Interview

The Value in SIP

Who needs ISDN? Well, it seems a whole bunch of people still rely on ISDN as their main form of voice connectivity but increasingly users are turning to SIP. Why is that? What are the advantages? In fact, what are the pros and cons? We talk to Adrian Hughes of AVC

As more and more UK businesses outgrow their telecommunications solutions, they begin to look for an alternative that offers more flexibility, reliability and value for money. Does SIP outperform ISDN in all three areas?

Comms Business Magazine (CBM): Are users sufficiently confident in SIP to ditch their ISDN lines? 

Adrian Hughes (AH): Most Service Providers still advise clients to use SIP with an ISDN backup or vice versa. This is because the reliability and security issues on internet-based SIP services cannot be resolved as we lose visibility and control. The internet is simply not designed to carry telephone calls. The correct way to deliver SIP services is via a guaranteed, secure private IP network (Private Cloud) with an engineered SLA. This offers the same quality, security and reliability as ISDN but approximately 40/50% under the current BT base price. The truth is that the further away from this model resellers move, the further away from ISDN reliability they travel.

CBM: Are there real cost savings to be made? 

AH: Yes, but resellers should be aware of the difference between value for money, and cheap. Value for money is a SIP service which is typically 40% cheaper than ISDN channel for channel, but offers the same or better SLA in terms of quality, security and reliability. SIP trunks delivered over the internet may be even cheaper, but typically deliver a ‘Skype-style’ user experience. Now that may be acceptable for the SOHO market but it is not realistic for a serious SME.

CBM: Do the business continuity features of SIP trunks stack up?

AH:  In a business continuity scenario, for example, no access to a Head Office due to an environmental or loss of service issue, at AVC with SIP trunks we can forward program a backup dial plan to automatically activate if we cease to see the site via our ‘heartbeat’ feature between the end points and our platform. Alternatively call diversion is available on both ISDN and SIP services via our admin Portals.  The advantages of business continuity really come into their own in a hosted services scenario, where a cloud based telephony service accessed via SIP can deliver calls to any device under any conditions.

CBM: Do you think that SIP truck security is adequately addressed? 

AH: I think that there is a security risk with telephone calls being delivered over an insecure, public infrastructure like the internet. This is a further reason why partners serious about selling Hosted telephony should make sure they choose a service provider than can offer private cloud based telephony on a secure, robust layer 2/3 network with endpoints managed and monitored end to end.  Deploying hosted Telephony through a secure, encrypted tunnel will reduce the risk of fraud but even this does not guarantee quality of service or reliability. The most secure service will be the one delivered via a guaranteed, secure private IP network with an engineered SLA.

CBM: What about overlay services? 

AH: Overlay services such as hosted PABX, unified communications, call recording and even hosted call centres are a reality today. By using Broadsoft SIP Trunks we can overlay these different classes of service on to an existing asset based PBX down to a granularity such as additional voicemail boxes, mixing hosted extensions with the PBX and even extension dialing between the two types of deployments is possible.

CBM: What can AVC One offer resellers in this market?

AH: Creative support in selling and securing business for resellers, a unique licensing model and flexible billing application that can be white labelled.

In simple terms we can offer basic SIP trunks for telephony as well as a fully featured service for all the value add overlay services that help resellers retain customers and build revenues.

There are some suppliers that offer SIP trunks for free but beware, these are only suitable for telephony at best – there is no intelligence built in. Whereas if your client wants cloud based call queues, disaster recovery, a centralised operator, cloud auto attendant and UC you will need to go for a fully featured service such as our own.