Mesh Without Wires

April 26, 2010

When Wireless Video Mesh is Not ‘True’ Mesh (But Better)

Filed under: Physical Security,Public Safety Wireless — kseniacoffman @ 11:03 am
Tags: , ,

The title is a play on words, but it simply means that a ‘fully-meshed’ network design may not fit the topology or the customer requirements. But the unique capabilities of Firetide‘s mesh allow the network to meet the project performance expectations.

This post follows the theme of wireless mesh network design. (For a broader discussion, see: Network Design Considerations for Wireless Video Surveillance). To illustrate and expand on why flexibility of mesh topology is important for video surveillance, consider this: mesh is a superset of point-to-point and point-to-multipoint systems. In addition, the distributed intelligence of the mesh and transparent switching/routing within it enable performance that other systems cannot achieve. Two examples below:

Nested point-to-point mesh design

Firetide nested PtP mesh design

Firetide nested PtP mesh design (Click on image for full-size view)

Even though the design uses point-to-point and point-to-multipoint approach, many of the links are ‘nested’ (with some nodes acting as repeaters), which is only possible with mesh gear. You could deploy point-to-point (maybe) but you’d have to deploy a base station at each nesting locations, which is expensive, and also take a hit in performance as you are switching from subscriber units to base stations. Instead, the ‘nesting’ nodes are dual-radio, so they are able to communicate in both directions without throughput degradation.

Also note frequency re-use as indicated by green lines, showing the same frequency being used. This is possible since mesh in street level, and therefore the signals on the same frequency are isolated from each other and are non-interfering.

The two physical meshes you see on the image are logically a single mesh (illustrating our concept of a distributed wireless Ethernet switch), and as such, have a single IP address for the entire mesh. The two head nodes on the main building are interconnected via in-building LAN network.

What you are seeing is a real-life example of a high-performance mesh. This nested design was the best option given the site’s topology.

Linear loop mesh design

Firetide linear loop mesh design (Click on image for larger view)

Firetide linear loop mesh design (Click on image for larger view)

This is an example of a redundant linear mesh, with redundancy achieved through the completion of the circle. If one of the links is broken, the mesh will automatically re-route the traffic without any dropped packets or added latency.

The advantages of using mesh equipment vs a collection of point-to-point links in this situation are:

  • All of the links can be  system can be managed through the same network management interface
  • You get system-wide diagnostics and alerts
  • Less real estate and power required at each location (one radio node, instead of two separate boxes)
  • Latency and jitter is minimized with intra-radio switching

For more posts on wireless network design for high-performance applications, see:

By: Ksenia Coffman – Connect with me on Twitter or LinkedIn.

April 25, 2010

Practical Social Measurement for B2B: #B2Bchat Recap

Filed under: B2B,Corporate Twitter,Social Media — kseniacoffman @ 8:05 am

#B2BChat Thursday 8 PM(This post originally appeared on B2Bbloggers.com web site. For all posts on #B2Bchat, search for #b2bchat tag on B2Bbloggers, or visit http://www.b2bbloggers.com/blog/tag/b2bchat/).

B2B companies, especially those that are not web-based businesses, tend to be late adopters of social media. This has been my personal experience, as Firetide’s social media efforts started less than a year ago (although I had participated in LinkedIn groups for longer than that).

Many companies only have perfunctory efforts – they have twitter accounts, for example, but update infrequently or don’t engage with their followers. Given that we are early adopters (funny to say that given that social media been the rage for years, it seems) we still have to justify the time and effort allocated to social media efforts.

So the Social Media Measurement #B2Bchat was in part exchange of tips and insights, and in part a venting session – which everyone needs every now and then.

Some highlights from the session.

As a B2B marketer, how do you justify time spent on social media? Are there any detractors within your organization?

I was surprised to hear from one participant that “Day of having to justify SM to anyone is over.” This has not been my experience. I suspect that in many B2B companies social media is still flying under the radar, and needs to “come out of the shadows.” So there will still be adjustments as social media gets fully integrated into marketing plans, and stops being a skunk works project. Many comments confirmed my impression:

  • I just make the time for it. There are a few detractors in my company, but most support our SM efforts.
  • Some are quick to be detractors: tend to be expecting too much, or not taking time to understand.
  • I view SM as an extension of ‘traditional’ communications – advertizing/PR, so weaving it into our regular mark. programs
  • I have spoken to some, who do see fear of unknown and lack on control to be concern.
  • B2B is all about relationship building during long sales cycle. Social media is a great way to build relationships.
  • I can link revenue directly back to my social media contacts/time. Dramatic increase year to year.

What are social media’s practical benefits, even for companies who do not monetize their web sites?

The responses varied from lead conversion metrics (from those lucky enough to have a closed-loop lead tracking system), to better understanding he industry landscape and listening to conversations, market intelligence and building personas.

  • SM gives the users a chance to interact with you as a business/product. It’s a big plus.
  • Looking at SM as extension of PR, I track mentions, engagement, as well as briefings & other PR opps secured through SM
  • Maintaining/monitoring brand perception in real time is an advantage, awareness of enthusiasts/critics comments = opportunity
  • A step above brand monitoring is establishing credibility as an industry expert.
  • Competitive/market intelligence is a huge advantage that SM brings; gets rid of ‘tunnel vision’
  • SM for a small biz helps to level the playing field; leads to interaction with industry pros – as long as you provide quality content

The last observation was especially interesting to me; you don’t need to have a huge PR or ad budget to know what is happening in the industry, and you can engage with the influencers directly. In addition, having the first-mover advantage, you can establish a position in social media and stand apart from the crowd.

Do you know the impact social media activities have on your brand awareness?

There was no easy answer to this question yet, so many of us have to rely on qualitative feedback.

  • You do if you set GSOT (goals, strategies, objectives & tactics) at start & keep scorecard two track progress.
  • Awareness is a measure of total reach and increase in reach online. So yes through analytics that can be determined
  • Brand awareness can be measured and tracked to some extent; but crucial to establish a baseline from which to measure
  • It can be difficult to measure, particularly for small businesses without resources and access to high powered apps or 3rd party software
  • Social Media ROI question is tough. BUT, what’s the ROI of having a telephone? Or email?
  • Without question, SM lets small companies and startups compete with vastly larger firms.

Do you generate leads with social media? If yes, how do you track them?

  • We track leads from SM by using Google Analytics and unique URLs.
  • We do a lot of content registration: Webinars + white papers through Facebook & Twitter. 5-10% of registrations come from SM.
  • SM for our company has been key for building awareness. Our web analytics show SM as top referrer.
  • We assign a unique URL to each tweet and then track inbound clicks all the way to a lead or other success event.

What are the tools that even companies without social media budgets can use to track impact of their social media presence?

  • Trackur; Google Alerts; even Tweetdeck are great measurement tools (or combination thereof)
  • For tracking twitter engagement over time: @twitalyzer & @klout
  • PostRank is a great way to tie social media with blog performance.
  • Great SM measurement tools being mentioned: PostRank, Twitalyzer, Klout, Rowfeeder, Trackur, Radian6 (although a later commenter said “Radian6 is a great sm product, but I don’t have $’s for it.”)
  • If you are using an existing web analytics package, you can use APIs like the Twitter search/REST API to grab data on buzz.

What are the objections you encounter regarding social media initiatives? Any tips for overcoming them?

This was more of a venting session as I mentioned early. It surely felt good!

  • Biggest obstacle I hear about is security and inertia
  • The age old challenge in B2B = tying SM to revenue. Yes, it’s a cliché at this point.
  • Do I have the resources in time, $ & people to make it work? It is a relevant concern.
  • Ah, the famous question: ‘What if they say something bad about us?’ Answer: ‘Then you have a prime opportunity for conversion.’
  • Internal objections when starting SM initiatives? “Our clients don’t use SM.” “It’s a time trap.”
  • I have a client that would love to tweet if they could do so to a controlled audience. [Classic!]
  • “We don’t have time to do SM right.” “Our B2B customers aren’t using SM.” “CEO won’t like negative feedback.”
  • Another challenge is the perception that social media is cheap and does not require any specific knowledge and expertise.

So, even as it may seem that social media is a given, many B2B companies are still in the early adoption phase, and are grappling with associated challenges. The dialog helped bring them to light.

As one of the participants said: “Social media is an amplification of the conversations that are happening anyway.” With social media you have the opportunity to participate, rather than staying on the sidelines. Jump right in!

For other posts on social media topics, see:

April 15, 2010

LA County Sheriff’s Wireless Surveillance: Video Interview with SDN

The interview below was pure luck. I knew that Leischen Stelter of Security Director News was looking to interview end users at the ISC West show, but I had not heard of anyone coming. 2010 was an especially tough year for end-user trade show attendance, so I got lucky that the Los Angeles County Sheriff’s Department (LASD) team stopped by our booth while I was there. When I asked if they’d be willing to do a video with SDN, they responded that they had to email up the chain of command. The permission was granted, SDN had a slot available for a video interview – and we were in business.

See the video at Security Director’s News: Los Angeles continues to deploy wireless mesh

Some interesting quotes:

“The success of the system has been infectious: other cities have seen it; other areas have benefited from it. This is a living project and will continue to grow.

“The great thing with wireless, we are not limited by location: we can expand and grow as we see fit, where the needs are in terms of controlling crime and protecting the citizens.

“Our key requirement has always been evidentiary-grade video. For us, this is 30 frames per second 4CIF: high-quality video that would stand up in court. If this requirements could not have been met, we felt that the video system would be inadequate or could only provide basic needs, such as scene assessment.

“Having a proven wireless system that’s capable of providing high-quality video has been essential to us when it comes time for prosecution.

“Believe it or not, it’s amazingly simple with the wireless system we are using for these deployment, which is Firetide’s [wireless mesh network]. Install [the nodes], line up, turn on the power, put the cameras up, minor fine-tuning, and you are good to go. It’s very simple.”

Again, the issue of whether wireless video surveillance is simple comes up. (See my earlier post: Is Wireless Video Surveillance ‘Easy‘?) Note that the comment is from an end-user; they do not design the network nor configure the nodes. They have an excellent integrator – Leverage Information Systems – who does that for them. So from then end-user perspective, the deployments are “amazingly simple.”

As an aside, when the first SDN’s video with LA County Sheriff’s Department was released after ASIS, I was asked: how come you keep promoting the deployment, it’s only 30 cameras. Yes, at that time it was 30 cameras, but for any small to medium size municipality, this is a decent size project, so the interview can provide interesting reference points. Besides, even the largest projects start with a Phase One.

Besides, consider these facts:

  • LASD has a policy that does not prevent its representatives from talking to the media (policies vary greatly by municipality or agency, some do not allow any comments at all)
  • They can secure approval for a media interview within days (as was the case with the interview at ASIS), and even within hours (for ISC West interview)
  • Last but not least, they attend trade shows.

By the way, the first SDN interview with LASD is their most popular video of all times with 5,500 views. The second interview is already SDN’s 6th most popular video of all times. I don’t know how or why these videos get so popular; “cops with cameras” must be a compelling topic.

For additional information on the LA County Sheriff’s Department project, see:

April 13, 2010

Network Design Considerations for Wireless Video Surveillance

My post Why Flexibility of Mesh Topology is Important for Video Surveillance drew an extended comment from Joe Wargo of AO Wireless, and I’m using it as a jumping off point to address some of the issues impacting network design for wireless security and surveillance. (Sections in italics are Joe’s comments, with my commentary below each paragraph. Headings are mine.)

PtP, PtMP and mesh all play a role in wireless video surveillance

“As an outdoor wireless integrator that specializes in video backhaul solutions, I would like to comment on this conversation. Wireless mesh products do have a great fit in large video deployments. As well does point to multipoint and point to point backhauls. Each has their fit and their limitations. In a deployment that covers a large geographic area (e.g. a city wide deployment) the best design will more than likely utilize all three topologies. Obviously one of the key requirements of video backhaul is bandwidth and latency. Consideration for what type of video the end user is trying to capture is also an important factor.”

Agree completely: one topology cannot address all of the needs of a deployment. Further, Firetide’s mesh for large scale deployments is never a single ‘monster’ mesh; that would be impractical from network management and bandwidth/latency standpoint.

multimesh network view

Multimesh: network view as shown via Firetide's NMS (with Mobility Controller)

The best practice for video security network design is multi-mesh, interconnected by wired or wireless backhaul. Fiber often plays a role as a backhaul, when fiber is available and accessible. To illustrate my point on how these networks are built out, here are a few examples citing Firetide deployments.

  • Dallas PD project is a multi-mesh design with point-to-point wireless backhaul, utilizing mesh for street-level connectivity, and BridgeWave wireless links for backhaul. Dallas PD wanted a network independent from any other city infrastructure (not sure if it was not available or could not provide enough capacity), therefore they opted for a 100% wireless solution.
  • Chicago OEMC video install is a multi-mesh design with fiber backhaul. The city already had a lot of fiber installed, so wireless mesh fills in the ‘fiber gaps.’
  • Los Angeles County Sheriff’s Department is expanding their wireless video security network using Firetide MIMO mesh nodes in point-to-point configuration (dual-radio bonded) as an alternative to dedicated point-to-point backhaul. Los Angeles lacks the extensive fiber infrastructure of Chicago, hence the decision to utilize 100% wireless connections.

Requirements for video quality depend on situation

“Too often we see deployments that are not optimized because the end user doesn’t truly understand the fundamentals of video surveillance and their networking requirements. For example, often a end user will say they need 30fps for both viewing and recording. From a video perspective this is not best practices. There is very little difference that the human eye can capture from 15fps from 30fps. Recording should be what is needed (e.g record on event or a few fps). It does depend on the requirement of course.”

Our public safety deployments can be anywhere from 12 fps to 30 fps, most often with the same stream being used for recording and viewing. In one of our deployments, where the customer did have a requirement for separate viewing vs recording, the recording is done at 30 fps and viewing is at 7 fps. Law enforcement agencies often city ‘evidence-grade’ video requirements for forensic investigations and prosecutions, when they specify 30 fps/4CIF. This is indeed best for areas with fast motion such as intersections. But in most case 15-20 fps works just as well.

Ironic but true: wireless mesh is sometimes not ‘true mesh’

“Too often the end user is putting more video over the network than should be required. Bandwidth and latency becomes an issue. Second issue is that most do little or very poor RF planning. Too often we see installations that people are using the wrong technology in the wrong situation. Wireless mesh devices help with getting around obstacles. Too often through we see mesh not really meshing at all, but used as repeaters in a chain fashion. A great advantage of many mesh devices is they have that flexibility. Problem is that they are not utilizing their full functionality. There aren’t many applications that require “true mesh” capabilities in a fixed camera environment. But they work well with bringing multiple cameras together. Problem though becomes latency if too many nodes are used before a backhaul (using PtMP or PtP).”

True, the ability of mesh to repeat the signal is one of the key advantages of this type of topology. And indeed, even though we say ‘mesh’ to describe what we do, the actual deployment topologies in the field vary greatly, even when using 100% Firetide gear. Most often the end result is a ‘partial mesh’: some redundant links, some PtP and PtMP, and some ‘linear mesh’ (mesh nodes strung together to reach into a neighborhoods or go alongside a key thoroughfare; mostly when the budget does not allow for 100% coverage of a given area).

The flexibility of mesh allows to easily add additional nodes and fill in the mesh gaps in the next phases of the deployment. We’ve even deployed Firetide in circulate mesh – 5 remote facilities linked in a daisy chain by mesh nodes. As an aside, even with a linear mesh you can build in redundancy: if you have a gateway node at each end of the daisy chain, if something should happen to an intermediary node, the traffic will be automatically rerouted to the ‘backup’ gateway node, without an interruption in a video stream. But the system needs to be designed with that in mind.

“Wi-Fi mesh” and “infrastructure mesh” are vastly different

“Newer 802.11n (Atheros) based chip sets are providing more throughput but also require more spectrum and are more susceptible to interference in the unlicensed bands . The worst thing possible is deploying a lot of devices on omni-directional antennas in a small geographic area. Mesh radio in fixed installations should use directional antennas and controlled RF. I understand that manufactures market the full capabilities of their radios, but too often over market the true field performance in a real world environment.”

Could not agree more on the antenna choices. Firetide is not “Wi-Fi mesh” as defined by other vendors (of the past and even today – see The Many Interpretations of ‘Wireless Mesh’): for them, mesh is omni-directional, radiating signal in each and every direction and hence it has “a problem with video.” Omni-directional antennas have advantages for mobility applications – the antennas should be omni-directional, so that the mobile mesh node can pick up the best available signal. you can use omni-directional antennas in fixed deployments – if and when mesh nodes are at the same elevation and the RF environment is relatively clean. See what happens when an integrator tries to use omnis for video outside of these ideal parameters.

We consider mesh APs to be “Wi-Fi mesh”: devices with omni-directional antennas, often with an AP built in for client access; these devices were designed with low-bandwidth data in mind. We call what Firetide does “infrastructure mesh”: dual-radio IP infrastructure designed from the ground up for real-time high-bandwidth applications: voice, video and data. Hence trying to fit mesh APs in a video surveillance space (which they were not built for) is often a recipe for disaster, or requires many more mesh nodes in a given area, expensive wireless or wired backhaul and more complex network design and management.

RF and IP knowledge key to successful wireless video surveillance deployments

We have been extremely successful deploying video backhaul applications using PtMP, PtMP and Mesh together, etc. The one thing that should be stated with mesh is that after a few nodes there should be a backhaul in order to control latency. Last thing to note is that not all video cameras work the same over wireless. We have done a lot of testing with various cameras and over various wireless radio systems. Research should be done by the buyer prior to choosing the right camera with the right wireless systems. And as always, always, always, consult an RF professional to design and install the network correctly.

Agree with the part that all of the topologies are important for video. But do not 100% agree that backhaul is needed for every few mesh nodes – it depends on a particular vendor, or rather the technology they use (and definitely does not apply to Firetide’s mesh). What you said is true for single radio mesh nodes, as the throughput is reduced by 50% with each hop, because the mesh has to both receive and send on this single radio. The limitation of ‘backhaul for every few nodes’ also applies to mesh APs because of the introduced latency, jitter and best-effort QoS inherent to standards-based Wi-Fi access points.

Seoul Cheonggyecheon

Linear mesh topology at Cheonggye waterway

With Firetide’s dual-radio mesh nodes and proprietary routing protocol that runs within the mesh, the multi-hop has limited impact on performance, both in terms of capacity and latency. We have many deployments with multiple hops, such as Seoul’s Cheonggye Waterway project, with 10 hops each in two directions from a central point. (And that was done with our previous generation of product using 802.11a/b/g radios, with 1.5 ms of latency per hop. Our new MIMO product line reduced latency even further – to .9 ms per hop. So even with 10 hops you are still only at 9 ms aggregate latency, and able to maintain 80-90% of the original throughput.

We can recommend IP cameras that we know to work well over Firetide’s wireless infrastructure, two prime examples being our official solution partners Axis Communications and Sony Electronics, and many others. We’ve also been deployed with analog cameras, connected to the IP network via encoders – and have numerous deployments with this setup (people still like analog cameras). Theoretically, any IP camera or IP encoder should work as Firetide is purely an IP transport. However, some camera vendor’s implementation of IP may introduce certain quirks that you should know about before making a selection.

On the last point – agree completely: mesh, or any wireless, is specialized expertise, and requires both IP networking and RF knowledge. The biggest issue we are seeing with deployments coming in into our tech support is the lack of professional site survey done prior to deployment, and hence RF network design issues. Plug: Firetide provides professional services, including on-site engineering site surveys, to our channel through a network of vetted professional services partners. These services are transparent to the end-user; they do not need to know who’s performing the work, as long as the integrator is billing the customer, so the channel is protected. With professional services, even integrators who are new to wireless can have successful deployments, while learning on the job. It does not take rocket scientists to successfully deploy these systems, but you need to know what you are doing.

For additional discussion on the topic of wireless mesh for video surveillance, see:

By: Ksenia Coffman – Connect with me on Twitter or LinkedIn.

April 9, 2010

Notes from Anixter Integrated Physical Security Seminar

It’s always interesting to get out of the office and mingle with integrators, consultants, vendors and distributors. I had the opportunity to do just that at Anixter’s Integrated Physical Security Seminar on Thurs April 8 in Denver.

First off, the event was very well attended for a road show – the final numbers are due from Anixter, but there are telling me there were 100+ attendees, not counting vendors and Anixter personnel. A lot of people seemed new to IP though (consider comments from a security specialist in a big bank, who is still dealing with VCRs). We’ll see what the final tally/feedback is.

IP fundamentals still needed for reseller channel

Ed Wassall of Anixter delivered an excellent intro presentation on IP networking, with forays into Layer 2 switching and Layer 3 routing concepts. That was a reminder that yes, you can have all sorts of technology and devices on the edge, but your core infrastructure is what you have to get up to par, if you want to have a successful security system. It was also a nice tie-in with Firetide’s message on our wireless infrastructure approach, with L2 distributed wireless Ethernet switching with L3 routing protocol within the mesh, as opposed to “Wi-Fi mesh” on one side, and point-to-point or point-to-multipoint systems on the other .

Integrated security solution for university campus

Denver PD focuses cameras on crime

Denver HALO security camera

The IP fundamentals were a great intro into the sessions on cabling by Anixter, wireless infrastructure by Firetide, video management and PSIM (physical security information management) by OnSSI, video technology by Axis Communications and integrated access control by S2 Security. We all had to present solutions for a hypothetical large university campus, which played to Firetide’s strengths in outdoor security and “wireless-enabled campus”: using wireless infrastructure mesh as outdoor backbone for video security and surveillance, mass notification devices, outdoor/indoor Wi-Fi access, LAN extension, VoIP as well as temporary and portable installations.

I, of course, also brought up Denver’s HALO (High Activity Location Observation) project, which utilizes Firetide for mesh connectivity. See picture at left – the white boxes are “Firetide inside” (i.e. contain Firetide indoor mesh nodes); also see our announcement around the DNC and coverage in Denver Post.

Road shows can deliver useful content

Anixter always puts on a great (road) show; they are able to get people in. Considering my concern on whether roadshows are just glorified sales pitches, I posed a question over lunch to one of the attendees (a telecom consultant getting into IP security and surveillance): “Has the content been commercial in nature, or was it educational?” He said – without hesitation – that the content was useful and very light on commercial messages. Indeed, Anixter had gotten better in policing vendor’s content and cutting out pages of product specs.

Former rep shares feedback

I ran into someone who used to be a Firetide’s manufacturer’s rep, and then went on to do other things in the security market. It was interesting to trade observations on physical security and wireless markets, and to talk to someone who was quite familiar with us, but no longer ‘vested’ in Firetide so I could get honest opinions. Among other things, we talked about our recently announced wireless Ethernet bridge, and he said: “It’s been long overdue!” So I hope it bodes well for the new product. I also asked him what the biggest challenge that Firetide faced was – but you’ll have to email me for his answer (kcoffman-at-firetide-dot-com).

Redundancy crucial for mission-critical communications

Another interesting conversation was with a public safety department in an adjacent municipality. They are looking to deploy wireless infrastructure, in addition to the fiber connecting their facilities. When I heard they had fiber, I inquired why they needed wireless on top of that. The answer was that they didn’t control the fiber network, there were outages, and that they needed redundant infrastructure. That is why they were interested in mesh – even though they were being pitched by a point-to-point wireless vendor. When they gave me their top budget estimate per facility, I thought: “Wow, for that kind of money you can deploy Firetide’s mesh & then stream video over it” – even though the requirement for now is just data. Of course, the estimate may be a pie in the sky, but if mesh is not possible budget-wise, then we have a low-cost point-to-point solution that they may want to look into.

In summary, the value of in-person events as opposed to online events is that you get to meet people in the industry. Hats off to Anixter for a great networking opportunity.

What have your experiences with vendor road shows been?

Image via Denver Post.

By: Ksenia Coffman – Connect with me on Twitter or LinkedIn.

April 6, 2010

To Mesh or Not To Mesh for Wireless Security and Surveillance

Or Limitations of Point-to-point and Point-to-multipoint Systems for Real-time Video

This is continuation of the discussion on “Why wireless mesh” that got started when I tweeted out my article for SMD last week: Wireless Mesh for Video Surveillance: Why and How. We do get these comments: wireless mesh is expensive, why wouldn’t you use a much simpler and cheaper point-to-point links for video surveillance? Our competitors in the point-to-multipoint space, including fixed WiMAX or ‘WiMAX-like’ systems, echo that by saying that mesh is very complex, multi-hop creates ‘unpredictable environment,’ while point-to-multipoint is deterministic, and therefore better for video.

Disclaimer, before I get underway: low-cost Wi-Fi based point-to-point links have their time and place in video surveillance. If you need to connect a couple of outlying cameras across your parking lot, you can successfully use point-to-point links. We have our own point-to-point product line for exactly these scenarios. However, for the purpose of this article, I’ll focus on deployments with 15 camera locations or greater – a campus, downtown, or industrial site type of environment. The number 15 is somewhat arbitrary, but this is approximately when a lot of wireless providers start having challenges supporting real-time high-resolution video.

PtP and PtMP networks quickly run out of usable spectrum

Compared to point-to-point and point-to-multipoint systems, mesh differentiator is and always has been the ability to “repeat” the signal, and therefore extend the reach of the network beyond the first hop. Eventually PtP and PtMP wireless systems run out of usable spectrum: in order to achieve a clear line-of-site (required at 2.4/4.9/5 GHz), they are forced to radiate from at least one high point (tower or tall building). This fills the airwaves with a chosen band of frequencies, which are limited in number.

Mesh avoids this issue by being able to isolate the RF signal. Radios are typically mounted on street poles where the RF can be directed between buildings and trees in a given pathway back to a final destination, through a series of repeater nodes in a multi-hop configuration. Because the frequencies can be reused along the path, the same limitations of PtP and PtMP solutions do not apply. However, Firetide is the only mesh product that also maintains the low latency, high capacity and distributed architecture required for real-time video, which is why we excel in this space.

Transition to MIMO creates more challenges for PtP and PtMP

It’s also important to note that as the wireless manufacturers move from 802.11a/b/g to 802.11n-based systems, channel size increases from 20 MHz to 40 MHz. That equates to 2 channels in the 2.4GHz range, 1 channel in the 4.9 GHz range, and 11 channels in the 5 GHz range. In other words, 802.11n cuts down the available number of channels by half which will limit the scalability of P2P and P2MP systems even more.

Rigid architecture of PtP and PtMP not the best at handling challenging environments

Urban Canyons Challenging for PtP & PtMP

Urban Canyons Challenging for PtP & PtMP

RF considerations aside, PtP and PtMP system also face other challenges. As I already mentioned, PtP and PtMP systems require tall assets to place the base station in every sector of coverage. We’ve won deals over these providers just because these tall assets (rooftops of privately owned buildings) could not be secured in sufficient quantities. The same challenge applies to industrial facilities, where deploying mesh can be the alternative to constructing towers.

In dense urban environments, even if you do get access to rooftops, the topology of “urban canyons” is such that you cannot achieve LOS from the rooftops to all the camera locations, which requires you to go street level. So that takes us back to street-level coverage with multi-hop, which can only be delivered by a mesh topology. In one city-center deployment – because of dense foliage – we had to shoot under the tree canopy; no point-to-multipoint system can do that.

Of course, you could string point-to-point links and achieve the same mesh-like topology, but then you’ll run into issues of latency and jitter, as you are switching between one PtP link to another. This is most evident in bandwidth intensive applications, such as video, which is why products like Ubiquity or Tranzeo, along with other Wi-Fi products out there, will never be good for more than a handful of cameras in a given geography. The cost advantage is also reduced: you need 4 PtP radios for two links, vs 3 mesh nodes for the same 2 connections. So no dice with PtP either.

Capacity limitations in PtMP lead to high costs of deployments

There are virtually no capacity limitations in PtP space; you can get up to 1 Gig links, from providers such as BridgeWave. So I’ll address the capacity limitations of PtMP systems that we compete with for video surveillance deployments. WiMAX, which is being touted by WiMAX providers as the solution for real-time video surveillance, today delivers only about 30 Mbps of capacity per base station, divided by the number of subscribers. (Theoretical data rate for a fixed WiMAX system is 70 Mbps, so real-world 30 Mbps is generous). A typical standard resolution video camera outputs a 2-3 Mbps video stream, a 1080p HD cameras requires 5-7 Mbps of bandwidth (using H.264), and a 12 megapixel camera can hit as high as 30 Mbps. So you do the math.

According to IMS Research, by 2013 revenue from HD and megapixel cameras will equal that from standard definition cameras (see Day 1 ISC West 2010 Impressions). These systems will be challenged even more as user adoption of HD and megapixel grows.

Mesh is expensive, but vastly less so compared to fiber

To the final argument: “mesh is expensive.” Our solution is not cheap, especially compared to low-cost PtP. But for these types of deployments that I was talking about, low-cost PtP is not the true competitor. The alternative (or the starting point) in the customer’s mind is often fiber – and fiber is vastly more expensive than any type of wireless. In fact, 90% saving off fiber infrastructure is the number I heard just recently at ISC West from our integrator who priced out fiber vs Firetide’s MIMO mesh infrastructure.

In summary, yes, point-to-point links are sufficient for small scale deployments, and you may not need mesh in this case. However, as you move beyond a few links, multiple point-to-point links become very complex to manage, and you’ll ‘gain’ in network management headaches and poor performance what you saved on cost.

For additional discussion on the topic of wireless mesh for video surveillance, see:

Image via Flikr

By: Ksenia Coffman – Connect with me on Twitter or LinkedIn.

April 2, 2010

Why Flexibility of Mesh Topology is Important for Video Surveillance

Setting aside the opinions on contributed content, which is itself an interesting discussion, I’d like to address comments from John Honovich on the article I wrote for SDM magazine: Wireless Mesh for Video Surveillance: Why and How.

Quoting from the article: “The flexibility of mesh allows it to be deployed in … point-to-point for backhaul, ptmpt, or “true” mesh for complete redundancy,” John commented: “Totally misleading — why would you use mesh in most ptp scenarios? It’s far more expensive. But SDM lets @firetide run this as a primer on why and how, misleading their readers for Firetide’s benefit.”

To address John’s concern, and clarify for others who may have followed the Twitter discussion:

Mesh and point-to-point topology

Mesh and Point-to-point

In the physical security world, mesh has come to be perceived as a viable transport for large-scale video surveillance deployments, hence the focus of the article, as requested by the publication. Further, I was not advocating use of mesh for any and all point-to-point deployments, just stating that it can be deployed in point-to-point configuration.

The article was not comparing mesh with low-cost, low-capacity gear, such as point-to-point wireless Ethernet bridges, that John seems to be alluding to as more cost effective. (Plug: in fact, we now have our own point-to-point solution to address scenarios where customers need to connect one or two outlying cameras that we just announced at ISC West). To John’s point, using most vendors’ mesh for such deployments would be an overkill and quite expensive: multiple thousands of dollars per link.

Where customers do see the value in the flexibility of mesh is the ability to use the same set of equipment for both mesh coverage (i.e. street level connectivity) and the point-to-point backhaul – to send the aggregated traffic to the command center for viewing and storage, or to interconnect multiple meshes, each with numerous cameras.

The primary advantages are:

  • End-to-end network management – there are fewer ‘moving parts’ in the deployment, and you don’t have to worry about interoperability between different sets of equipment (one for camera connectivity and one for backhaul)
  • Significant cost savings compared to dedicated point-to-point backhaul, which can be very expensive ($15,000 per link is not unheard of). Specifically, our customers have said that using mesh gear instead of another provider’s point-to-point links saves them 65%.

Another advantage of mesh topology is the ability to grow the network incrementally, as security needs change or new funds become available. I’ve heard of quite a few customers who start their networks as a few point-to-point links, or point-to-multipoint, and then reconfigure the networks to full or partial mesh – by filling in coverage gaps with additonal mesh nodes. If they started with true point-to-point equipment, they’d have to rip it out and start fresh.

Many law enforcement customers have mesh gear for portable or temporary deployments; they don’t know what topology they may need for a specific situation. So having the gear that can do all three topologies – point-to-point, point-to-multipoint, and multi-hop mesh – is a big advantage for them. Otherwise, they’d have to get three separates sets of equipment, which is two or three times more expensive.

So, the flexibility of mesh allows for ease of installation and can result in significant costs savings. The fact that mesh can be deployed in multiple configurations, and combinations thereof, is an advantage that many Firetide and non-Firetide customers appreciate.

Updated on April 6: I’ve done a post on limitations of point-to-point and point-to-multipoint systems for video in the post below:

By: Ksenia Coffman – Connect with me on Twitter or LinkedIn.

April 1, 2010

Primer on Twitter Chats

Filed under: B2B,Social Media — kseniacoffman @ 8:04 am
Tags: , , ,

Follow #B2Bchat on TwitterIf you follow me on Twitter, you may have seen me occasionally post with a #B2BChat hash tag, and perhaps wondered what this was about. #B2Bchat is a weekly conversation for B2B marketers, and I’m one of the four co-moderators. The objective is to bring B2B marketing community on Twitter together while discussing topics relevant to us as B2B marketers. There are many great chats on Twitter, but none specifically focused on B2B, so the #B2BChat fills this gap.

So you’d like to try out a Twitter chat, but don’t know where to start? This primer provides you with everything you need to know before jumping in.

What is the purpose of a Twitter chat?

Consider it a virtual roundtable – discussion on topics that are of interest to you. I use Twitter chats as an extension of my professional network. Working for a mid-sized company, I have very few marketing colleagues – so chats are a way for me to sound off ideas, ask questions, share observations and receive real-time feedback.

How are the chat weekly topics determined?

The topics can either be announced ahead of time (as we do with #B2Bchat), focused on trends of the day, or based on questions submitted by the chat community over the course of the week.

How do I join a Twitter chat?

Follow the hash tag in your Twitter client, and add the hash tag to your tweets if you want to participate in the conversation. Alternatively, you can use a web application called TweetChat (http://tweetchat.com/): log in with Twitter, then enter the hash tag – without the # sign – and you’ll find yourself in a virtual chat room, where tweets are automatically filtered for the hash tag you entered. If you use TweetChat, you don’t need to add the hash tag to your tweets; they are added automatically. If the chat is busy, I also open up the twitter home page and set a search for my @handle – so that I don’t miss messages directed at me.

Any tips on participating in a Twitter chat?

Just jump in – respond to messages, share your thoughts on the questions posted by moderators, throw out additional questions. You can also ‘favorite’ tweets that you’d want to go back to, or from someone you’d like to follow after the chat. Note that some of the long-standing chats, e.g. #Journchat or #Blogchat, can be extremely fast paced, so you may want to try out a chat with a more measured pace, such as #B2Bchat (hint hint).

If you are worried that excessive tweeting during the chat will irritate your followers, use this technique: start all of your statements with the chat’s handle (@b2b_chat); that way, only people who follow both you and the chat account will see your message. Same applies when you reply to other participants in the chat. If you want to completely separate your chat activities from your regular twitter presence, you can set up a different account for chats only.

What other chats are out there?

There are many chats in the Twitterverse. In addition to #B2Bchat, I also participate in the following chats on a semi-regular basis:

  • #Blogchat Sunday 9 pm ET Weekly chat to discuss blogs and best practices
  • #ARchat Tuesday 12 pm ET Weekly chat focused on analyst and influencer relations
  • #journchat Monday 8 pm ET Weekly chat between PR professionals, journalists and bloggers
  • #pr20chat Tuesday 8 pm ET Community focused on discussing how social media influences PR
  • #IMCchat Wednesday 8 pm ET IMCchat is focused on integrated marketing and communications.

For more marketing, PR and social media chats, see this article. For a complete list of twitter chats (some inactive) see the Google Doc spreadsheet created by Robert Swanwick (@SpkrInteractive).

A side benefit of Twitter chats is that they allow you to connect with like-minded people, resulting in a growth of your Twitter network; that’s how my personal account (@kseniacoffman) overtook Firetide’s corporate account (@firetide) in terms of followers.

With this primer on Twitter chats, I hope you will join us for the next #B2Bchat this Thursay April 1 at 8 pm ET. This week’s topic: Integrating Podcasting and Video Into Your B2B Marketing Mix. And follow @B2B_chat for updates on future chats.

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