SIP Trunking — an attractive alternative to ISDN30s
If your company uses ISDN30s, you could probably save a tidy sum by switching to SIP Trunking.
SIP Trunking uses a high-quality data connection to connect your company's PBX to the public telephone network. This eliminates the need to rent comparatively expensive ISDN30 circuits.
With SIP Trunking, your phone calls, internet access and WAN connectivity can all make use of the same data connection. This offers numerous benefits:
SIP Trunking can save you money
You can reduce or eliminate your spending on ISDN30 lines. You'll get cheaper call rates, and you'll no longer have to buy ISDN line cards for your PBX.
SIP Trunking lets you add channels incrementally
Need to add a single phone line? No problem. Need to add 100? No problem. Unlike ISDN30 circuits, you don't need to add 8 to 30 channels at a time. As long as you have 80kbps of bandwidth spare, you can add another SIP Trunk.
SIP Trunking increases peak capacity by pooling your voice and data connections
If lots of people are on the phone at the same time, your phone service can borrow bandwidth from your internet connection.
If few people are on the phone, your internet connection can borrow the bandwidth that's not being used for making phone calls.
SIP Trunking can make your phone system more resilient
Most companies have a single point of failure: their ISDN30 circuit. If that circuit goes down, they have no phone service.
The same is true with SIP Trunking, if you just use one data circuit to connect to the phone network, you'll lose your phone service if that circuit goes down.
Luckily, the substantial cost saving that come from switching to SIP can subsidise the cost of getting a backup connection that improves your network's resilience.
If your primary data circuit were to go down, your calls could be re-routed over a backup data connection, or even over an ISDN circuit.
SIP Trunking will work with your existing PBX
Most modern IP-PBXs come with built-in SIP Trunking.
Even if you don’t have a modern PBX, you can still use SIP Trunking. You will just need a SIP-ISDN gateway to translate the SIP Trunk signals into something your PBX can understand.
SIP Trunking offers a phased migration path
If you like the sound of SIP, but are wary of switching from trusted ISDN, there's a phased approach that might appeal to you. It allows you to get some of the cost savings of SIP, while being able to switch back to ISDN at a moment's notice.
Here's how it works. Incoming calls continue to come in via ISDN. Outgoing calls are intercepted by a SIP-ISDN gateway, and travel out via SIP. Your existing ISDN circuit stays in place, and provides backup connectivity to your SIP trunks.
SIP Trunking call quality requires a good network, set up correctly
Phone calls are temperamental things. They are very sensitive to delay (latency), variations in delay (jitter), and information getting lost (packet loss).
To ensure good call quality you need to ensure that
- phone calls are given priority over less time-sensitive traffic (web/email/WAN etc)
- there should be no network congestion between your PBX and your SIP Trunk telephony provider.
SIP Trunking: It's ready right now
Following extensive testing in our lab, our voice engineers decided to switch the trunking on hSo's own internal office phone system from ISDN to SIP. Nobody here noticed any difference in call quality. If SIP Trunking is set up correctly, you won't notice a difference either, except to your phone bill.
It's just a matter of time until SIP Trunking becomes the standard way of connecting corporate PBXs to the telephone network.
Find out more about SIP Trunking
For more information on SIP Trunking, please visit www.hso.co.uk/sip-trunking .
Or give your hSo account manager a call on 08700 638 739.