Aruba turned some heads last year when they announced a new product line for SMB, called InstantON. Read more about my experience…
All In All, You’re Just Another Brick In the Wall
How I learned to stop worrying and love predictive modeling
Due to this topic coming up regularly in the community, I’m posting this slightly edited version of one of the project documents I submitted as part of my CWNE application. The building in question has since been completed, but I have not had a chance to go see how the wireless ended up being implemented.
When I was working at Servant42, we were approached by another wireless integrator that we had met at a conference, and I was tasked with taking a preliminary design for a $125M academic research building currently in the early stages of construction, and come up with a usable wireless design in order for the integrator to plan cable placement. The RCDD who did the initial cabling design had put together a grid overlay of access points over each floor, and requested an outlet at each one. The integrator knew this wasn’t going to provide for functional Wi-Fi, and sent over the plans, with a note to pay very close attention to some of the wall types.
The prints were exceedingly detailed, and the wall type schedule alone covered multiple sheets. Not having any real-world walls in this facility to measure attenuation with, I had to rely on published materials regarding attenuation of each type of common construction material. A valuable resource in developing this attenuation model was a 2002 paper[1] published by Robert Wilson (then a graduate student at USC, now a staff engineer at Qualcomm). Based on the various wall types listed on the sheet, I painstakingly added up all the attenuation values and created a wall type for each one in Ekahau Site Survey Pro, labeled to match the callouts on the prints. It wasn’t perfect, but it would get me within about a dB. Some of the walls I had to deal with:
- 2-hour rated walls, with double-thick 5/8” drywall on each side, filled with fiberglass
- Single layer drywall on only one side, open on the other, or wrapping a column
- Filled concrete block
- Cast concrete
- Security walls (more on that in a minute)
- Low-E glass curtain walls
- And so on…
Each of these wall types was also found in varying thicknesses throughout the building. As it turned out, the walls the client was telling me to pay special attention to were the security walls. Several areas of this building were slated to house medical laboratories, and as part of the security specification, it called for steel strapping, “to prevent penetration of a 100mm sphere.” This oddly specific requirement sounded like they were trying to stop small cannonballs, and I was more than a little curious because the specification didn’t mention anything about the velocity of said sphere.
The prints showed 6” wide 54mil steel straps spaced 3.75” apart (95mm) all the way up to the ceiling. And there were a LOT of these walls in the building. The nature of these walls is also such that they were certainly going to be grounded:
So I start digging back into the recesses of my brain where the RF theory is stashed, and consulted an RF engineer colleague, where he gave me a refresher on the RF transparency of various openings, where odd numbers of quarter waves are opaque to an RF frequency and even numbers are transparent. Some quick calculations told me that my 95mm openings were almost exactly ¾ wave on 2.4GHz. And because they ran horizontally, the gaps were about 16” wide between studs. So these lovely security walls were going to be opaque to 2.4GHz, but only one way. And transparent to 5GHz. Welcome to my nightmare! How in the heck was I going to model this? Ekahau didn’t give me the option for different attenuation values for frequencies or polarization.
Wilson’s paper also didn’t make any mention of this sort of thing. And I still couldn’t go out into the field to measure it, nor did the client have the budget or the time for us to set up a model of the wall and test that.
As I’m trying to figure out my next move, I get a call from the client, and he tells me they’re starting to build those security walls on one of the lower floors. And then he sends me this picture. Sure enough, they deviated from the version of the plans that I had, and used an entirely different construction material on the security walls: an expanded metal diamond mesh rather than strapping, the type once commonly used as lath for plaster walls in the 1940s after wood lath fell out of favor (I’ve had to add data drops to those walls and cut in boxes, it’s NOT fun.)
So now my calculations are out the window and I have to start over. I try to estimate the size of the holes in this mesh. I come up with about 6mm based on some rudimentary photogrammetry. This hole works out to 1/8 wave in 5GHz, and 1/16 wave in 2.4GHz. As far as the Wi-Fi is concerned, these might as well now be brick walls. I still don’t have a true idea of the actual attenuation. So I assume at this point that a layer of this stuff is going to stop the signal dead and dump it to ground, and put in 20dB. But at least I can model these now.
Now that I can put all my walls in, I build the model in Ekahau (and I was really wishing for a CAD file at this point) and I’m able to model the existing planned AP locations, show the numerous coverage problems caused by the security walls, and then re-plan the whole building (four occupied floors and a basement, including a few high-density lecture halls). Coverage was defined by the client for Cisco 3802i APs with -67dBm primary coverage, -75dBm secondary coverage, and not to worry about voice. Lecture halls needed to assume 2 client devices per seat.
In several locations, I was having to place an AP just to cover a small pair of offices, because they were wrapped on three sides with these security walls. In a few cases, the office itself was fully wrapped in these secure walls, with a solid core door and safety glass window to the hall. I decided not to model the window and doors into the outer halls as the RF spilling from them would not be relied on for coverage outside the office. I made the recommendation to run these APs at lowest possible output power and specified a separate AP to cover these halls, preferably with a directional antenna. In other places, I had to place APs to cover RF shadows left by these walls.
Once complete, the client was then able to go back to the RCDD and request the additional cabling drops for the access points (the AP count through the entire building increased by nearly 50% just to deal with these Wi-Fi-eating walls)
[1]Wilson, Robert, “Propagation Losses Through Common Building Materials: 2.4GHz vs. 5GHz”
What’s In Your Go-Kit?
As I prepare for another trip to a customer site, I figured I’d post the contents of my wireless engineering go-kit for the benefit of others wanting to put one together. I’ve posted previously about my streaming go-kit, which has largely been retired as I’m not doing nearly as much streaming as before, having shifted over to Wi-Fi. Amazon links in this post are affiliate links, and it’s where I bought most of this stuff over the course the the last several years. Some of it was freebies from conferences like the Wireless LAN Professionals Conference.
What’s in the kit?
It will depend largely on the job I’m going to do, but I’ve got several sub-kits that go in it based on the needs of the job:
Frame Analysis Sub-Kit:
(this kit has largely been deprecated by my Macbook and Airtool)
- 3 Netgear A6210 2SS 802.11ac adapters for use with Omnipeek – I don’t know if the 3SS version A7000 has requisite drivers for Omnipeek. Word on the street is that Metageek EyePA recently added support for these adapters. AirMagnet can also use these for surveys.
- 1 AirPCAP Adapter for use with Omnipeek (pretty much obsolete at this point)
Site Survey Sub-Kit:
- (I hope to be able to replace this kit with a Sidekick sooner than later!)
- 3 Ekahau/Proxim NIC-300 adapters
- Anker USB 3.0 Hub
- HubHolster clips
- WLAN Pros Site Survey Tray/Walking Desk (this has to go in checked luggage due to size – which is where an airline with a generous baggage policy comes in handy, or frequent flier status that gets you checked bags)
Spectrum Analysis Sub-Kit:
Pentest Sub-Kit:
- Hak5 Pineapple Tetra Tactical Kit
Ethernet/Console Sub-Kit:
- 3 AirConsole Mini 2.0 wireless console adapters
- 2 Apple USB Ethernet Adapters
- 1 Apple Thunderbolt Gigabit Ethernet Adapter
Test Tools:
- Netool.io NE1 network tester
- Fluke/Netscout LinkSprinter 300 network tester
- Optical light source/power meter
- Fluke Pro3000 Tone/Probe Set (I’ve forgotten to bring this WAY too many times, it’s a lifesaver)
Measurement/Installation Tools:
- Bosch GLM100C laser measurement
- Bosch GLL55 Laser level
- iFixit 64-bit driver kit
- Panduit EGJT termination tool (Doesn’t hurt to carry a handful of spare jacks too) – this takes up way less space/weight than a bag of 8P8C plugs and a crimper, and results in a much better connection.
- Klein electrician’s scissors
- Klein 11-in-1 screw/nut driver
- Nite Ize Gear Ties
- Gerber Remix Tactical Knife
- Brother P-touch Edge label printer (although thinking of replacing this with a PT-700).
Miscellaneous:
- Power Tap/Surge Protector
- USB Charger (I carry the Apple 29W charger because my iPhone X and iPad Pro support USB-C PD and I don’t have one of the new MacBooks that uses USB-C – I can go from dead to a near full charge on my phone in about an hour, and the iPad charges wicked fast as well. I can also use this to power the USB3, HDMI, and USB Ethernet dongles off my iDevices, all at once)
- USB Cables (I love me some Anker cables)
- SD cards (In Pelican 0915 SD card case)
- Ethernet patch cables
- 10′ Slim HDMI cable (for presentations or watching Netflix in the hotel room!)
- Outlet/GFI tester
- Sharpies
- AA Batteries (your tone/probe set will need 9V, but not often)
Computing:
- Microsoft Surface Book
- Apple MacBook Pro 15″ (upgraded to 802.11ac)
- Apple iPad Pro 10.5″
Software:
- Ekahau Site Survey Pro (Mac/Windows)
- Savvius Omnipeek (Windows)
- Metageek EyePA (Windows)
- Metageek Chanalyzer (Windows)
- Metageek InSSIDer Office (Windows)
- AirTool (Mac)
- Wifi Explorer Pro (Mac)
- Wireshark (Mac/Windows)
- Microsoft Visio (Windows)
- Microsoft Office (Mac/Windows)
- Microsoft OneDrive (Mac/Windows) (good for sharing frame captures and design files between systems)
PPE/Safety
- Fall Protection harness (required on boom lifts) with lanyard
- Hard Hat (If I’m flying, I try to obtain one at my destination, either at the jobsite or Home Depot
- Z87.1 Safety Glasses (polarized shaded glasses really help on a rooftop in blazing sun)
- OSHA 10-hour Construction Safety Certification
- OSHA Aerial Lift Training & Certification
- First Aid/Trauma kit
Depending on the combination of stuff, most of it goes in a Pelican 1510 carry-on case (yes, it all fits – other than the PPE – with some room to spare, especially if you add the lid organizer, which is great for keeping small things contained!) . Because some of the devices in there contain lithium batteries, I can’t check it – but in that case the scissors and the knife need to go in checked luggage – But if you do some mental calculations and add up what all this stuff costs, you’ll see that even without the computers and software, that’s not generally something I am willing to let out of my immediate control. I don’t bother with TSA locks, because those don’t provide any security.
If I only need some of the items, I put them in a smaller nylon case that used to be a carrying case for a projector, which does fit in a checked suitcase. The fiber kit has a dedicated Pelican 1490 case when not traveling in the 1510.
A Story of Cats
This is the internet, so at some point we’ve got to talk about cats. It’s in the rule book. The Internet runs on cats. Cat pictures, cat videos, and… cat cables.
Those of you not familiar with the intricacies of the first layer of the OSI “7-layer Burrito” (Internet old-timers will remember this) are probably blissfully unaware of the gory details of the wiring that makes everything (including wireLESS) work.
So who are all these cats, anyway?
Simply put, it’s an abbreviation for “Category”. The Telecommunications Industry Association (TIA) has adopted a series of specifications over the years defining cable performance to transport various types of networks.
Here’s a quick rundown. We’re gonna get a tech lesson AND a history lesson all rolled into one.
Category 1 (pre-1980)
This never officially existed, and was a retroactive term used to define “Level 1” cable offered by a major distributor. It is considered “voice grade copper”, sufficient to run signals up to 1MHz, and not suitable for data of any sort (except telephone modems). You could probably meet category 1 requirements with a barbed wire fence. You laugh, but it’s been done. Extensively.
Category 2 (mid-1980s)
Like Category 1, never officially existed, and was a name retroactively given to Level 2 cable from said same distributor. Cat2 brought voice into the digital age. It could support 4MHz of bandwidth, and was used extensively for early Token-Ring networks that operated at 4Mbps, as well as ARCNet, which operated at 2.5Mbps on twisted pair (it had previously used coaxial cable).
Category 3 (1991)
This is the first of the cable categories officially recognized by TIA. It is capable of operating 10Mbps Ethernet over twisted pair (like ARCNet, Ethernet also ran on coaxial cable in the very early days). Category 3 wire was deployed extensively in the early 1990s as it was a much better alternative to 2Mbps ethernet over coax. This is where the now nearly ubiquitous 8P8C connector (often incorrectly referred to as “RJ45”) came into usage for Ethernet, and it’s still in use nearly 3 decades later. Both the connector pinout and the cable performance are defined in TIA standard 568. Since token-ring networks still operated at 4Mbps, they ran quite happily over this new spec. In 2017, one can still occasionally find Cat3 in use for analog and digital phone lines. The 802.3af Power over Ethernet specification is compatible with this type of wire.
Category 4 (early 1990s)
This stuff existed only for a very brief period of time. In the late 1980s, IBM standardized a newer version of Token Ring that ran at 16Mbps, which required more cable bandwidth than what Category 3 could offer. Category 4 offered 20MHz to work with (which may sound familiar to the wifi folks, who use 20MHz channels a lot). But Category 5 came along pretty quickly, and Category 4 was relegated to history and is no longer recognized in the current TIA-568 standard.
Category 5 (1995)
TIA revised their 568 standard in 1995 to include a new category of cable, supporting 100MHz of bandwidth. This enabled the use of new 100Mbps ethernet (a 100Mbps version of Token Ring soon followed, which also used the same 8P8C connector as Ethernet).
Category 5e (2001)
TIA refined their spec on Category 5 to improve the performance of Category 5, to support the new gigabit ethernet standard. It is still a 100MHz cable, but new coding schemes and the use of all four pairs allowed the gigabit rate. IBM and the 802.5 working group even approved a gigabit standard for token ring in 2001, but no products ever made it to market, as Ethernet had taken over completely by that point.
Category 6 (2002)
Not long after Category 5e came to be, Along comes category 6, with 250MHz of bandwidth. This was accomplished partly with better cable geometry and by going from 24AWG conductors to 23AWG. This increased bandwidth allows 10Gbps ethernet to operate on cables up to 55 meters in length.
Category 6a (2009)
This refinement to Category 6 increased cable bandwidth to 500MHz in order to allow 10Gbps ethernet to operate at the full 100m length limit for Ethernet. Categories 6 and 6a will support the new 802.11bt Power Over Ethernet Level 3 (60W) and Level 4 (90W) standards (expected 2018) provided that cable bundles do not exceed 24 cables for thermal reasons.
Category 7/7a
This one never existed in the eyes of the TIA. It still lives as an ISO standard defining several different types of shielded cable whose performance is comparable to Category 6 (bandwidth up to 600MHz for Cat7, 1GHz for Cat7a). Both these specs were rendered moot by 10Gbps Ethernet operating on Category 6a with standard 8P8C connectors. This cat was so ugly, TIA left it at the shelter.
Category 8 (2017)
The latest and greatest, this cable exists to run 40Gbps ethernet. It comes in two flavors, unshielded as 8.1, and shielded (supplanting the Category 7 specs) as 8.2. This cable has a bandwidth of 1600MHz for unshielded, and 2000MHz for shielded.
So there you have it. The cats that put the WORK in “Network”. And because this is the internet, I leave you with gratuitous kittens.
Streaming Church to Facebook Live
Note: Somehow this got stuck in the publishing queue and never got the green light… So here it is, a few months after writing, but still relevant…
This past weekend saw much of the upper midwest plunged into an arctic deep freeze, leading many churches in the region to cancel services (we woke up Sunday morning to temperatures near -10°F and a stiff wind). I saw many pastors on my Facebook feed wondering if there was a way they could do church using Facebook’s relatively new live video feature.
Short answer: Absolutely.
But there are a few caveats in order to make it a good experience. With a little bit of advance planning, you can be prepared at very little cost. I’ll go over a few of the ways you can do the Facebook Live “thing” in increasing order of complexity.
Getting the video signal to Facebook
Using your smartphone and its onboard camera
This is the basic method that Facebook has in mind for its streaming service – people sharing live video on the fly. Whether you use an Android phone or an iPhone, these apply (mostly) equally.
- Remember that your phone’s camera has a wide-angle lens. These are designed for those great landscape and sunset shots. All fine and good, but if you’re going for a tight shot, you have to get REALLY close. (The iPhone 7 Plus also has a 2X camera that works very well at longer distances)
- Keep the phone steady. Ideally, some sort of tripod mount. These can be had on Amazon for under 10 bucks. My personal favourite is the Ztylus Z-Grip (Amazon, $10) which has a cold-shoe adapter (more on that in a bit). I also really like the Reticam Smartphone Tripod Mount (Amazon, $25) as it is an all-metal mount and is very durable. These will support a phone on even one of those little tabletop tripods.
- Audio. Let’s face it, the onboard microphones on smartphones are terrible. They’re designed to capture sound close up.
- If you’re doing a tight shot while preaching from home in your pajamas (I won’t tell!), a simple lapel mic such as the Audio-Technica ATR3350 (Amazon, $30) will do wonders for your sound quality (They also offer a “Smartphone” version of the ATR3350 that comes bundled with a mic/headphone splitter).
- If you want to use an existing microphone, you’ll need to get a splitter for your headphone jack that breaks it out to separate headphone and mic jacks (Amazon, $7) and use a 1/8″ to XLR cable (available just about anywhere).
- You can also use a shotgun microphone designed for a DSLR that has a 1/8″ jack on it. I like Røde mics for this (and these mount to the cold shoe on the Ztylus grip) such as the Røde Video Mic Go (Amazon, $100) or any other shotgun. If you have an iPhone 7, there are a few out there with a direct lightning interface.
- If you wish to interface your phone to your church’s existing sound board, you have a few options. If your board offers a mic-level output, you can bring it straight in. If it offers line-level output (like most), you can use a DI box to convert it to line level or use a device like the BeachTek DXA-SLR-ULTRA (Amazon, $300) I also have a used one of these for sale. Contact me if you’re interested. If you’re coming off your sound board, it’s good to have a separate mix that gives online viewers a better audible context of the room. This is especially important if you’re using acoustic instruments that don’t necessarily need to be amplified.
- Lastly, if you’re preaching from home, try to minimize external noise.
- Lighting. Most camera phones have very small apertures, which means they don’t collect as much light as a bigger camera, so you need to have your subject well-lit for good video. This is a good time to familiarize yourself with the basics of three-point lighting.
- Power. Make sure your phone is plugged into power before you do this. Video and live encoding is murder on a battery.
- Bandwidth. Unless you really love sending your cell carrier lots of money or have an unlimited plan with really good LTE coverage, do this over wifi. Make sure your outbound bandwidth is sufficient (Facebook app typically streams at 2Mbps).
Using a tablet
Much of the smartphone discussion applies here as well, but consider that most tablet cameras simply aren’t as good as their smartphone brethren. Naturally, you’ll need a bigger tripod mount (and a tabletop tripod likely won’t cut it anymore).
Using an iPad opens up an additional production option with Teradek’s Live:Air application which allows you to add titles and such to your stream, as well as bring in additional camera shots from other devices including other iPhones. The Live:Air Solo app for iPhones does not allow streaming to Facebook because of an obscure clause in the Facebook Terms Of Service that prohibits streaming to FBL via third-party phone apps (but not tablet apps).
Using a DSLR or other video camera
If you already have a “good” camera such as a DSLR or a Semi-pro/Pro grade video camera, you can take the SDI or HDMI output from the camera into an encoding appliance such as the Teradek VidiU Pro (Amazon, $999), which will support streaming to Facebook directly without the need for a smartphone or a laptop (although you will need one to set it up).
If you prefer to use a computer with a capture card (Mac: BlackMagic Design Ultrastudio Mini Recorder, $140, Windows: BlackMagic Design Intensity Shuttle for USB 3.0, $190). You can then use Wirecast software to publish to Facebook. You can also do this with a USB webcam, but the results won’t be great.
Using your existing video system
If your church is a little more sophisticated and already has a video switching system, it’s relatively easy to use an encoding appliance or software as previously mentioned.
But I’m already streaming!
Great! you’ve mastered most of the technical stuff already, you just want to add Facebook as an additional outlet. This can be accomplished in Wirecast simply by adding another publishing destination. If your encoding software doesn’t let you do that (or you’re using an appliance with a single destination), you can use Wowza Streaming Engine or Wowza Streaming Cloud as an initial publish point and then use it to send your stream to multiple destinations. That’s a little beyond this blog post, but it’s not especially complex.
OK, that’s the easy technical part. Now comes the fun stuff:
Legal Considerations
If all you’re doing is preaching over Facebook, you’re in the clear. Unless you’re showing pre-recorded video illustrations that you didn’t create. If you’re performing music in church, you’ll need a streaming license. If you’re using pre-recorded music, that music needs to be licensed with a “sync license”. The good news is that the sync license is the responsibility of the site where the stream is published, so in the case of Facebook or YouTube Live, Facebook and Youtube need to get those licenses (and they have them, since they’re the ones monetizing your content)
If all you have is the standard CCLI license, this does NOT cover streaming. This is only a “mechanical license” that allows you to reproduce the song lyrics, whether in the bulletin or on your screen. CCLI and CCS both offer blanket streaming licenses that cover you.
Also bear in mind that if you are using a smartphone camera, Facebook’s TOS do not allow live streaming from any applications other than Facebook’s own app. Tablets and computers are another matter entirely. Check into Teradek’s Live::Air suite of applications (think Wirecast, for your iPad, using iPhones as remote cameras)
Analytics
One of the great benefits to video streaming on Facebook is the analytics you get from it. For more details, check out this page from Facebook about live video analytics.
Streaming on the go
Over the past several months/years, I’ve been accumulating various pieces of gear that, when put together, give me a solid kit to take on the road for doing onsite streaming or demonstration events. It currently consists of:
- 15″ Retina MacBook Pro, with WireCast Studio
- iPad (4th Gen)
- AKG K 44 Headphones
- Blackmagic Design UltraStudio Mini Recorder (SDI/HDMI to thunderbolt)
- Blackmagic Design Mini Converter HDMI to SDI
- Blackmagic Design Mini Converter Analog to SDI
- Teradek Cube 155 Streaming Encoder
- Teradek VidiU Streaming Encoder
- M-Audio M-Track Plus USB Audio Interface
- HP ProCurve 1810-8G gigabit network switch
- Aerohive BR100 Router
- Novatel USB551L USB LTE Modem (Verizon)
- Zoom H1 Portable Digital Recorder
- HooToo USB 3.0 4-Port Hub
- Canon HF-R200 Camcorder with GoPro Mount Connection to 1/4-Inch Camera Adapter
- GoPro HERO3 BLACK with various mounting accessories
- Anker Astro Pro2 20000mAh External Battery Power Bank
- Assorted USB sticks, SD cards, MicroSD cards, and interconnect cables.
I still probably should add an SDI Distribution Amp to the kit, but I haven’t had need for it… yet.
The Canon and GoPro each have their own Pelican 1200 cases, and don’t travel with me unless I need to provide cameras (usually I’m getting a feed from video world and streaming it from there). The SD cards travel in a Pelican 0915 case, which is along with the rest of the gear in a Pelican 1510.
I love the Pelican 1510 – It’s legal carry-on size, so when traveling, all that expensive gear is never out of reach, never at the whims of a sticky-fingered TSA agent or baggage handler inside the bowels of the luggage system where nobody can see them. When flying, I’ll take the Pelican and my laptop bag with me, my clothes go as checked luggage (yay for airlines that give me free checked bags!). I modified the 1510 to include a mesh organizer in the lid instead of the egg-crate foam that it normally comes with, which lets me keep track of the various small bits that go with all that gear.
(because the foam inserts are removable, the 1510 along with a borrowed 1610 came in very handy this past summer when I was on vacation and traveling on a float plane – in case my luggage got dunked in the drink, the cases would float and my clothes would stay nice and dry. Pelican also makes a luggage version of the 1510. I love Pelican cases.)
Here’s the problem with all that gear though: Except for 1 or 2 devices, every single one of them requires a “wall wart” power adapter. There’s no room in that case for the several power strips that I’d need to do this in a self-contained manner, where all I need from the venue is an outlet and (optionally) an ethernet drop. Additionally, all those adapters in the lid make for a huge jumbled mess on the TSA’s x-ray machines, so more often than not, they want to take a look inside, and swab it for residues. I got to looking at the gear and realized that every single piece of it that used external power would accept a 12VDC input, and they all even shared the same polarity.
[table id=2 /]
Another thing I discovered along the way is that manufacturers rarely specify the details of the DC connector beyond the voltage and only occasionally the current draw. Trying to get connector information from vendor specs is a pain in the rear. This sucks if you have to order a replacement power supply because yours broke or got lost. With the help of a pair of calipers and some trial and error, I was able to figure out what each one was.
I started hunting around for 2 items: A distribution bus, and a compact 6A (or bigger) DC power supply.
The DC bus proved to be problematic, until I hit upon the right combination of keywords that revealed what I needed on Amazon: an 8-way fanout meant for use on security cameras, which had the 5.5×2.1mm connector that I’m discovering is nearly ubiquitous. Bonus: I didn’t have to make my own splitter.
On the power supply front, I found several meant for A/V use, but all of them were large and not well suited to portability. I found my solution on eBay: There is an endless variety of OEM laptop power supplies that put out 12V and 6A. Many of them are sold as an “LED Power Supply”, and run about 10-15 bucks. I found one that had the same 5.5×2.1mm connector that all my gear needed. Due to difficulties in getting the calipers down inside the connectors, I initially thought the BMD converters were 5.5×2.1mm, but they’re 5.5×2.5mm, and the center pin is too fat – but 5.5×2.5mm female connectors will also accommodate the smaller 2.1mm pins just fine. I should have ordered a 5.5×2.5mm fanout instead. Lesson learned. In order to adapt the 5.5×2.1mm splitter to the various devices, I dug around amazon to find the various adapters I’d need. The only problem is the Lemo connector used by the Teradek Cube: Those locking connectors are $100 each. Ouch.
By a happy coincidence, my wife has a battery booster pack in her van that is float-charged by a 12V connection, which also happens to be 5.5mmx2.1mm. I recently had to order a replacement CLA adapter for it, and picked up an extra one, which would allow me to run this whole streaming rig from automotive, solar or battery power if needed. The whole setup draws about 70W at full load if all of it is running.
I also ordered (but haven’t yet received) a female 5.5×2.1mm to CLA socket, so that I can pop in a CLA USB charger to power my iPad, charge the GoPro, and other USB devices so I don’t eat up a port on the computer just for power, as I’ve only got two.
(As a side note, Ruckus/XClaim and AirTight access points also use 12V 5.5×2.5mm connectors as an alternative to PoE, but if I need wifi the AeroHive unit will do the job. Aruba APs use a smaller connector, whose dimensions I am presently unsure of)
Now my whole rig can be run off two AC outlets (plus a third until I can somehow find a cheaper Lemo connector!). I think the next step is to find some sort of way of putting a battery inline, effectively giving me a UPS for the whole stack (although the laptop , iPad, and the Teradek units all have internal batteries as well) Edit : I since acquired an Anker Astro Pro2 External Battery which has not only the ever-convenient 5.5×2.1mm 12V input socket, but also a DC output (which includes an adapter that goes from the battery pack to a 5.5×2.1mm output plug) that effectively turns this into a 12V UPS which can deliver up to 22W on the USB ports and 18W on the DC port (which is selectable between 9V and 12V), meaning a 10 hour runtime at full load. The unit is only slightly bigger than a small tablet. I can’t run ALL the gear on it at once, but I can at least put the really critical stuff on it. The 1st-generation model of that charger has a beefier 48W DC output that can go to 16V and 19V to power laptops.
Here’s the DC parts list, with links to Amazon:
Gear: Teradek VidiU – First Look
I recently got some Teradek gear to try out in a church setting, and I will be posting a few blog posts about it. Other than loaning the gear, Teradek is not compensating me for this. I am, however, more than happy to sell Teradek hardware to anyone that wants to buy it from me.
First up: The VidiU, Teradek’s low-cost offering at $699.
When you open the box, the unit is right on top, nestled comfortably in a piece of high-density foam. Underneath is the power supply (with plugs for just about every electrical outlet in the world), a 1-meter ethernet cable, and a 50cm HDMI to mini-HDMI cable suitable for connection to a variety of small cameras. There is also a small adapter for mounting the VidiU to a camera shoe or a tripod mount.
The unit itself is a plastic case slightly larger than a deck of cards. On the front is a small OLED display with a couple of buttons. On the left is a sliding power switch (love this, very difficult to accidentally turn off by pushing a button), a USB port for connecting a 3G/4G modem, and a headphone port for monitoring audio. on the rear is a full-size HDMI port, a 1/8″ jack for connecting either a microphone or line-level signal, a recessed reset button, the ethernet port, and a standard coaxial power connector for a 6-12V DC input. I did discover that the power plug can come unplugged fairly easily. Fortunately, the unit has a built-in battery, so you don’t need to be tethered to power, although I’m told the battery is limited to about an hour of runtime and is best suited for keeping it running while swapping power supplies. When plugged in, the internal battery will charge (there are power and charge indicators just below the ethernet port). When charging, it draws about 10W, and about 3W when operating on a full charge. This means you could conceivably run this unit on solar power without much difficulty. More on that in a future post.
When you first power it up, it will search for a network. When it can’t find one that it knows about, the display prompts you to press the Menu button. This little black button (one of only two on the device) is more than meets the eye, and is actually a tiny 4-way joystick in addition to being a button (as is the red start/stop button above it). The setup for connecting to an existing wifi network is fairly intuitive, but due to the limited number of buttons, the process of entering wifi passphrases and URLs for your publishing point is somewhat tedious. The MIMO wifi supports both 2.4Ghz and 5GHz bands.
The easiest way to set up the VidiU is to connect it to the network via a wire (the battery comes in handy here), log into the web interface and do the configuration that way. Getting the DHCP address could be a little tricky, and the recommended process is to use the iPhone app. When I tried the app on my iPad, it gave me the IP address, but most times when I tried to connect via the iPad, the entire web UI crashed on the unit requiring a power cycle. The Android app didn’t fare any better on my Samsung Galaxy S4.
The VidiU comes preconfigured to use LiveStream, Youtube Live, UStream, and Twitch, as well as a manual configuration that lets you use any RTMP server such as Wowza Streaming Engine. If you’re using Wowza, make sure you set the agent to FMLE, since by default, Wowza rejects publisher user-agent strings that don’t look like FMLE.
Once it’s configured, streaming with the VidiU is as easy as pushing the start/stop button on the front, although a quick press doesn’t do it, you need to hold it for about a second for it to do anything, and if you hold it for too long, it will ask you if you want to turn off the display.
I tried it with a variety of sources, including as a mirrored display on a Mac Mini (great for screencasts), a Roku (which was temperamental at best), and a standard video camera (the easiest of all configurations). Switching HDMI cables while it’s streaming is not recommended. Doing so crashed the unit once, and confused it on 2 more occasions requiring a reboot.
The built-in quality presets are as follows:
- Full HD (1920×1080, 5.2Mbps)
- HD (1280×720, 2.2Mbps)
- High (960×540, 1.4Mbps)
- Medium (736×414, 800Kbps)
- Low (480×270, 450Kbps)
- Mobile (360×200, 275Kbps)
If you’re unsure about your connection, it has a built-in speed test that can check your bandwidth and make a recommendation based on the results. There is also an adaptive bitrate option which will adjust the settings to match available bandwidth.
Wowza Stats – Single Server
Here’s the code for gathering Wowza Stats from a single server. This assumes that you’ve enabled the stats on Wowza (serverinfo, connectioncounts in VHost.xml HTTPProviders), with authentication turned off). You’ll also get better detailed stats if you use Andrew Kennedy’s CasterStats module for the serverinfo.
Site Migration Complete
Got all the pages moved over and the images all fixed, and took care of a number of broken links. If you see any problems, let me know.
Site Migration
In the process of moving the site to a new hosting provider – bear with me. Still working on moving the images, they’ll start cropping up over the next few days.