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What is Sip Trunking or Sip Trunk

Beginner’s guide to SIP-Trunking!

Among telecommunications experts SIP-Trunking is a popular buzzword. Do you also want to have a say? Sipwise has all the juicy facts you need!

Quick history check on SIP- Trunking

To understand the potential and prowess of SIP-Trunking – we’ll conduct a small excursion to the beginnings of telecommunication. Since the dawn of telephony in the 19th century, the infrastructure to make telephone calls possible has been physical copper lines – every end device needed a corresponding line to connect with the PSTN. This method has existed since the introduction of the plain old telephony system – so for far more than 100 years! ISDN was launched in 1988, enabling cheaper, more flexible and better quality communication. Still, back then, companies and carriers were still a long way from experiencing and providing communications services that we are expecting today. Due the diffusion of the Internet, cloud technology and fibre optic wiring we now enjoy faster and more stable connections than ever, using the data network (i.e. the Internet) to transmit all kinds of data – with low downtime and latency.
 Welcome to the fascinating world of VoIP-telephony and Unified Communications!

What is SIP-Trunking (or a SIP-Trunk)?

SIP-Trunks are used in VoIP-telephony and serve to connect telephone systems to the Internet or to cloud services, if necessary. A SIP-Trunk is the virtual counterpart of an analog phone line. Using SIP technology, voice and data can be sent back and forth between communication parties over the Internet. SIP-Trunking is fundamentally different from other telephony systems as it’s built on IP-technology and relies on data networks instead of copper lines to transmit voice calls. Moreover, you can use the same network for transmitting a variety of data – from voice, text, documents to video conferences. Hence, if there’s a problem, there’s only one network to troubleshoot!

How does SIP-Trunking work?

Have you had experience with ISDN-telephony systems? Than you are probably familiar with a PRI connection, used to connect business PBX to ISDN. Basically, the SIP-Trunk is the equivalent to the classic PRI connection.
VoIP-providers can use SIP-Trunks to link voice channels to their customers’ PBX. A single „Trunk“ enables direct dialing to multiple devices with their respective extensions. Depending on the bandwith of your IP-connection and configuration of PBX, the number of voice channels assigned to the SIP-Trunk can vary greatly. So the technical capacity provided, you could employ a million voice channels per SIP-Trunk, if that’s how many calls your business expects to receive and conduct.
Since the SIP-Trunk registers entire telephone number blocks of your PBX (including extensions) on the SIP-provider’s server – not just individual phone numbers – all end devices can be dialed via a single account!

How can companies and entreprises benefit from SIP-Trunking?

When you operate your business telephony system via ISDN lines, the next paragraph will be thrilling to you. VoIP- and SIP-Trunking allow for so many crystal-clear advantages, it’s astounding.

  • Scalability & Flexibility! You can increase your voice channels anytime, no extra hardware or extensive installations required. In fact you only need one SIP-account to access and connect all your end devices!
  • Cost-savings! Internal calls are transmitted via data network, there is no need to connect to the PSTN anymore. That holds true even for holding calls to branches abroad! Charges for external and long-distance calls are also much lower than ISDN lines. Expect to see your telephone bills shrink to 50% of their original size!
  • Number portability! – You can easily keep your existing phone numbers – because SIP-Trunks are not tied to a specific location. Number porting is also possible when changing providers -your clients will be pleased!

So are you launching a new branch – maybe in a different location abroad? In regards of company PBX and telephony: employ VoIP-/ SIP-Trunking services and go for it.

What do companies need to get started?

How do Telcos and carriers benefit from SIP-Trunking?

Are you providing communications services and invested substantial time, money and manpower in building and distributing physical network technology? Are you hesitant to make the switch to IP? Let’s break down the advantages!

  • Enhance customer value! Operators can use SIP-Trunks to easily enhance their product portfolio with hosted Unified Communications and collaboration services! SIP-Trunks have the ability to transfer packets of multimedia data – e.g. text, audio or video. So delight your customers with a fully integrated package.
  • Reduce cost and increase flexibility! SIP-Trunks are way cheaper to maintain and more flexible during demand peaks.
  • Scale up your business! You can enter markets in regions where you do not own or control any telecommunications infrastructure since SIP-Trunking relies on broadband – not on PSTN connections.

Are you interested in IP-based communications platforms to replace legacy systems and provide over-the-top (OTT) services for your customers? Sipwise provides core switching infrastructure for telecom operators. Contact the team – we are excited to guide you.

SIP-Trunking in a nutshell

  • A SIP-Trunk is the virtual counterpart of an analog / copper phone line in VoIP-telephony.
  • Data networks (i.e. the Internet) are used to transmit voice and media.
  • Scalable, flexible and extremely cost-effective in comparison to legacy technology (Analog/ISDN).
  • SIP-Trunking enables telcos and carriers to deliver unified communications and collaboration services to their clients.
  • Requirements: compatible hardware, VoIP-media gateway for companies, Next-Gen Communications Platform for service operators.

About Sipwise

Sipwise’s unified communication platforms are targeted at fixed, converged and wireless service providers supporting a variety of access technologies like mobile radio, Cable, xDSL, FTTx, WiFi and WiMAX. With years of expertise in VoIP and UC solutions, Sipwise works with clients all over the world and is supporting over 100 deployments by MNOs, MVNOs, Telcos, cable network providers, utilities and “Over-the-Top”- operators.
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