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"sip" posts

  • By Madhu Mathiyalagan
    Transfer calls with context using SIP Refer from Twilio and SIP UUI Header Transfer calls with context using SIP Refer from Twilio and SIP UUI Header

    Today we are thrilled to announce that SIP Refer from Twilio is now generally available for call centers looking to transfer calls from Twilio to their SIP infrastructure. This enables call centers to save money on their calls by removing Twilio from the call path. When used in conjunction with SIP UUI Headers, a feature released this summer, context from Twilio can be passed along with the SIP Refer.

    Call Centers can use SIP Refer and SIP UUI Headers to transfer calls from Twilio to their internal SIP infrastructure, while maintaining call context, in order to transfer the call back to their IP infrastructure and handle sensitive information internally.

    Transfer the call back to your IP infrastructure

    When a customer calls into a contact center through Twilio to speak with Agent 1, Agent 1 can now transfer the call and pass relevant information to Agent 2 through their internal SIP …

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  • By Alan Klein
    A Step-by-Step Guide to Set Up Twilio Elastic SIP Trunking Copy of Generic Blog Header 2-3.png

    In my last blog post, Registering a SIP Phone Directly to Twilio (and so much more...), we set up a Twilio Programmable Voice SIP Domain and registered our SIP softphones directly to Twilio. This let us place and receive calls to the Public Switched Telephone Network (PSTN) but more importantly, set up the foundation for building creative applications which intelligently route calls using dynamically returned Twilio Markup Language (TwiML).

    In this post we’ll provide a step-by-step approach to connect your SIP element – IP-PBX, SIP-PRI IAD, SBC, etc. – to Twilio’s Elastic SIP Trunking product. By the end of this post, you’ll have your existing communications infrastructure connected through Twilio and ready to layer on a number of Twilio’s other features.

    At its most basic level, Twilio Elastic SIP trunking provides dynamic trunking capacity to place and receive pay-as-you-go phone calls through Twilio. Twilio’s network …

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  • By Alan Klein
    Registering a SIP Phone Directly to Twilio (and so much more...) Sl2wfrJ5aA9RwXwPmthRlZdT9FnZmsiEAYFdlVUQ5C8KQfEWVaHhxkipFOx_DwRAwEBVlcKcLvmUOrJrzO8aZW5WsjOfKvBh54q7Oh50m2cLpIxYRbxXoFsULFNNCP3b5nWxrnW2

    Twilio Programmable Voice SIP Domains, sometimes referred to as SIP Interfaces, allow you to place and receive voice calls using a standards based SIP endpoint by registering directly with Twilio.

    Along with the ability to register directly with Twilio, you have the flexibility to choose the termination transport. This may include the traditional public switched telephone network (PSTN), another registered SIP device (often referred to as a SIP user agent [UA]), or even a Twilio Programmable Voice SDK endpoint. Connect all the things, indeed!

    In this blog post we will:

    • Register a SIP phone directly to Twilio
    • Place and receive calls from a registered SIP phone
    • Cover recommended design approaches
    • Provide two different methods for delivering SIP Domain phone calls
    • Discuss the benefits and current limitations using Twilio SIP Domains

    Prerequisites to working with SIP Domains and Twilio

    To accomplish the tasks in this blog post you will …

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  • By Humberto Reyes
    Introducing IP ACL CIDR Block Support - SIP Interface and Elastic SIP Trunking acl_icon (1).png

    A new control to improve security and save you time.

    Today Twilio is announcing an enhanced security control at the edge of the network to give customers a quick and easy way to block communications from rogue hosts.

    We are excited to introduce, CIDR Block support for IP Access Control List (ACL) used in SIP Interfaces and Elastic SIP Trunking products.  

    This feature allows you to define an IP address range with a network prefix improving security, saving time and making IP ACLs more scalable from both the Console and the API.

    Getting started

    The following animation shows you how easy it is to start using CIDR Blocks on your Elastic SIP Trunks, simply follow along:


    As you can see once you enter the IP Address and select the slash notation it will show you the IP Address Range.  If you are looking to add just one IP Address to …

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  • By Annie Benitez Pelaez
    Elastic SIP Trunking: Call Transfer via SIP REFER logo

    If you’re running a multi-site Contact Center and you need to transfer a call from one agent to another agent in a different location, you can now send Twilio a SIP REFER message requesting that transfer.

    About call transfers

    A call transfer is just what it sounds like: It’s when you transfer a customer’s call from one call center agent to another. You might need to initiate a call transfer for several reasons, such as when a customer requesting to speak to the manager. Quick, easy call transfers are a necessary function in today’s business telecom environments.

    When an agent presses the “Transfer” button on a SIP-enabled IP phone, the phone issues a SIP REFER method requesting the call to be transferred to a third party using the contact information provided in the request.

    A very common type of call transfers is “blind” transfers. Blind transfers occur when a call …

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  • By Nayana Srivastava
    Announcing Voice Insights for Elastic SIP Trunking and SIP Interface Screen Shot 2018-07-01 at 1.22.25 PM

    Voice Insights is a call data analytics engine that provides details ranging from real-time metrics for individual calls to account-wide historical trends and aggregates to assist in diagnosing call performance problems, investigating call quality reports, and identifying emerging issues. Voice insights already includes WebRTC and Carrier Insights and today, we are excited to announce that Elastic SIP Trunking and SIP Interface Insights are now also available, in Beta. You can now easily have a deep understanding of your calls when they traverse your SIP communications infrastructure. These insights enable you to have an end-to-end understanding of call quality, no matter how the call is made or received, and help diagnose call establishment and performance issues.

    Using Twilio SIP Insights data, for every SIP call made or received through Twilio, you can analyze call performance from an aggregated view down to granular details about a call. For any given call you …

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  • By Tim Beyers
    How to protect your account from toll fraud with Voice Dialing Geo Permissions 032218_engage_blog-header_02-toll-fraud-phone

    Did you know that International Revenue Sharing Fraud (IRSF), also known as toll fraud, leads to $10 billion dollars in annual revenue losses globally and has grown six-fold in the past five years? Care for a horror story? Read about this seven person architecture firm in Georgia that came to work on a Monday to find a $166,000 bill from their local telecom provider.

    Teams of criminals are continuously looking for ways to exploit your apps by placing calls to their international premium rate numbers – a virtual wire-transfer from your company’s bank account to theirs.

    Now with a few clicks on the Twilio Console, you can take one big step to further protect your application from being the next victim of toll fraud.

    There’s no silver bullet with toll fraud. Before we dive into Twilio’s dynamic solution to prevent toll fraud, it’s important to understand that there …

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  • By Donnie Wang
    SIP Interface adds support for international regions connect-anything

    We’re excited to share that SIP Interface now supports international regions, including North America (Virginia, Oregon), Europe (Ireland), Asia Pacific (Tokyo, Singapore, Sydney), and South America (São Paulo). This means that when you send SIP to Twilio, or receive SIP from Twilio, you can specify the region that’s closest to the location of your communications infrastructure to ensure the best quality of service.

    Sending SIP to Twilio

    To specify the gateway to send SIP traffic to:

    1. Update your IP address whitelist.
    2. Point your communications infrastructure to any of our localized URIs.

    Receiving SIP from Twilio

    To specify the region to receive SIP from Twilio:

    1. Update your IP address whitelist.
    2. Include the region parameter in your SIP URI. This can be done directly in TwiML:

    <?xml version="1.0" encoding="UTF-8"?>
            <Sip>sip:alice@example …
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  • By Annie Benitez Pelaez
    How to Configure Twilio Elastic SIP Trunking with FreePBX SIP Trunking

    Twilio Elastic SIP Trunking is used to connect your IP-based communications infrastructure to the publicly switched telephone network (PSTN), so you can start making and receiving telephone calls to the ‘rest of the world’ via any broadband public internet or private connection. Twilio users often hook Elastic SIP to FreePBX, a web based GUI with an underlying Asterisk based PBX. We took best practices from our users and collected them into a series of video tutorials that give you a step-by-step guide on how you can configure Twilio Elastic SIP with FreePBX.

    Twilio Elastic SIP Trunking has several advantages over traditional SIP Trunking whether you are trying to connect to global telephony network or power notifications systems with unpredictable traffic. One of the biggest advantages is the ease of configuration and complete freedom to manage your SIP connectivity as you choose. The video tutorials below show you how to start …

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  • By Annie Benitez Pelaez
    Introducing SIP Registration sipregistration

    We’re excited to introduce a new way to use the Twilio Voice API – via SIP Registration. Now you can connect your SIP-enabled devices or softphones directly to Twilio and use the Voice API to build nifty call-handling logic. For example, you can get phone numbers in nearly 50 countries for those phones. Then, decide if your phones ring sequentially or simultaneously. You can control call routing from your code, based on day of the week, time of day, or Caller ID.

    SIP Registration is available now and it’s free to register multiple devices per user. That’s enough to make even the most device-crazy person happy. The same Programmable Voice pricing for making and receiving calls will apply. To get started, check out the setup instructions below.

    But first, here are some early examples of how others are using SIP Registration.

    How Contact Centers Use Twilio’s SIP Registration

    Serenova, …

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