John Bartlett is a leading authority on real-time traffic, application performance and Quality of Service (QoS) techniques. He specializes in helping enterprises manage voice, video and data application performance. John has engaged with over 50 enterprises and over 20 network vendors to analyze network performance problems, design network solutions, and support network solutions.
John has 29 years of experience in the semiconductor, computer and communications fields in marketing, sales, engineering, manufacturing and consulting roles. He has contributed to microprocessor, computer and network equipment design for over 40 products. He has been consulting since 1996.
Prior to working as a consultant, John was a founder and VP of Engineering and Manufacturing at Agile Networks, now part of Lucent Technologies. Under his leadership, the company designed and built a high performance Ethernet switch implementing VLANs, and one of the first commercial ATM switches. Both products were successfully introduced to the market and the firm became profitable before it was acquired. Mr. Bartlett also served on the IEEE 802.1 committee during this period, and contributed to the development of the IEEE 802.1P and IEEE 802.1Q standards (priority and VLANs.)
He previously worked for 9 years at Encore Computer, Corp. in engineering and engineering management positions designing networking equipment and large scale multiprocessor systems. At the end of this time Mr. Bartlett was managing 70 engineers across 2 geographic sites.
John also spent six years with Intel Corporation during the early years of microprocessor design and acceptance into the market.
John is a graduate of Dartmouth College, and Dartmouth's Thayer School of Engineering, where he received the Dartmouth Society of Engineers Annual Prize for the quality of his thesis presentation. John is co-owner of a patent in shared memory multiprocessor design.
We are at an interesting transition point here in our understanding of how to manage applications on the IP network.
My contention is that desktop video can deliver great images at much lower bandwidth and in most cases does not require HD bandwidth.
We came up with a model for predicting the number of video conferencing calls per month for a company.
We need a statistical model like Erlang, but with a different set of characteristics so we can accurately estimate the peak bandwidth demand on the network.
Higher utilization means a lower cost per hour of use, and vice versa.
One of the biggest questions for all the approaches is scalability.
The industry needs a new device that is a central resource for bandwidth management within classes of traffic on the network.
My guess is that Cisco will be supporting standards, but not the standards we are using today.
There are enterprises running this architecture today with the help of some third parties providing the connection and SBC support.
A hierarchical approach works pretty well for data applications that are primarily client-server based and predominantly local, but not for voice and video.
The first task is always to determine in which administrative domain the problem is occurring. None of these teams will ever admit that they might be the source of the problem, so test tools are required.
By disaggregating the signaling from the transport, Stealth has opened up the possibilities for changing how we find the other guy. This kind of open environment will create rapid innovation.
Glowpoint's idea of separating the interconnect service from the application-level functions like bridging makes sense.
Business to business video requires compatibility at a series of levels, providing a new challenge for the industry.
Tandberg appears to be actively addressing the signaling components of the problem. The transport problem is not yet addressed
With so many enterprises turning to video to decrease costs and increase communications, it was time for some focused meetings on the tradeoffs.
My guess is yes, but not for awhile.
First and foremost we need network connectivity to ensure bandwidth and to create end-to-end Quality of Service (QoS).
When I pick up my telephone, I can call anyone in the world. But my enterprise video conferencing system can often only connect to video systems within the same enterprise.
What specific business problem are you trying to solve with video conferencing?
There are a number of efforts to build voice and video applications that deliver high quality results over a not-so-good network.
Multiple T1 or E1 links can be combined to provide a logical link with a higher bandwidth. But how those links are combined can affect the behavior of the network.
For a newcomer, there is a daunting array of choices, types of video conferencing, types of interconnect, design problems, integration issues and more.
Perhaps the next few years will be dominated by single-codec connections while we wait for telepresence standards to emerge.
Is there a legitimate technical reason why video should be at a lower priority class than VoIP?
Burstiness in your telepresence traffic stream is not a feature.
After committing to deploy Telepresence, one of the first decisions is: carry the video traffic on the data network or build a separate WAN network exclusive to the video streams.
If we think about all the things that can go wrong on a phone call or on a video call, the list is much longer than just the IP-network transport.
What is the difference, and what do I really need to make my voice and video conferencing behave well?
The WAN acceleration tools have a number of tricks. Will this help my voice and video? Not directly, but indirectly.
Network administrators want to be fully in control of their networks. So their preference is to decide for themselves which packet streams should get high priority, and which should be constantly relegated to the lower classes. But this doesn’t work very well for video conferencing.
The service provider community is pretty excited about Teleconferencing. But do they really know how to carry this traffic so high quality video is delivered?
This week in San Francisco I am seeing video become a substantial portion of the conversation.
I got a number of responses to my last post on the challenges that desktop video will create for the network. Iit seems like there is either significant development or marketing work left to be done.
I attended the Polycom Users Group (PUG) meeting in Orlando this week, where I was speaking about diagnosing video conferencing issues in the Enterprise network. Andrew Davis from Wainhouse Research gave an interesting presentation with his predictions for video conferencing...
Video is most often connected via E.164 dialing, or phone numbers. This phone number strategy is a legacy of when all video conferencing connections were done via ISDN, which used phone numbers to establish the connection. But now we have moved to video islands within enterprises and the E.164 number is not as relevant. Why do we want to continue to use this legacy dialing methodology for connecting our video calls?
A Session Border Controller (SBC) is a device that is specifically designed to understand the H.323 and SIP protocols and act as a security gateway to allow video (and voice) traffic in and out of the enterprise network. But the SBC has additional capabilities
There are two approaches to getting video across the corporate firewall. One uses tunneling (H.460) and the other uses a proxy or session border controller.
Implementing video conferencing inside the enterprise requires all the QoS stuff I have been talking about all year. But crossing the firewall to an Extranet or to the Internet often causes real headaches. Migraines! Why is this so difficult and...
I have been writing the last few weeks about the challenges of creating a global interconnect that will support telepresence. We looked at the networking solutions provided by IPV Gateways, Virtela Networks, and Masergy Networks. Glowpoint is another player in...
I discussed the telepresence (and video conferencing) global connectivity problem and the solutions from IPV Gateways and Virtela Networks in my last 3 posts. Today let’s look at how Masergy has structured their MPLS network and the Masergy Video Exchange...
I’m still working through the issue of how to connect multiple WAN providers to get the best global connectivity for Telepresence. I described the problem in this post, and then last week discussed one solution in this post. A few...
Connecting telepresence across the globe may require the services of more than one WAN service provider. I discussed this in detail in last week’s post, and talked about the problems that this presents. Today I want to take a look...
A majority of the enterprises I have worked with on telepresence solutions have offices distributed around the globe. To connect these far flung offices, the enterprises need a carrier who can provide the high bandwidth and high quality transport that...
The constant high-bandwidth barrage of packets created by a telepresence system can be too much for some routers and switches to handle. This can be a final-hour unwanted surprise for a telepresence deployment, so it merits some early investigation. Let’s...
Your WAN service provider is a critical component of a telepresence deployment. Much of the responsibility for delivering low packet loss, low jitter traffic to your locations around the globe lies in their hands. The instrument that allows you to...
Telepresence is an interactive real-time application, which means it is delay sensitive, loss sensitive and jitter sensitive. This sounds familiar: it is just like VoIP, with the one difference being that it has huge bandwidth requirements. VoIP is treated as...
My last blog discussed using an overlay versus using a converged network for telepresence. For either approach, the next step is to analyze the bandwidth demand of the telepresence and determine which links of the network are required to support...
The boss as asked you to deploy telepresence and your job is the network. The first decision to make is: Do we implement an overlay network or converge the telepresence traffic on the data network? An overlay network means a...
Telepresence crashed the Unified Conferencing party about 2 years ago with fabulous promises of high-quality at-a-distance conferences that make you believe you are in the same room. The quality of the HD video images, the stereo wideband sound, the carefully...