Welcome!

Linux Authors: Pat Romanski, Patrick Carey, Yeshim Deniz, Peter Silva, Glenn Rossman

Related Topics: Linux, Wireless

Linux: Article

Asterisk: Getting Connected

Part 2: A step-by-step guide

In December's column, we installed the Asterisk PBX and configured two IP phones as extensions. This month, we'll connect our PBX to the telephone network for incoming and outgoing calls and set up the Digital Receptionist to route our incoming calls.

Connecting Asterisk to the Telephone Network
Asterisk supports a myriad of ways to connect to the public telephone network. Asterisk provides standard technologies such as IAX (Inter-Asterisk-eXchange), SIP (Session Initiation Protocol), and PRI (with appropriate hardware). We'll be connecting with IAX because it's simple and widely supported by VoIP providers.

Choosing a VoIP Provider
We'll be using VoIP services provided by Blue Networks, Inc., because it offers the best mix of pricing, support, and connectivity. Blue Networks also has online sign-up and a no-nonsense free trial.

Head over to www.sellVoIP.net/ and click on "Free Trial." Blue Networks will send your username and password to the e-mail address you supplied during sign-up.

Your VoIP experience can be affected by many variables. Network latency and reliability issues between your Asterisk server and your provider's gateway are the most critical factors. Luckily, Blue Networks has multiple gateways and finding one with the least latency is simple.

To determine which gateway to use, log into your Asterisk@Home machine either from the console or with a secure shell. Once logged in, issue the following command:

[root@asterisk1 ~]# ping -qc5 miaiax1.sellVoIP.net

After a few seconds, you should see ping results similar to:

PING miaiax1.sellVoIP.net (69.25.180.232) 56(84) bytes of data.

--- miaiax1.sellVoIP.net ping statistics ---
5 packets transmitted, 5 received, 0% packet loss, time 4004ms
rtt min/avg/max/mdev = 38.139/39.095/40.131/0.744 ms, pipe 2

Make a note of the average ping time. In this case, it's 39.095 milliseconds. Run the same ping for seaiax1.sellVoIP.net and nyiax1.sellVoIP.net, then log out. We'll use the server with the lowest average ping time. In my case, miaiax1.sellVoIP.net was the fastest to respond.

Let's configure Asterisk to connect to the fastest gateway and make a couple of test calls.

In AMP, click on Setup, then Trunks. Click on "Add IAX2 Trunk." We'll use the account number "12345" and the secret "mysecret" in this example. Replace these with the account number and secret you got in the e-mail from Blue Networks.

In the "Outgoing Settings" section, we'll add the following:

In Dial Rules, add:

Replace 919 with your local area code. Asterisk will automatically dial this area code whenever a number dialed doesn't include one.

At the bottom of the page, add the following to the "Registration" section:

Remember to replace "12345" and "mysecret" with the IAX username and secret from your sign-up e-mail. When complete, click on "Submit Changes."

Next, click on "Outbound Routing." Select the default route of "0 9_outside." In the section "Trunk Sequence" select the IAX2 route we added above, then click "Submit Changes" and click on the red warning to make your changes take effect, see below.

You should now be able to make phone calls! Remember, since your trial account has a 10-cent balance, your phone call will be limited to a few minutes. Also, always dial 9 and then the number.

To get a phone number (called a DID for "Direct Inward Dial"), you'll have to sign into the SellVoIP Portal (www.sellVoIP.net/portal/) and add funds to your account. You'll then click on "Add DID" and select the DID from the list. At the time of this writing, there are several dozen toll-free numbers available, as well as numbers in various area codes throughout the country. If your area code isn't available, request it in a support ticket.

Once you have a DID, configuring Asterisk to use it is quite simple.

Click on Trunks then click on the SellVoIP trunk we just added for outbound calls. In the section "Incoming Settings" enter your IAX username. In User Details, add the following:

Let's also set our outbound caller ID to this DID. Do this by putting the 10-digit number in the "Outbound Caller ID" field.

Click "Submit Changes," then click the red banner to make those changes take effect.

Configuring the Digital Receptionist
What use is a fancy PBX without being able to route calls? The Asterisk Management Portal (AMP) lets us route inbound calls to the Digital Receptionist, directly to an extension, to a ring group, or a call queue. It will also let us specify different options for "after hours" calls.

We'll configure the Digital Receptionist to handle our incoming calls. Before we record any prompts or greetings, we should take a few minutes to sketch out our requirements and user experience.

Our example company, Spatula City, has a receptionist who should always be reachable by dialing "0." There are only two extensions, so it isn't necessary to configure a company directory. We want the caller to be able to reach our Sales and Customer Service departments through the menu. Our main menu should sound something like:

"Welcome to Spatula City! If you know your party's extension, please enter it now. For the sales department, press one. For customer service, press two. For the operator, press zero."

In AMP, click on Digital Receptionist. The Receptionist will need to know your extension to record menu items.

AMP gives us the option to record our prompt over the phone or upload it as a WAV file. Let's record the prompt through the telephone by picking it up and dialing *77 and reading the welcome message above. You can dial *99 to listen to the recording and *77 again to re-record.

Once the recording is complete, we need to name and describe it:

After clicking Continue, AMP needs to know how many options there are on the menu we just recorded. Enter "3" here.

Spatula City is a small operation. It has a bookkeeper in the back at extension 200. She's also the operator. There's one person dedicated to sales and customer service at extension 201. Our call routing is simple:

Finally, we have to tell Asterisk to use this Digital Receptionist for incoming calls. In AMP, click on Incoming Calls. Spatula City wants the Digital Receptionist to handle incoming calls all the time, even when the store is closed. The easiest way to do this is to set the Digital Receptionist to "Spatula City Main" for regular hours and force regular hours as shown below.

Testing the Receptionist
Asterisk@Home can simulate an incoming call from any extension by dialing 7777. After dialing, you should hear the main menu presented by the Digital Receptionist.

More Stories By Stephen Misel

Stephen Misel has been developing Linux-based applications for over 10 years. He is the owner of Misel Consulting, LLC, a Voice-Over-IP consultancy.

Comments (1) View Comments

Share your thoughts on this story.

Add your comment
You must be signed in to add a comment. Sign-in | Register

In accordance with our Comment Policy, we encourage comments that are on topic, relevant and to-the-point. We will remove comments that include profanity, personal attacks, racial slurs, threats of violence, or other inappropriate material that violates our Terms and Conditions, and will block users who make repeated violations. We ask all readers to expect diversity of opinion and to treat one another with dignity and respect.


Most Recent Comments
SYS-CON Italy News Desk 02/09/06 09:33:26 AM EST

In December's column, we installed the Asterisk PBX and configured two IP phones as extensions. This month, we'll connect our PBX to the telephone network for incoming and outgoing calls and set up the Digital Receptionist to route our incoming calls.

@ThingsExpo Stories
The Internet of Things is a misnomer. That implies that everything is on the Internet, and that simply should not be - especially for things that are blurring the line between medical devices that stimulate like a pacemaker and quantified self-sensors like a pedometer or pulse tracker. The mesh of things that we manage must be segmented into zones of trust for sensing data, transmitting data, receiving command and control administrative changes, and peer-to-peer mesh messaging. In his session at @ThingsExpo, Ryan Bagnulo, Solution Architect / Software Engineer at SOA Software, focused on desi...
"At our booth we are showing how to provide trust in the Internet of Things. Trust is where everything starts to become secure and trustworthy. Now with the scaling of the Internet of Things it becomes an interesting question – I've heard numbers from 200 billion devices next year up to a trillion in the next 10 to 15 years," explained Johannes Lintzen, Vice President of Sales at Utimaco, in this SYS-CON.tv interview at @ThingsExpo, held Nov 4–6, 2014, at the Santa Clara Convention Center in Santa Clara, CA.
"For over 25 years we have been working with a lot of enterprise customers and we have seen how companies create applications. And now that we have moved to cloud computing, mobile, social and the Internet of Things, we see that the market needs a new way of creating applications," stated Jesse Shiah, CEO, President and Co-Founder of AgilePoint Inc., in this SYS-CON.tv interview at 15th Cloud Expo, held Nov 4–6, 2014, at the Santa Clara Convention Center in Santa Clara, CA.
SYS-CON Events announced today that Gridstore™, the leader in hyper-converged infrastructure purpose-built to optimize Microsoft workloads, will exhibit at SYS-CON's 16th International Cloud Expo®, which will take place on June 9-11, 2015, at the Javits Center in New York City, NY. Gridstore™ is the leader in hyper-converged infrastructure purpose-built for Microsoft workloads and designed to accelerate applications in virtualized environments. Gridstore’s hyper-converged infrastructure is the industry’s first all flash version of HyperConverged Appliances that include both compute and storag...
"People are a lot more knowledgeable about APIs now. There are two types of people who work with APIs - IT people who want to use APIs for something internal and the product managers who want to do something outside APIs for people to connect to them," explained Roberto Medrano, Executive Vice President at SOA Software, in this SYS-CON.tv interview at Cloud Expo, held Nov 4–6, 2014, at the Santa Clara Convention Center in Santa Clara, CA.
Today’s enterprise is being driven by disruptive competitive and human capital requirements to provide enterprise application access through not only desktops, but also mobile devices. To retrofit existing programs across all these devices using traditional programming methods is very costly and time consuming – often prohibitively so. In his session at @ThingsExpo, Jesse Shiah, CEO, President, and Co-Founder of AgilePoint Inc., discussed how you can create applications that run on all mobile devices as well as laptops and desktops using a visual drag-and-drop application – and eForms-buildi...
We certainly live in interesting technological times. And no more interesting than the current competing IoT standards for connectivity. Various standards bodies, approaches, and ecosystems are vying for mindshare and positioning for a competitive edge. It is clear that when the dust settles, we will have new protocols, evolved protocols, that will change the way we interact with devices and infrastructure. We will also have evolved web protocols, like HTTP/2, that will be changing the very core of our infrastructures. At the same time, we have old approaches made new again like micro-services...
Code Halos - aka "digital fingerprints" - are the key organizing principle to understand a) how dumb things become smart and b) how to monetize this dynamic. In his session at @ThingsExpo, Robert Brown, AVP, Center for the Future of Work at Cognizant Technology Solutions, outlined research, analysis and recommendations from his recently published book on this phenomena on the way leading edge organizations like GE and Disney are unlocking the Internet of Things opportunity and what steps your organization should be taking to position itself for the next platform of digital competition.
The 3rd International Internet of @ThingsExpo, co-located with the 16th International Cloud Expo - to be held June 9-11, 2015, at the Javits Center in New York City, NY - announces that its Call for Papers is now open. The Internet of Things (IoT) is the biggest idea since the creation of the Worldwide Web more than 20 years ago.
As the Internet of Things unfolds, mobile and wearable devices are blurring the line between physical and digital, integrating ever more closely with our interests, our routines, our daily lives. Contextual computing and smart, sensor-equipped spaces bring the potential to walk through a world that recognizes us and responds accordingly. We become continuous transmitters and receivers of data. In his session at @ThingsExpo, Andrew Bolwell, Director of Innovation for HP's Printing and Personal Systems Group, discussed how key attributes of mobile technology – touch input, sensors, social, and ...
In their session at @ThingsExpo, Shyam Varan Nath, Principal Architect at GE, and Ibrahim Gokcen, who leads GE's advanced IoT analytics, focused on the Internet of Things / Industrial Internet and how to make it operational for business end-users. Learn about the challenges posed by machine and sensor data and how to marry it with enterprise data. They also discussed the tips and tricks to provide the Industrial Internet as an end-user consumable service using Big Data Analytics and Industrial Cloud.
Building low-cost wearable devices can enhance the quality of our lives. In his session at Internet of @ThingsExpo, Sai Yamanoor, Embedded Software Engineer at Altschool, provided an example of putting together a small keychain within a $50 budget that educates the user about the air quality in their surroundings. He also provided examples such as building a wearable device that provides transit or recreational information. He then reviewed the resources available to build wearable devices at home including open source hardware, the raw materials required and the options available to power s...
Things are being built upon cloud foundations to transform organizations. This CEO Power Panel at 15th Cloud Expo, moderated by Roger Strukhoff, Cloud Expo and @ThingsExpo conference chair, addressed the big issues involving these technologies and, more important, the results they will achieve. Rodney Rogers, chairman and CEO of Virtustream; Brendan O'Brien, co-founder of Aria Systems, Bart Copeland, president and CEO of ActiveState Software; Jim Cowie, chief scientist at Dyn; Dave Wagstaff, VP and chief architect at BSQUARE Corporation; Seth Proctor, CTO of NuoDB, Inc.; and Andris Gailitis, C...
There's Big Data, then there's really Big Data from the Internet of Things. IoT is evolving to include many data possibilities like new types of event, log and network data. The volumes are enormous, generating tens of billions of logs per day, which raise data challenges. Early IoT deployments are relying heavily on both the cloud and managed service providers to navigate these challenges. In her session at Big Data Expo®, Hannah Smalltree, Director at Treasure Data, discussed how IoT, Big Data and deployments are processing massive data volumes from wearables, utilities and other machines...
"There is a natural synchronization between the business models, the IoT is there to support ,” explained Brendan O'Brien, Co-founder and Chief Architect of Aria Systems, in this SYS-CON.tv interview at the 15th International Cloud Expo®, held Nov 4–6, 2014, at the Santa Clara Convention Center in Santa Clara, CA.
SYS-CON Media announced that Splunk, a provider of the leading software platform for real-time Operational Intelligence, has launched an ad campaign on Big Data Journal. Splunk software and cloud services enable organizations to search, monitor, analyze and visualize machine-generated big data coming from websites, applications, servers, networks, sensors and mobile devices. The ads focus on delivering ROI - how improved uptime delivered $6M in annual ROI, improving customer operations by mining large volumes of unstructured data, and how data tracking delivers uptime when it matters most.
In this Women in Technology Power Panel at 15th Cloud Expo, moderated by Anne Plese, Senior Consultant, Cloud Product Marketing at Verizon Enterprise, Esmeralda Swartz, CMO at MetraTech; Evelyn de Souza, Data Privacy and Compliance Strategy Leader at Cisco Systems; Seema Jethani, Director of Product Management at Basho Technologies; Victoria Livschitz, CEO of Qubell Inc.; Anne Hungate, Senior Director of Software Quality at DIRECTV, discussed what path they took to find their spot within the technology industry and how do they see opportunities for other women in their area of expertise.
While great strides have been made relative to the video aspects of remote collaboration, audio technology has basically stagnated. Typically all audio is mixed to a single monaural stream and emanates from a single point, such as a speakerphone or a speaker associated with a video monitor. This leads to confusion and lack of understanding among participants especially regarding who is actually speaking. Spatial teleconferencing introduces the concept of acoustic spatial separation between conference participants in three dimensional space. This has been shown to significantly improve comprehe...
The Industrial Internet revolution is now underway, enabled by connected machines and billions of devices that communicate and collaborate. The massive amounts of Big Data requiring real-time analysis is flooding legacy IT systems and giving way to cloud environments that can handle the unpredictable workloads. Yet many barriers remain until we can fully realize the opportunities and benefits from the convergence of machines and devices with Big Data and the cloud, including interoperability, data security and privacy.
Performance is the intersection of power, agility, control, and choice. If you value performance, and more specifically consistent performance, you need to look beyond simple virtualized compute. Many factors need to be considered to create a truly performant environment. In his General Session at 15th Cloud Expo, Harold Hannon, Sr. Software Architect at SoftLayer, discussed how to take advantage of a multitude of compute options and platform features to make cloud the cornerstone of your online presence.