What is SIP trunking and how does it work?
SIP Trunking is the simplest and most cost-effective way to connect your existing PBX or Unified Communications system to the public switched telephony network (PSTN). It leverages your WAN or data network to deliver calls to and from the PSTN, alleviating the need to pay for expensive ISDN services.
Frequently asked questions
- Why should I move to a SIP Trunk?
Customers who leverage SIP Trunks gain benefits such as:
- Cost savings (over traditional ISDN)
- More flexibility and control over call routing (web-based configuration options)
- Business continuity and disaster recovery (e.g. call forward network unreachable and enterprise trunking options)
- How many channels do I need for my business?
As a rule of thumb we recommend you get one SIP channel for every 5 handset users in your business. However, every business is slightly different, so we will help you analyse your bill and usage and determine the channels that are right for you.
- How much bandwidth do I need for my SIP Trunk?
We use the G.711 audio codec for each call. For 10 channels of SIP trunking you will require a 1Mbps symmetrical network link from Brennan IT.
- Will Brennan IT SIP Trunking work with my PBX?
Your phone system needs to be SIP or IP ready (an IP-PBX). Traditional or Non SIP ready phone systems can also be made to work with SIP Trunks via a voice gateway or IAD (Integrated Access Device), we can optionally provide this for you.
- What PBX equipment vendors will work with Brennan IT SIP Trunking?
We have a comprehensive list of compatible PBX systems and known working configurations for these. Let us know your PBX name and model and we will confirm if supported.
- What technology platform delivers Brennan IT SIP Trunking?
Brennan IT SIP Trunks are delivered using the state of the art fully redundant BroadSoft BroadWorks® platform. BroadSoft’s platform is used by the majority of large voice carriers around the world and supports multiple standards including SIPconnect 1.1. SIP Forum’s SIPconnect is an industry-wide standard that provides direct IP peering between SIP-enabled IP PBXs and VoIP service provider networks.
- Why do I need a dedicated link for SIP trunk?
Unlike other providers who use Over the Top (OTT) internet delivery of SIP, we only deliver SIP over dedicated data links. This means we guarantee your voice quality and that you will be able to use the full channel capacity we provide you. Over the internet providers cannot guarantee audio quality or channel capacity.
- Can I bring my numbers/DIDs with me to Brennan IT?
Yes, of course! As a leading SIP provider in Australia, we will organise a number port from your carrier to us and we will manage your numbers for you.
- Can I bring my inbound 1300 and 1800 numbers with me to Brennan IT on my SIP trunk?
Yes, of course! We will organise a number port from your carrier to us and we will manage your numbers for you.
- Do I have to purchase my SIP trunk in multiples of 10 like I did my ISDN service?
No, we are really flexible. We will let you specify exactly how many channels you need for your business. We also let you scale up your service as your business grows simply and easily.
- Will my fax service connected off my PBX still work?
Yes, our SIP trunks support T.38 or fax passthrough. If there are any challenges we can provide you other options for your fax service such as Fax to Email or a dedicated analogue PSTN service.