SHARE



ABOUT THE AUTHOR


John Bartlett
John Bartlett is a leading authority on real-time traffic, application performance and Quality of Service (QoS) techniques. He specializes in...
Read Full Bio >>
SHARE



John Bartlett | September 30, 2008 |

 
   

Video Tunnels Through the Firewall

Video Tunnels Through the Firewall 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.

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.

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. This issue is confused a bit by the vendors, because Tandberg pushes one approach and Polycom pushes the other. In fact a reader, Mr. Nutley, posted a comment on my last approach saying the problem is solved, H.460 is the way to go. Let's start with the H.460 tunneling and see where it makes sense to use this approach.As described in my last post, the nature of video is that we need to be able to initiate it from either side of the firewall and have it successfully cross the firewall, without compromising the security that the firewall provides to the data network. So we have to find a way of allowing this traffic to flow that still respects the concerns of the security team about hackers, who also want to cross the firewall and will take every opportunity to do so.

The H.460 solution (e.g. the Tandberg Expressway) provides a trusted server outside the firewall that acts as a proxy for all video conferencing traffic that crosses the firewall. Endpoints register with the H.460 server and open a channel to the server to send and receive signaling messages.

When an endpoint wishes to connect with another endpoint, signaling passes through the server. The server provides its own IP address as the destination IP address for all media streams. Each endpoint sets up a connection through the server, and so the firewalls on each end allow the call setup, since each was initiated from the trusted side of the firewall.

Note that the laptop user who is not behind a firewall gains access in the same way by connecting directly to the H.460 server.

The clear advantage to this approach is that there is no need to create special rules on the firewalls, and no need for the firewalls to understand the complexities of the H.323 or SIP protocols. Internal IP addresses are protected because each firewall does its usual NAT translation. The far-end video conferencing system never sees any address other than the address of the H.460 server. External endpoints gain access directly as well by registering to the same H.460 server. For a small deployment this solution works extremely well. The simplicity of the setup and call process makes this architecture the easiest way to go for small numbers of endpoints and/or small numbers of geographic locations (offices or remote sites.)

As the number of locations and the geographic diversity increases, however, this approach has some clear scaling constraints. The single server is managing not only signaling but all transport streams. As the number of simultaneous calls grows, so will the demand on this server, and it will soon run out of capacity.

The second problem is one of geography. When offices become globally located, having a single server may mean that calls get routed very long distances. Distance translates into latency, which degrades the interactivity of the call.

For instance, suppose in the diagram above that corporate HQ and the H.460 server are located in Chicago. Suppose further that one of the offices is in Singapore and the remote worker is in Hong Kong. When these two endpoints connect for a video call, the call is routed from Singapore to Chicago and then back to Hong Kong. Clearly a more direct route would be preferable for the global enterprise.

In my next post we will look at a different approach which is not quite as simple as H.460 but does a better job of addressing the scaling and geography issues.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.





COMMENTS




April 25, 2018

Yesterdays simple phone call to a contact center or business location is rapidly becoming todays interactive session, spanning multiple channels and devices. If you need to know how Omnichannel can

March 7, 2018

Video collaboration is experiencing significant change and innovation-how can your enterprise take advantage? In this webinar, leading industry analyst Ira Weinstein will present detailed analysis

February 21, 2018

Business agility has become the strongest driver for enterprises to begin migrating their communications to the cloud-and its a benefit that enterprises are already realizing. To gain this benefit

March 12, 2018
An effective E-911 implementation doesn't just happen; it takes a solid strategy. Tune in for tips from IT expert Irwin Lazar, of Nemertes Research.
March 9, 2018
IT consultant Steve Leaden lays out the whys and how-tos of getting the green light for your convergence strategy.
March 7, 2018
In advance of his speech tech tutorial at EC18, communications analyst Jon Arnold explores what voice means in a post-PBX world.
February 28, 2018
Voice engagement isn't about a simple phone call any longer, but rather a conversational experience that crosses from one channel to the next, as Daniel Hong, a VP and research director with Forrester....
February 16, 2018
What trends and technologies should you be up on for your contact center? Sheila McGee-Smith, Contact Center & Customer Experience track chair for Enterprise Connect 2018, gives us the lowdown.
February 9, 2018
Melanie Turek, VP of connected work research at Frost & Sullivan, walks us through key components -- and sticking points -- of customer-oriented digital transformation projects.
February 2, 2018
UC consultant Marty Parker has crunched lots of numbers evaluating UC options; tune in for what he's learned and tips for your own analysis.
January 26, 2018
Don't miss out on the fun! Organizer Alan Quayle shares details of his pre-Enterprise Connect hackathon, TADHack-mini '18, showcasing programmable communications.
December 20, 2017
Kevin Kieller, partner with enableUC, provides advice on how to move forward with your Skype for Business and Teams deployments.
December 20, 2017
Zeus Kerravala, principal analyst with ZK Research, shares his perspective on artificial intelligence and the future of team collaboration.
December 20, 2017
Delanda Coleman, Microsoft senior marketing manager, explains the Teams vision and shares use case examples.
November 30, 2017
With a ruling on the FCC's proposed order to dismantle the Open Internet Order expected this month, communications technology attorney Martha Buyer walks us through what's at stake.
October 23, 2017
Wondering which Office 365 collaboration tool to use when? Get quick pointers from CBT Nuggets instructor Simona Millham.
September 22, 2017
In this podcast, we explore the future of work with Robert Brown, AVP of the Cognizant Center for the Future of Work, who helps us answer the question, "What do we do when machines do everything?"
September 8, 2017
Greg Collins, a technology analyst and strategist with Exact Ventures, delivers a status report on 5G implementation plans and tells enterprises why they shouldn't wait to move ahead on potential use ....
August 25, 2017
Find out what business considerations are driving the SIP trunking market today, and learn a bit about how satisfied enterprises are with their providers. We talk with John Malone, president of The Ea....
August 16, 2017
World Vision U.S. is finding lots of goodness in RingCentral's cloud communications service, but as Randy Boyd, infrastructure architect at the global humanitarian nonprofit, tells us, he and his team....
August 11, 2017
Alicia Gee, director of unified communications at Sutter Physician Services, oversees the technical team supporting a 1,000-agent contact center running on Genesys PureConnect. She catches us up on th....
August 4, 2017
Andrew Prokop, communications evangelist with Arrow Systems Integration, has lately been working on integrating enterprise communications into Internet of Things ecosystems. He shares examples and off....
July 27, 2017
Industry watcher Elka Popova, a Frost & Sullivan program director, shares her perspective on this acquisition, discussing Mitel's market positioning, why the move makes sense, and more.
July 14, 2017
Lantre Barr, founder and CEO of Blacc Spot Media, urges any enterprise that's been on the fence about integrating real-time communications into business workflows to jump off and get started. Tune and....
June 28, 2017
Communications expert Tsahi Levent-Levi, author of the popular BlogGeek.me blog, keeps a running tally and comprehensive overview of communications platform-as-a-service offerings in his "Choosing a W....
June 9, 2017
If you think telecom expense management applies to nothing more than business phone lines, think again. Hyoun Park, founder and principal investigator with technology advisory Amalgam Insights, tells ....
June 2, 2017
Enterprises strategizing on mobility today, including for internal collaboration, don't have the luxury of learning as they go. Tony Rizzo, enterprise mobility specialist with Blue Hill Research, expl....
May 24, 2017
Mark Winther, head of IDC's global telecom consulting practice, gives us his take on how CPaaS providers evolve beyond the basic building blocks and address maturing enterprise needs.
May 18, 2017
Diane Myers, senior research director at IHS Markit, walks us through her 2017 UC-as-a-service report... and shares what might be to come in 2018.
April 28, 2017
Change isn't easy, but it is necessary. Tune in for advice and perspective from Zeus Kerravala, co-author of a "Digital Transformation for Dummies" special edition.
April 20, 2017
Robin Gareiss, president of Nemertes Research, shares insight gleaned from the firm's 12th annual UCC Total Cost of Operations study.
March 23, 2017
Tim Banting, of Current Analysis, gives us a peek into what the next three years will bring in advance of his Enterprise Connect session exploring the question: Will there be a new model for enterpris....
March 15, 2017
Andrew Prokop, communications evangelist with Arrow Systems Integration, discusses the evolving role of the all-important session border controller.
March 9, 2017
Organizer Alan Quayle gives us the lowdown on programmable communications and all you need to know about participating in this pre-Enterprise Connect hackathon.
March 3, 2017
From protecting against new vulnerabilities to keeping security assessments up to date, security consultant Mark Collier shares tips on how best to protect your UC systems.
February 24, 2017
UC analyst Blair Pleasant sorts through the myriad cloud architectural models underlying UCaaS and CCaaS offerings, and explains why knowing the differences matter.
February 17, 2017
From the most basics of basics to the hidden gotchas, UC consultant Melissa Swartz helps demystify the complex world of SIP trunking.
February 7, 2017
UC&C consultant Kevin Kieller, a partner at enableUC, shares pointers for making the right architectural choices for your Skype for Business deployment.
February 1, 2017
Elka Popova, a Frost & Sullivan program director, shares a status report on the UCaaS market today and offers her perspective on what large enterprises need before committing to UC in the cloud.
January 26, 2017
Andrew Davis, co-founder of Wainhouse Research and chair of the Video track at Enterprise Connect 2017, sorts through the myriad cloud video service options and shares how to tell if your choice is en....
January 23, 2017
Sheila McGee-Smith, Contact Center/Customer Experience track chair for Enterprise Connect 2017, tells us what we need to know about the role cloud software is playing in contact centers today.