SIP Trunks deliver great business benefits:

  • Cut communications costs. A Hostcomm VoIP line costs as little as one sixth of the rental of an ISDN line. Call costs, especially long-distance, are greatly reduced with our highly competitive rates.
  • Increased flexibility. ISDN lines are fixed and can take weeks to move. Our service reaches any geographic location with broadband. If you move, our channels can move with you in minutes. And if you need more lines, we can provide you with what you require straight away.
  • Security against fraud. We use the latest security measures to guarantee fraud protection. Firewalls, intuitive detection and continuous monitoring, protect your business from fraud and other security infringements.
  • Increased reliability. Unlike many VoIP providers, Hostcomm uses up to five major UK telephone carriers. If one suffers an outage or network problem, your service continues on another, protecting your business from costly interruptions.
  • Streamlined call centre processes. The Hostcomm network is configured to work with dialler traffic – calls that are high volume, simultaneous and short in duration. We offer a reliable, secure service to meet specific call centre needs which can boost performance and improve customer service.
  • High quality business grade VoIP. Hostcomm complies with all Ofcom regulations and uses the highest quality routes by peering directly to UK tier 1 carriers, using our own network.
  • Easier management. Reduce operational and maintenance headaches. Using our web portal, you can manage your service 24-hours a day.
  • Unified Communications supported. Our network supports SIP over TCP, used by Microsoft Lync software for carrying instant messages, video conferences, presence and other real-time communications.
  • Instant Hassle-free set up. Our automated provisioning system offers your business fast, automated set up via our website. Or, you can speak to one of our experts to guide you through the process. We have experience with Asterisk, Cisco, Vicidial, Avaya, Splicecom 3CX and many others.

Why choose Hostcomm?

Hostcomm hosted VoIP is a flexible service provided as a monthly subscription. There's no need to invest in expensive ISDN lines or on-premise hardware. Gain access to your service immediately, with our automatic provisioning service, operating 24 hours a day. We also offer unlimited technical support during UK business hours. Choosing the best service provider is critical to service quality and your brand.

Hostcomm has over 10 years’ experience in call centre services. As SIP trunking providers, we can meet the specific needs of any size business, from smaller companies to large enterprises, and even offer special services designed for call centres and heavy outbound dialling. Whatever your need, Hostcomm can help.

Hundreds of organisations such as Towergate Insurance, NPS, Bertelsmann Group and Budget Car Rental have already switched to Hostcomm for VoIP services.

Choosing the best VoIP service provider for SIP trunking is critical to service quality and your brand.

What is a SIP trunk?

A SIP trunk is the VoIP alternative to traditional ISDN services. It is an interface for your communications network, connecting your voice calls over an IP network, eliminating the need for physical ISDN lines. This can cut your telephony costs and bring you increased flexibility as your lines are not fixed – they can move with you. The Hostcomm SIP trunk service can expand easily to meet your needs, unlike fixed ISDN lines. It can also offer great service availability, utilising multiple carrier routes.

SIP Trunks for Predictive Diallers

Hostcomm's SIP trunk service can provide you with hundreds of lines; load balanced across multiple carriers to ensure calling continuity in the event of a carrier problem. It can also handle high calls per second (CPS) rates, low average call duration (ACD) and connect rates (ASR).

Hostcomm's business VoIP service is ideal for large organisations for the following reasons:

Quality of the service

VoIP services are generally classified into Platinum, Gold and Silver categories with the quality of service reducing respectively. A silver service can look commercially appealing but the calls may be routed internationally before reaching your UK phone. Sometimes silver services do not consistently present caller line ID (CLID), this is a breach of Ofcom regulations for call centres. The call quality can be patchy and have latency (delay) between the called and caller. Hostcomm always provides a high quality voip service unless requested specifically to lower the quality in favour of price.


Hostcomm peers with multiple carriers and can continue terminating calls seamlessly or with little downtime, in the event that carrier route fails. A softswitch is required to do this, Hostcomm has two of them in separate data centres. Softswitches aggregate carrier routes and can load balance between them. This is necessary for resilience but also to manage the calls per second rate. Pushing traffic through carriers with high rates of calls per second can lead to you being suspended. Carriers do not like high volume short duration traffic because it can make their gateways freeze which would affect lots of their clients.

Designed for Business

VoIP service providers measure their performance based on two main targets; Average Call Duration (ACD) and Answer-Seizure Ratio (ASR). Call centre VoIP traffic generally delivers low call duration and low answer rate, this is not popular with most carriers. Hostcomm has designed its network and uses its load balancing capabilities to ensure that all carriers receive satisfactory ACD and ASR rates.

Location of gateways

If you are calling in the UK the voip service provider should have gateways or softswitches located in the UK at multiple locations. This is necessary to ensure that latency is kept to a minimum and also to ensure that CLI is presented correctly to the called party. If the gateways are not in the UK the caller ID may present to the called party in full international format which can be confusing.

Secure connectivity

The service provider should be able to furnish you with a security policy stating how they secure their service. Telecoms fraud is very common and can lead to a significant losses if you dont get the right advice. Hostcomm has many security measures in place to lock out unauthorised use of your business VoIP service such as IP address authentication, custom A-Z tariff sheets, time of day call blocking. We also have the in-house expertise to help you secure your PBX.

PBX experience

Hostcomm has years of experience with Cisco and Asterisk PBXs and it can provide you with assistance in the setting up of a trunk with all major service providers including Avaya, FreeSwitch, Vicidial, 3CX and Microsoft Lync.