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SIP posts

  • By Andrew Jordan
    Bring Your Own Numbers with Twilio SIP Interfaces Twilio Bug Logo

    Using Twilio’s SIP Interfaces, you can take advantage of Twilio’s Voice API with numbers on another carrier. Let’s say you have a great relationship and a ton of numbers with your local provider, or you need new numbers in a country we don’t cover (yet). If you need a conferencing service, IVR or the ability to route calls to WebRTC you can add those capabilities to your existing numbers with SIP Interfaces.

    In this post we’ll walk through how to get set up with a number from an external number provider. For this walkthrough we’ll use Toll Free Forwarding but there are many similar providers. Any provider who can deliver calls over SIP will work, and the process to connect them will be similar to the one described here.

    To get this setup we need to configure the Twilio side and then the carrier side.

    In order to send traffic …

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  • By Kyle Kelly-Yahner
    Connecting Cisco Gateways To Twilio Elastic SIP Trunking cloverhoundheader

    There’s a common phrase you’ll hear from big telecom vendors when you’re trying to get phone connectivity in your office: “your estimate is 90 days.” In the middle of that waiting period, if you change any aspect of the planned PBX installation, you’ll hear the same phrase “your estimate is 90 days.” The days spent waiting add up to missed calls, and unnecessary expenses for small businesses. Getting calls into your office can seem unnecessarily hard. Chad Stachowicz, CEO of Cloverhound, gets his clients up and running making and receiving calls fast. A key tool in his toolbelt is Twilio’s Elastic SIP Trunking.

    “There’s thousands of us [telecom developers] running around out there, and we all have our little labs. One of the most annoying things is getting calls into your lab.” Chad founded his own full service communication company (lab, in Chad’s words) to help businesses with …

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  • By Al Cook
    Introducing the General Availability of Twilio Elastic SIP Trunking Twilio_Blog_SIP-Trunking

    Today we are happy to announce the general availability of Twilio Elastic SIP Trunking. Today’s launch brings instant provisioning, contract-free transparent pricing and global availability to the world of SIP Trunking. The SIP industry modeled itself on the technology (and buying experiences) of the by-gone 1870s. Elastic SIP Trunking brings ease of use, internet scale, and a modern approach to using SIP.

    We know SIP Trunking can seem pretty boring. PSTN connectivity for PBXs and Call Centers is mission critical stuff, but not everyone’s cup of tea. But there’s something that really intrigued us about SIP Trunking.

    Even though SIP Trunking has been an option for providing dial-tone to IP infrastructure for nearly two decades, 80% of the world’s enterprises still use the technology that came before it – connecting voice over dedicated time-division multiplexed (TDM) lines. TDM, in case you weren’t paying attention in history class, encodes media …

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  • By Ari Sigal
    Add WebRTC To Your PBX or Call Center In 5 minutes Twilio_Blog_SIP-Trunking

     Your employees are working remotely, from home, airports, hotels, customer locations and coffee shops. Wherever they are, they’re not in the office as much anymore. You’ve introduced tools to allow them to communicate efficiently across teams, no matter where they are.  But, finding the right tool for voice communications is still problematic.

    Twilio can help you solve this problem with our SIP to WebRTC solution and a sample application to help you get started.

    Today many PBX’s and call center’s have a softphone feature and you could deploy these software clients. But these clients are yet another piece of software for you to provision, deploy, and maintain. Worse, they often just don’t work. Remote firewalls and proxies often block calls and when calls are completed the quality is poor.

    WebRTC makes life much, much easier.

    WebRTC is built directly into your browser which allows you to communicate with ease. There …

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  • By Rob Spectre
    Getting Started Placing Outbound Calls with Twilio Elastic SIP Trunking and FreeSWITCH fslogo

    A couple of weeks ago we announced the public beta of Elastic SIP Trunking, a new way to connect your SIP gear to the world through Twilio. With Elastic SIP Trunks, you can say sayonara to artificial constraints to scaling and pricing shenanigans. We think this new way of consuming SIP connectivity offers longtime VoIP network administrators and engineers an instantly provisioned, powerfully resilient alternative to the SIP trunk.

    One of the more frequent requests we received after opening the Elastic SIP Trunking beta was how to connect an Elastic SIP Trunk from Twilio to FreeSWITCH, the popular open source SIP platform.  Let’s find out how to do that together.

    How It Works

    A Twilio SIP Trunk provides a domain to connect your SIP switching equipment to Twilio. During our public beta, Elastic SIP Trunks only provides termination service, which is to say you can only place outbound …

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  • By Twilio
    TwilioCon 2013: Announcing Picture Messaging, Price Drop, Business Critical Apps and More TwilioCon 2013 Videos

    Today kicks off the third annual TwilioCon, a gathering of the people who are redefining human interaction in every area of business, social good and general hackitude. Our CEO Jeff Lawson took the stage this morning, looking forward to APIs as the new dial tone, with the Software People as the innovators driving the change. You are building the future of your industries, and we’re building the products you need to reach more geographies around the world, and expand your success. We’re so excited to announce a flurry of new products to power your business including Picture Messaging, Twilio SIP, new developer tools to help you build and maintain business critical apps, and drop in price.

    Twilio Picture Messaging: When Words Are Not Enough

    twilio_product_mms-icon_02-picsCombine the power of an image with the reach of sending a text. Introducing Picture Messaging for Twilio Short Codes to send and receive pictures …

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  • By Jonathan Gottfried
    Build a Twilio Hard Phone with SIP from Twilio, Raspberry Pi, Asterisk, FreePBX, and the Obihai OBi100 Twilio Bug Logo

    This post used the Dial and SIP TwiML verbs and the Twilio Message Rest API

    If you have worked with Twilio before, you have surely heard that sweet, sweet ring of your phone many times. But today, we are entering uncharted territory – you are going to learn how to make a phone ring without it even being connected to a traditional phone network! All you need are some simple pieces of hardware and that old landline phone that got shoved into the back of your closet years ago.

    Twilio Hard Phone
    Twilio Hard Phone

    Now, you may have seen our previous Arduino-focused tutorials on building your own Twilio Robot and automating your home with Twilio SMS but today we are going to try something new and use the amazin …

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  • By Devin Rader
    Trying Out SIP From Twilio Using FreeSWITCH Twilio Bug Logo

    Twilio recently introduced the new noun which lets you directly dial a SIP server from your Twilio app. But what if you don’t have a SIP server? In this post I’ll show you how you can set up and use FreeSWITCH, a free, cross platform and open source communication server that includes SIP capabilities, to try out the noun.

    A Quick Intro to SIP

    Before you get started setting up the FreeSWITCH server, it’s useful to have at least a cursory understanding of what SIP is. SIP, or session initiation protocol, is a common protocol used by IP Telephony equipment and software to create and manage communication sessions between two parties. It’s similar to HTTP in that it uses a request/response transaction model and borrows elements from HTTP like headers and response codes. SIP also draws from the SMTP protocol as well using the familiar user:pass@host:port format to …

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  • By Twilio
    Teach Your Old Box New Tricks: Introducing SIP from Twilio Twilio Bug Logo

    SIPPPPPPToday, we are happy to announce from Twilio, allowing companies to receive incoming calls by connecting Twilio to their existing SIP infrastructure. This new capability enables companies to quickly and easily modify their communications processes using the Web programming language of their choice, and to shorten development cycles that, in the past, required software updates and hardware changes.

    With from Twilio, companies can extend the life of their existing SIP infrastructure, and bring new communications capabilities to their networks by connecting Twilio directly to legacy systems. from Twilo also allows companies to transition their application logic to the cloud, without having to update or reconfigure hardware.

    Since launching our public beta, we’ve seen companies of all shapes and sizes, such as RealPage and Corvisa, adopt from Twilio. Many of them have existing PBXs or other SIP hardware, some are developers looking to build new technologies on top of SIP, and …

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  • By Twilio
    Sip from Twilio is here, Sign up for the Beta Twilio Bug Logo

    You shared your enterprise challenges with us and expressed what you wanted, and we listened. Today we are opening beta of the latest  from Twilio capability, allowing you to cloud-enable your existing telecom infrastructure with Twilio.

    This new feature allows companies to connect their SIP gateways directly to the cloud, with Twilio. Therefore, companies who have heavily invested in very expensive telecom hardware can extend the life of it, and connect calls directly from Twilio to their SIP gateway.

    What Can You Do with from Twilio?

    Send traffic to any SIP endpoint. This allows you to pass arbitrary data back and forth from your Twilio application to your SIP gateway. You can make your routing decisions on the fly and this information can be set at runtime. has built in support for failover, retries and weighted routine priorities, as well as supports the standard SIP security standards.

    Using customer SIP …

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