Understanding the SIP OPTIONS Request

Several years ago I bought my sons a set of walkie-talkies.

Some of you may remember that for a while they were huge with the teens and tweens. They were on every Christmas and birthday list. Of course, this was before cell phones effectively put an end to the fad.

Personally, I thought they were pretty cool and imagined all the fun I would have had with them back in my younger days. However, I soon learned that with my kids, wanting something and knowing what to do with it are two completely different things.

Instead of all the spy games I had envisioned for them, the vast majority of their conversations consisted of the following:

“Can you hear me?”

“Yes, I can. Can you hear me?”

“I can. Can you hear me now?”

Pretty sad, isn’t it? So much potential in their hands and they wasted it by running around executing quality of service tests.

Which brings me to what I want to write about today – the SIP OPTIONS request.

Related article: Rummaging Through the SIP Closet

OPTIONS allows a user agent (UA) to query another UA or a proxy server as to its capabilities. This allows a client to discover information about the supported methods, content types, extensions, codecs, etc. without “ringing” the other party.

I imagine that when OPTIONS was first defined, the designers of SIP imagined all the great things people would do with it. After all, knowing what the other side is capable of is very powerful. OPTIONS could be used to set button states for the far-end client. For instance, you could gray out the transfer button if the far-end didn’t support REFER. You could also tailor the codecs you advertised if you already knew what the other side supported.

Knowing something about the far-end before you ever attempted a call could lead to a much better user experience.

For example, this OPTIONS message might be used to ask the far-end to respond back with the SDP it would typically send as part of an INVITE-200 Ok sequence.

OPTIONS sip:carol@chicago.com SIP/2.0

Via: SIP/2.0/UDP pc33.atlanta.com;branch=z9hG4bKhjhs8ass877

Max-Forwards: 70

To: <sip:carol@chicago.com>

From: Alice <sip:alice@atlanta.com>;tag=1928301774

Call-ID: a84b4c76e66710

CSeq: 63104 OPTIONS

Contact: <sip:alice@pc33.atlanta.com>

Accept: application/sdp

Content-Length: 0

Note that the Accept header contains the value, application/sdp. This instructs the far-end to return SDP in the 200 Ok.

However, like my kids with their underused walkie-talkies, most implementations use OPTIONS as a SIP ping mechanism. “Are you there?” “Yes, I am.”

For example, when you configure SIP entities in an Avaya Aura Session Manager, there is a section called SIP Link Monitoring. You are presented with a variety of configuration options that allow you to choose how you want to ensure that a configured entity is up and active. This will ultimately result in how frequently OPTIONS messages are sent. If the entity responds with a 200 Ok, it is marked as active. If no 200 Ok is received, it is marked as down.

I have seen the exact same sort of configuration for Acme Packet SBCs. After a quick web search I find similar statements for Cisco, Sonus, AudioCodes, and Microsoft. Clearly, OPTIONS is universally used by everyone for pinging.

Don’t get me wrong.  Pinging is a good thing and I am glad that you can do it with SIP.  I would just like to see OPTIONS used for a little more than “Can you hear me.”  That’s not too much to ask, is it?  Well, is it?

Can’t you hear me?

Can you hear me, now?

* * *

This article originally appeared on SIP Adventures and is reprinted with permission.

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Avaya CS1000 Customers—We’ve Got Your Backs!

We live in the age of “Fake News” and “Alternative Facts.” Depending on where you live and where you stand on various issues, the daily coverage of events can range from annoying to farcical to deeply troubling. Not to be left out, one of our competitors recently published a blog that by any standard meets the “Fake News” criteria. The headline screams “Avaya End of Support for CS1000” and then (surprise, surprise) suggests the path to glory is to move to their solutions. It really is FUD at its best!

Get the Facts about Avaya CS1000

The Avaya Communication Server 1000 remains a fully supported and saleable product. We have been crystal clear with our customers and partners that Release 7.6 is the final feature release and only Service Packs will continue to be issued. As promised, Avaya continues with Service Packs and has done so on a regular basis over the past several years.

We continue to work with our material suppliers, customers and partners to determine the right date for the end of sale and, once the decision has been made, we will make a formal announcement of the EoS date in accordance with our normal polices. Once an EoS date is announced, per our standard Avaya support policies, we will provide support out to at least 2024. Specifically:

  • End of Sale would be followed by one year of Manufacturer Support for software (three years for hardware)
  • That in turn would be followed by five years of Extended Services Support for software (three for hardware)

So we will provide support for a full six years following an End of Sale announcement—which is why I say we will provide support to at least 2024. Note that this is the earliest possible date for the end of support.

Beyond supporting specific dates, Avaya has a number of programs and policies (like the Avaya Software Investment Protection Policy) that provide investment protection for CS1000 customers as they migrate to the Avaya Aura® platform or the Avaya IP Office™ platform. Avaya plans to expand these offers with additional announcements over the next few quarters—details will be widely communicated to our customers.

Feeling better? You should be. Avaya values our CS1000 customer—and all of our customers. It is our intention to remain your trusted partner and supplier of innovative communications and collaboration solutions for many years to come. A big part of that is our drive to provide a path forward for every customer. If you’d like to learn more, please contact your Avaya or partner representative and start a conversation about where Avaya’s latest solutions can take your business.

Avaya. Strong Now. Stronger in the Future.

Avaya Aura® Platform—The Original Pragmatic Hybrid Cloud

In a recent InfoWorld post David Linthicum wrote of “an organic movement driven by rank-and-file enterprise IT people who simply want to solve their issues using the best technology and approach.” Linthicum called this the “pragmatic hybrid cloud.” Reading this from the perspective of someone with decades of experience in the enterprise communications market, my immediate reactions was, “Aha, he’s talking about the Avaya Aura® Platform.” He isn’t, but here I’ll explain why this thought struck me.

Linthicum writes, “What this movement has discovered is that you can combine the public cloud and modernize some of your legacy systems to be more cloudlike.” That is exactly what Avaya customers have been achieving in an evolutionary process spanning almost two decades. Long before the term cloud came into vogue, Avaya customers have been able to gain the benefits of the cloud paradigm while avoiding the need to comprehensively lift workloads to a public cloud provider and the need to wholesale forklift and abandon existing investments.

Today, many Avaya customers—including a large swath of the globe’s most notable organizations in industries ranging from financial services, to healthcare, to government, and many small and medium businesses—process their mission-critical workloads using a combination of premise-based solutions and both public and private cloud-served applications. It is a “pragmatic hybrid” approach that since the mid-2000s has provided these Avaya customers with unparalleled reliability, cost savings, and business agility.

The Avaya Aura Platform is the reason why. Avaya Aura had its genesis in a time tested methodology for allowing geographically distributed organizations to link islands of resources to gain economies of scale. Back in the day, to create either a contact center that followed the sun or a single enterprise communications solution that served the needs of a worldwide workface, expensive dedicated circuits were required. As IP Telephony evolved, companies began to use packet-switched technologies to more cost-effectively link together distant resources into single holistic systems. Rather than centralized in isolated locations, communications applications could now be seamlessly and cost-effectively shared across distances. This made new ways to organize communication assets and the work that depended upon those resources possible.

Avaya’s great insight was to take advantage of the session initiation protocol (SIP). Over time Avaya’s customers have “pragmatically” converted the networking connections of their existing standalone investments to create fabrics of SIP internetworked appliances. The Avaya Aura® Session Manager lets companies treat their owned assets as part of a private cloud and combine those resources with public cloud capabilities both from Avaya and from a growing ecosystem of additional providers. It is a strategy that has resulted in significant cost savings while unleashing new innovation.

Today the Avaya Aura Platform has moved far beyond simply a “pragmatic hybrid” for sharing resources. It has become a strategic tool for many organizations. It gives companies a flexibility and agility to adapt and reconfigure at the speed of business. Avaya Aura has also opened the doors to both internal Avaya inventions and new external development.

Avaya Breeze™ Platform is but the latest application development platform that takes advantage of Avaya Aura. Avaya, Avaya’s customers, and an industry of third-party companies are leveraging Breeze with their own creativity for solving business problems. Breeze allows the creation of unique ways to leverage the inherent capabilities of Avaya products in combination with cloud and third-party capabilities. Whether those assets reside in a private data center, on premises-based servers, or in public clouds, because of the Avaya Aura Platform, the only barriers to progress are the limits of human ingenuity.

Linthicum concluded that, the “pragmatic approach is very sensible. It makes the most of what you have, reducing the need for new resources and letting you transition to the cloud at a pace you can handle, both in terms of cost and time.” Your Path, Your Pace, Your Choice, where have I heard that before? Avaya circa 2004 maybe? Nice to see the industry finally following Avaya’s lead.

 

Zang Serves Up a Special Delivery for Your Mom this Mother’s Day

Mother’s Day is the one day in the U.S. when the most phone calls are made. According to this cool Mother’s Day Facts site, 122 million calls are made to mothers on Mother’s Day in the United States alone. Considering there are only 85 million mothers in the U.S., Mom must be pretty busy taking calls from her multiple children, and Dad must be busy making reservations at the favorite family restaurant (Mother’s Day remains the top holiday for dining out).

To help make sure Mom gets that special call on Mother’s Day, Zang today announced a Zang-built service for those who 1) are multiple time zones away from mom (ie: military, working or studying abroad), 2) just want to send another thoughtful gift to Mom to let her know she’s loved, or 3) frankly, for those who have a track record for forgetting (you know who you are). With the Zang Forget Me Not service, anyone can record a voicemail for their mom before Mother’s Day, designate the date & time the voicemail should be sent, then receive a text confirming the voicemail was delivered. The new service was created using  cloud-based Zang Comms platform as a service, which allows anyone to create communication applications and services just like Forget Me Not.

How does it work, you ask? Simple. First go to www.zang.io/callmom and complete four short steps:

1)  Enter your telephone phone number
2)  Enter recipient’s telephone number
3)  Pick the time you would like the recording to be delivered
4)  Zang Forget Me Not service will then call your phone number for you to record, review and approve your message for delivery.

 

Go ahead—give it a try! It’s just one more surprise you can give Mom this Mother’s Day.