Alan Percy : The SIP Invite
Alan Percy
| Observations by Alan D. Percy on VoIP enabling technology, industry and our personal reach for success.

SIP

SIP Interoperability: Why Is It So Hard To Achieve (Part III)

July 30, 2009

During this last "blogisode" we moved from a discussion about the technology and weakness of the SIP RFCs to what I feel is a far more difficult hurdle, the political challenges with SIP interoperability. As with national and global politics, getting people with diverse needs and existing investments to compromise is a significant challenge.

So how do we break the almost infinite cycle of continuous interoperability testing between the growing number of hardware vendors, software applications and carriers?

One approach that immediately comes to mind is to define a "gold standard" that each of the market participants can test against, and create a predictable level of interoperability assurance between systems.

SIP Interoperability: Why Is It So Hard to Achieve? (Part II)

June 17, 2009

 Earlier this week I shared with you a few thoughts on SIP Interoperability discussing what I felt where the root causes of incompatibility between two or more SIP-based systems.  I clearly hit a raw nerve with a few of you, flooding my email box with your own stories of interoperability issues.   You shared with me your own experiences with registration problems, call transfers, security, message waiting indications, even fax issues.  It seems the couple examples I gave were only the tip of the iceberg.

 

Let's move past the technical issues with SIP Interoperability and talk about a far more difficult challenge - the politics of SIP Interoperability.

 It appears to me that soon after the authors of RFC 3261 finished their work, the fun really started.  As the development teams of the various product and application companies started to build their solutions based on RFC 3261, the looseness of the specification allowed them to make wildly different choices all "within specification".   The result was that you had developers that had invested untold hours of hard work into developing a protocol stack that worked fine in their own lab and with their own products, but had serious interoperability issues with other vendors.  To each of the developers, it appeared that "everybody else screwed up". 

 So now you have a number of over-worked developers that would have to go back into their products and re-work significant parts of their SIP stacks - just because someone else made some bad choices.  The end result is a classic stand-off with each of the vendors saying "we followed the spec, you should change".  So much for "Open and Standard".

 

To make things even more politically complex, many of the vendors are starting to compete in the marketplace, vying for the same markets and customers.  In this competitive environment, interoperability is a double-edge sword.

 Okay, so let's pretend our developers get past their own stubbornness and decide to make some changes to be more interoperable.  Who do you do your interoperability testing with?  Do you test against anyone that comes along?  Or maybe just in cases where "the business case works"?

SIP Interoperability - Why Is It So Hard To Achieve? (Part I)

June 12, 2009

For those of you that have deployed SIP-based solutions or SIP Trunking, there is a pretty good chance that you've had to navigate your way through the maze of SIP interoperability, wondering why it is so difficult to get a straight answer out of anyone on whether two systems will work together or not.

SIP is supposed to be a standard and eliminate many of the challenges with integrating systems from various vendors together, right? If my IP-PBX is RFC 3261 compliant and my SIP Trunking service provider is RFC 3261 compliant, they should just work, correct? Well--maybe or maybe not.

Can Branch Offices Save Money and be Survivable?

May 4, 2009


Branch offices are the life blood for a wide range of businesses. Financial service companies, insurance, retail, education and government vertical markets depend heavily on having a physical presence in the neighborhood of their customers. However, having a physical office means you need a reliable means to communicate with both customers serviced by the office and the employees in the branch office. To date, most branch offices have low-cost stand-alone TDM telephone systems (aka Key Systems) and use the expensive legacy PSTN to make and receive telephone calls between offices and to their customers.   Meanwhile, most businesses today also have some form of IP connectivity for each branch office, whether a private MPLS network or use of the public internet. The IP services are needed for inventory systems, point of sale or email/web.   This situation leads to an opportunity to combine the two networks, leveraging VoIP and SIP to network the branch offices together and reduce operational costs.    Potential areas of savings:
  • Reduction of trunk lines to branch offices
  • Elimination of toll charges for inter-office calling
  • Consolidation of trunking facilities
  • Centralized applications (voice mail, IVR and ACD systems)
  • Easier remote management and elimination of "truck rolls"
  • Improved productivity with Unified Communications capabilities
  With all these areas of potential savings, it should be easy to justify migration to an all SIP-based architecture for branch offices, but there are a few barriers that need to be resolved:
  • Survivability - what happens at the branch if the wide-area network goes down or accidentally cut? An extreme example of this is the outage in San Jose, CA on April 8th, 2009 where a major fiber optic line was cut by vandals.
  • Local Numbers - will you still have the same local numbers that long-established customers have on their prescription bottles or refrigerator magnets?
  • E911 - if there is an emergency, will the first responders be directed to the right facility?
  • Broadband Availability? - while quite common in urban and suburban areas, wireline broadband is either very difficult to get or very expensive in most of rural America. Common wireless technologies including EVDO, WiMax and satellite are not conducive to voice traffic and may insert significant latency or jitter.
  The challenge is to find an architecture that balances the cost savings of SIP-based branch office communications with the needs for reliability and maintaining local access.  
A Fully Distributed architecture with separate stand-alone equipment at each site pushes all the intelligence to the branch offices, but doesn't consolidate resources or save enough money to make it viable over the long haul. Many of the smaller IP-PBX or communications appliance vendors are touting this architecture, mostly because customers are used to this from the key system days.  
A Fully Centralized architecture moves all the intelligence to the core with a large IP-PBX or Softswitch at the headquarters or hosting site and just network equipment and IP phones at the branches. This architecture dramatically reduces costs of the equipment at the branches, but is highly dependent on the quality and stability of the WAN. Local number portability and E911 questions create other problems.  
It seems that a hybrid architecture that combines the the best attributes of the fully distributed and fully centralized is much more realistic and is becoming the reference for most network designs going forward. This architecture puts some intelligence at the branch offices, which could include either a small IP-PBX or SIP Proxy to handle intra-office calls or emergency calling. The large centralized IP-PBX or Softswitch would manage inter-office traffic. Other application components including voice mail, local IVR and ACD at the branch offices off-load these services from the central site and allow them to operate with less expensive WAN services or in cases of a WAN failure.  
Where the dramatic cost savings of this architecture comes to fruition is when the data connectivity, routing, security and application features come together in a single appliance at the branch. A number of solution vendors (including AudioCodes) are starting to leverage Multi-Service Business Gateway (MSBG) devices to host a small version of their application, a SIP proxy or other intelligence for the branch office along with the data connectivity infrastructure. MSBGs are ideal for "greenfield" branch office deployments where new offices or complete network renovations are in process.  Benefits to the enterprise include a dramatic simplification of installation and maintenance across a large number of remote sites.   So, getting back to the original question: "Can branch offices save money and be survivable?" The answer is "yes", consolidating voice and data traffic on to one network and reducing maintenance costs for older equipment can definitely reduce operating costs.




SIP Trunking - Bundled or BYO?

April 27, 2009

While on the road this spring I had a number of very active conversations with our partners and customers about the delivery mechanisms, services and bundling of SIP Trunking here in the US.  It seem there are some patterns that I thought would be useful to share.

First I'm going to assume that you know that SIP trunking is a replacement for legacy TDM trunking lines that connect various size enterprises to the public network.  SIP trunks offer similar services, but instead of using dedicated TDM T1/E1 or analog telephone lines, the voice traffic is transported over IP-based data circuits.  SIP is used as the signaling protocol, controlling the start and stop of each voice conversation, associated caller ID and other enhanced services.

SIP trunks are not all created equal though - there are some very significant differences in the way they are sold and the services they support. I could spend months going into all the various technical and business model differences between the vendors, but today I'm just going to concentrate on the different ways they are delivered to the customer.

Tightly Bundled SIP Trunks
These typically are tightly tied to data services that would come from the service provider.  In this case, the service provider requires that you use their data infrastructure to carry the SIP trunks. They arrange for the last mile circuit, provide all the equipment and provide the services with one bill. The logic the service provider uses for this offering is that unless they can control the data infrastructure end-to-end, they can't guarantee the voice quality.  The biggest benefit of the bundled services is that it gives the customer "one throat to choke" if there are issues with the service or quality of calls.  

However, I've heard some push-back from customers on this "take it or leave it" business model, requiring that they buy both the broadband and voice services together.  In some cases the cost reduction doesn't justify the complexity and risk.  What if the enterprise already has an established relationship with a broadband provider and is under contract?  Do they need to pay to break the contract?  What about the risk of potential disruption while migrating both the voice and data services to a new service provider?  Can the service provider deliver both voice and data services to all my offices?

In the end, it seems tightly bundled SIP trunks are best suited to greenfield deployments within the service provider's area of coverage.

BYOBB SIP Trunks
The opposite of the above separates the SIP trunks from the broadband delivery to the customers site.  In this case, SIP trunks are a service that the customer uses on their existing or upgraded broadband facilities.  Thus the term Bring Your Own BroadBand (or BYOBB) was born.

The advantages of this service offering is that it can be offered virtually everywhere where there is sufficient broadband and it can be layered on top of existing Internet services. This allows an enterprise to partially or fully migrate to SIP trunking without disrupting their current data services.  For some enterprises, they have already done extensive upgrades to their data infrastructure and SIP trunking is just another application that was already budgeted for well in advance.  The ability to choose multiple SIP trunking services separately from the broadband is a powerful tool when negotiating on a service contract, especially when looking for local numbers outside the US.

Many of the BYOBB SIP trunking service providers let you choose the equipment at your premise.  From WAN access, the router, security solution and the media gateway.

On the downside, I've heard some debate about the validity of the methods used to test the existing broadband circuits and how to prove compliance with service level agreement terms, especially with voice quality.  Then there is a long-term problem of the broadband carrier managing the traffic inside their network.   If it works today, will it work tomorrow as they add new customers? It's important to choose a service provider that supports built-in quality monitoring capabilities, including RTCP-XR which reports real-time R factor scores on voice quality.



















Can You Have your Cake and Eat it too?
There are a number SIP trunking service providers that try to ride the fence and will offer you either a bundled service or unbundled, based on your individual situation.  However, it sounds like you will get pressured hard to take the bundled service to control quality and "maximize value".  The bundled services are frequently wrapped up in one-size-fits-all packages that are a lot easier for them to sell, install and service.  The only question is:  Do you fit the one size they are offering?

What's Right for You?
Well, it really depends on a few factors:
  1. How much do you value having "one throat to choke"?
  2. How much bandwidth do you currently have and is it voice-ready?  If you already have a good broadband provider, use it!  If not, maybe a bundle would get both upgraded at once for a good price.
  3. Are you under contract with either a voice or data service provider?  Does it make sense to break either or both the contracts?  Work the numbers - then decide.
  4. How much control do you want over the equipment and services?  If you could care less, just go with a bundle.  The more you know, the more control over the services and equipment you will invariably want - go with unbundled services.
  5. Are you planning a slow migration with a few circuits to start or are you going to cut over all at once?  Complex and gradual cut-overs need more control.
Hopefully this background on the range of SIP trunking offerings will help you with your adoption.  Make sure you ask the right questions and consider your individual situation before signing anything!





Distributed Enterprises - Can they save money and be reliable?

April 13, 2009

Over the last few weeks, I've spent quite a bit of time talking with a variety of partners about leveraging SIP in large enterprise deployments and specifically the architectures used to support branch offices.  When I first starting working on this problem, my original reaction was "Simple, just put in a softswitch and connect all the sites together via SIP - Done".  

It turns out it's not that easy.  From listening to our partners and their customers, I have learned there are a few real challenges they deal with when deploying communications systems into distributed branch office situations:

First you need to get good quality broadband to every one of your branch offices, which is hard to do once you leave the urban/suburban rings of most cities.  Getting voice-grade  broadband to remote offices in rural America can be very expensive and wipe out any potential cost savings.  Consumer grade broadband is easier to get, but even then not predictable enough for commercial applications.

Second is the question of reliability, which was recently demonstrated by the massive Internet outage in San Jose. What will happen to your business if the broadband connection to the site is cut?  Do you just close for the day and kiss off the revenue?

Third is network traffic optimization - does every call really need tie up your broadband service?  Is there a more efficient way to leverage the expensive and shared broadband that services the branch offices?

The solutions seems to be in an architecture that fits somewhere between the two extremes of fully centralized and fully distributed, but exactly where depends on the individual business.

To discuss these challenges and some potential solutions, I've invited Bruce Mazza, Director of Branch Office Solutions for Avaya to join me in a live webinar on Tuesday, April 14th at 2 PM.  I encourage you to Click here to register for the live event or listen to an on-demand recording of the event.











Avaya Aura Launch - Leveraging SIP

April 1, 2009

Yesterday's big news here at VoiceCon Orlando 2009 was the launch of Avaya Aura, a new SIP-based architecture and strategy from Avaya that  "simplifies complex communications networks, reduces infrastructure costs and quickly delivers voice, video, messaging, presence, Web applications and more to employees anywhere."

As Kevin Kennedy, president and CEO, Avaya noted in both his keynote address and press materials:  "We've seen some organizations use SIP routing to reduce trunking costs by 20 percent to 60 percent. With this new architecture, for the first time, the way we communicate is defined by the applications and the user, not the network."

Bruce Mazza, Director of Branch Office Solutions and Alon Waks, Solutions and Product Marketing for Avaya gave me a quick tour and demo of the Remote Branch portion of the solution showing how branch offices leverage  AudioCodes MediaPack analog gateways to provide survivability in situations where the wide-area-network were to fail or become unavailable.

In addition to survivability, the AudioCodes MediaPack gateways can provide connectivity to analog phones, fax machines and other legacy devices in remote branches.

This announcement highlights one of my key strategic visions of the power of SIP, connecting diverse and distributed businesses together at far lower costs than using the PSTN to call inter-branch.  

I'll be joined by Bruce Mazza to discuss the new Avaya Aura strategy and branch office survivability in an upcoming webinar that I'll be hosting.  Click here to register for the event









Discussion with Bruce Mazza on SIP-enabled Distributed Enterprises

March 23, 2009

AudioCodes has been working closely with Avaya for a number of years and as part of our exhibition at VoiceCon Orlando next week, I've invited Bruce Mazza, Director of Branch Solutions at Avaya to present during our AudioCodes / ScanSource Solutions Theater.  Avaya's Branch Office solution leverages SIP to connect remote branch offices to regional offices, which reduces operating costs for banks, insurance, retail and government customers that frequently have dispersed remote offices.

AP: Bruce, thanks again for joining us in Orlando. What's the title/topic of your presentation?


BM:  "Distributed Enterprises -Reduce Operating Costs and Maintain Reliability"   AP: How does the Avaya application help enterprises in this difficult economy?    


BM: The joint solution from Avaya and AudioCodes will help medium and large businesses with many small branch office locations to reduce the cost of deploying and managing communications by centralizing trunking access and reducing monthly fees, reducing inter-enterprise long-distance fees by running voice over the customers WAN, centralizing management to reduce overhead costs, all while increasing branch user productivity through value-added UC applications.   Since the solution is survivable with the AudioCodes SAS capability matched with Avaya's SIP 96xx phones, branch office users can have the assurance of business continuity.   AP: What will this solution mean to VARs that service companies with remote branches?  


BM:  VARs will enjoy the opportunity to address medium and large enterprises with a full complement of branch solutions from Avaya, and to address the very small branches that are so prevalent with the survivable SIP branch solution from AudioCodes and Avaya.  Opportunities exist for product sales in Data Centers, and Branches, as well as services to design, build, and deploy customers branch networks.   AP: What about the Avaya strategy is different from before the economy went sour?   


BM: Frankly, we had planned to introduce this solution before the economy went sour. Now customers will be even more compelled to implement the solution to gain the OPEX savings.   AP: Share with us who would get the most out of your presentation at VoiceCon?    


BM: I believe IT Manager, Telecom Directors and CIOs of companies that numerous remote branches would find the session very helpful.      AP :Where would someone learn more about the Avaya Branch Office solution?    


BM: We'll have information at both the Avaya and AudioCodes booths with live demonstrations that can be seen by attendees.
Bruce's presentation is scheduled for Tuesday, March 31st at 2:00 PM EDT in the AudioCodes / ScanSource Solutions Theater within booth #931.

Did I mention that by attending you can win one of 14 iPod Touch PM3 players that we are giving away?














Interview with Rick Q. Chin @ Interactive Intelligence

March 19, 2009

Another interesting presenter and topic that I am looking forward to at the AudioCodes / ScanSource Solutions Theater at VoiceCon Orlando is Rick Q. Chin from Interactive Intelligence.  AudioCodes has been working with Interactive Intelligence since the very earliest days of their Customer Interaction Center, one of the premier SIP-based contact center solutions on the market.

AP: Rick, what's the title/topic of your presentation? 


RC: The presentation I'll be bringing is 'Improving the Customer Experience with CIC' and it discusses how to help companies win and keep customers


AP: How does Interactive Intelligence CIC help enterprises in this difficult economy? 


RC: Increases efficiency, effectiveness, and utilization of resources, improves customer service and increases customer satisfaction, provides lower operating and ownership costs

AP: Is there an opportunity for Value Added Resellers (VARs) that would be at the event to leverage with your solution? 


RC: Absolutely, Yes they would get a lot from my presentation.

 AP: What about the Interactive Intelligence strategy is different from before the economy went sour? 


RC: Focusing on communicating the value and high ROI of our completely line of applications, unique truly all-in-one product, and the higher productivity and effectiveness it provides vs.

Interview with Joel Maloff @ BandTel

March 11, 2009

 As noted in yesterday's post about VoiceCon, our opening speaker in the AudioCodes / ScanSource Solutions Theater will be Joel Maloff, Vice President of Marketing for BandTel.  BandTel is a pure SIP Trunking service provider that utilizes AudioCodes gateways to connect their services to end-customer TDM PBXs or other equipment.  Joel was kind enough to spend a few minutes with me yesterday, providing a preview of what to expect in his presentation at VoiceCon.

AP: Can you share with us the title and topic of your presentation?


JM: Sure, the title is 'SIP Trunking - Ready for Prime Time '

AP: How does SIP Trunking help enterprises in this difficult economy?


JM: SIP trunking has two immediate benefits for enterprises, especially in light of economic conditions. The first is the ability to broaden an enterprise's reach via the use of remote local telephone numbers. For example, an enterprise that is forced to consolidate and close down physical locations can retain those telephone numbers and have them ring into one or more centralized facilities. In this way, local identification is retained, operations are consolidated, and costs can be dramatically reduced.





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