Aligning an 80GHZ link at a mile and other licensed backhauls

Recently we had a teaching moment for a couple of folks who had not had much experience with aligning higher frequency antennas with very tight beamwidths.  This particular day we were aligning 2 foot Siklu 80GHZ antennas.

One of the questions we often get asked is how do you align these? These questions are usually asked by someone who is familiar with aligning 5ghz antennas with a 10 or 20 degree beam which you can eyeball and has tried a microwave shot. They find out it is much harder.  The higher you go in frequency the tighter and smaller the beam is.  Distance also affects how far off you can be.  Think of it as a laser pointer.  If you have ever taken a laser pointer out at night and shone it a long distance you will notice even the slightest movement will cause it to jump inches, even feet.  Keep laser pointer analogy in mind for this next section.

In order to understand alignment, we need to understand lobes on an antenna. An antenna is just a device that focuses radiation in a direction.  In a licensed microwave setup, these antennas focus the radiation in a tighter “beam”.  Let’s go back to our laser pointer analogy.  Some laser pointers project a smaller dot at 10 feet than others.  Same for antennas.   The diagram below shows what is called the main lobe and the side lobe.

The way to get the best signal is to get both dishes locked on to the main lobe. Sounds easy right? With higher frequencies, you are talking about millimeter waves. This means the main lobe may only be 3mm wide, about the size of this text on a laptop screen.  Now imagine trying to keep that 3mm beam in the center of a paper plate at a mile.  On top of that, the difference between the main lobe and locking onto a side lobe could be the difference of 1-2mm. A slight wind can move a dish 2mm.

To give you a real-world example. A 2ft 23 GHz antenna having 3 dB beamwidth of 1.6 degrees. Allowing for a path length of about 2.5 miles (this is licensed 23GHZ) the actual beamwidth at the receiving antenna is around 370 ft and is, therefore, likely to be greater than the height of the tower. If the antenna’s out of horizontal by even a couple of degrees to start, the antennas will miss by around 460 ft and not be able to “see” each other. This can be amplified as frequency and distance increase.

This is all fine and dandy, but what about the practical world? How do I align the thing?
It all starts with the FCC path coordination paperwork you will receive on your licensed link. There is a wealth of information in here.  It tells you all of the following:
-Your mounting height (this is typically already known)
-Your heading (more on this in a bit)
-The antenna angle downtilt or uptilt (very important)
-The expected signal target

Armed with this information you will have all of the information you need to align the link.  From this point, the philosophical side of things kicks in.  Some tower climbers are good with using a compass to get their exact bearings.  Others have high dollar tools to do it all via GPS such as microwave path alignment from Sunsight.

What everyone doing alignment should have in their toolkit are the following:
-A small magnetic bubble Level. We want to make sure we start with a level mount.  We would be fighting an uphill battle if the pipe or standoff we are mounting to is not level.

-An angle Finder is very helpful for determining the antenna down or uptilt per the path calculation.

Obviously, the above tools are just one of many examples.  There are more expensive ones and bare bones ones.  Tools are only as good as the person using them.

-Ratcheting wrenches for the left and right and up and down adjustments.
Having ratcheting wrenches makes fine-tuning a very easy process.  You will see why later.

-A good hands-free communication method.  Depending on the tower FM communications may or may not work.  Cell phones may or may not work. Being able to talk to the crew on the other end is crucial.  And yes, to make this smooth you want a crew on the other end.

Aligning backhauls, especially microwave, is a skilled trade.  With any skilled trade, you will get all kinds of tips and tricks of the trade.  Some you may use, others you may not.  Ask any Carpenter, Drywaller, or Mason and they will tell you little tips and tricks. They probably all are great and will work, but you may only use some of them.  I am going to tell you mine. You may find others you like better.

We always start with a google earth plot of the path. I call this Phase 1.  The goal of phase 1 is to get the radios talking.  We make sure the line is exactly on the two points, not just approximate.  If the backhaul it on the left side of the tower, we draw the line to/from the left side of the tower.  We then pick 2-3 landmarks along the path as we can.  We start with something close to the tower the climber should be able to see.

In our photo above we have picked out two reference points close to the tower the climber can see.  The first is the clump of trees on the climbers left.  The path passes “just to the right” of the edge of the end of the trees.  The second reference is the intersection of the county roads about 2-3 miles out.  Our path should be just to the right of those.  That point of reference is more of a sanity check. More than anything. The climber at the other end has a similar printout.   I have found communication during this process works best if both climbers and someone logged to at least one radio on the ground with a laptop are on a conference bridge.  Many radios have lights, tones, or multimeter outputs to indicate signal.  Some modern radios only have web-interfaces and apps.  Hold a phone while trying to align can be cumbersome.  This is where the guy on the ground can take some load off what the climbers are doing.

Regardless of the mechanics of the radio, the goal of Phase 1 is to establish a radio link, no matter how bad it is. Now, here is where the real meat and potatoes of backhaul alignment come into play.  This is a very deliberate and calculated process.  Your goal at the end of the entire alignment process is to end up with the following diagram

What many folks don’t realize is it is possible to establish a signal on a side lobe. So how do you know if you are on a side lobe? Here is how we start phase 2. This is what I call fine-tuning. Real original huh? Depending on good, or lucky you were during phase 1 you may have a long way to go or a short way to go to meet target.  Remember that in your paperwork we talked about earlier?  One side and one side only starts moving their fine adjustment on their antenna to the left and right and up and down.  This is typically called sweeping.  The key thing to note here is you need to find the very edges of the radio signal, not just the lobe you happen to be on.

Let’s take a real-world example to explain how sweeping affects main and side lobes.  At the start of this article, we mentioned an 80ghz link.  With our phase 1 rough alignment, we were able to get linked at a -86.  The target was a -32.   The first side to start alignment started sweeping to the right, signal started going from a -86 down to a -72 rather quickly. This was using very small turns of the adjustment.  The ratcheting wrench was only clicking 1-2 times for each 2-3 db of signal change. Once it reached a -72 it started climbing back up.   The climber then kept going to the right to find the edge of the signal, not just the lobe we were on.  The signal started getting worse until we were back into the upper 80’s.

Now, the climber brings the alignment back to the left, and stops at the -72 and makes a mental note of where that is in relationship to the overall placement of the dish, etc.  Some mounts have distinct notches, some guys use markers, others just remember.  Now the climber continues on to the left and the -72 gets worse and goes back down to the -86 and continues to get worse.  So the climber, at least for now, has found the sweet spot for the left and right alignment.  The climber also knows this will probably change, but has found it for now.   Climber repeats the same procedure for the up and down. Due to the anglefinder, the climbers have with them they feel pretty confident they are fairly close with the up and down so they do not adjust the up and down travel as much as the procedure goes on.

Next, the other side does the same procedure the first side did. They do the left to right and get the signal down to a -62. Essentially, what the climbers are trying to do is find the center, which will contain the strongest signal, by sweeping past the other signals.  Keep in mind there may be only millimeters separating these other lobes.  Due to physics, and the shape of the signal, the first lobe is actually stronger than the edges of the main beam.

Say what? The first lobe is stronger than the edges of the main beam? Yes, but not stronger than the main beam.  Let’s go back to our installers. They have each had a go around at alignment and are only at a -62.  On a 5ghz backhaul that would be respectable, depending on your noise floor. But we are 30db away from our target of -32. Some climbers, incorrectly I might add, try to do a shortcut by scanning in an x pattern instead of x and y-axis separately. This makes it easier to lock onto a side lobe.

80ghz backhaul

So now our first climber goes back to making the left and right adjustments.   At this point, the installer finds something odd.  He has gotten the signal down to a -55, but that’s the best he can do. Even a small turn jumps the signal up    Then our installer remembers the above statement.  The first lobe is always stronger than the edges of the main beam.  He gets the signal back down to a -55 and turns the alignment over to the other side.

Here is a very important thing to note.  Both of our installers have now “gotten a feel” for the few turns needed to adjust the signal on these dishes.  To them compared to 5ghz dishes, these are very tiny and almost insignificant movements. But they sure make a difference in signal.  Now our installer at tower B has his second alignment session.  As he is making adjustments the signal is not changing.  He is moving his wrench for what seems like forever and the signal is barely moving, Any other time their signal would have been a -90 or dropped.  What has happened here? The main lobe of one side has locked onto the first lobe because it is always stronger.  Since the main lobe is bigger it seems like it takes forever to make any change.  If we had a guy on the laptop he was probably also probably seeing very mismatched data rates.  One side was probably much higher than the other by a large margin.

Then boom, all of a sudden the signal goes from a -55 to a -42.  A 17 db jump!   We can now tell we are on the main lobe.  If the laptop person looks at the data rates now they should be more balanced.

Data Rates on a Mimosa B11 Rates properly aligned but not fine-tuned

At this point, it is just a simple matter of each side making finer and finer adjustments back and forth to get the signal down.  If you think of the above circle/crosshair you are making smaller and smaller adjustments to nudge toward the center of the circle. This is where the ratcheting wrenches help by giving a very measured amount of travel.  This helps with the whole feel of alignment.  Much of it is feel to see how much you can move the adjustment mechanisms to make the numbers move.  Sometimes it may be a single click of the wrench.  Sometimes it may be one or two.  It just depends.  As you get closer and closer to target you are moving the adjustment less and less.

As you get closer and closer to target you need to be thinking about how tightening down the adjustment bolts will affect the alignment.  Even tightening them down snug can affect the signal.  That extra amount movement to tighten them down can move them slightly past their alignment center.  You may need to take into account the amount of travel it takes to tighten down the adjustment bolt into account on smaller dishes.  If it takes a half turn of the bolt to get it tight you may need to stop a half turn and tighten “into” target.  As you tighten it down fully that is where you end up in align.  If you wait until you are in align and then snug it completely down, the force of snugging it down may pull it past and you will end up with a worse signal.

This article sprinkled in some examples from a real-world install, with some theory, with some practical knowledge. Your mileage and experience will vary.  Your experience with 6ghz vs 80ghz will vary as well. Each frequency will have it’s own quirks and tricks.

AIrCube Part 2

Part 1 of our AirCube article can be found here

One of the best features about the new aircube is the interface.  On Facebook and other places the aircube has been criticized for it’s lack of features. I believe this is where the simple interface really makes the unit shine.   One thing many people don’t realize is your typical home router really doesn’t have a true firewall. Most routers have features that are firewall like. Most “firewalls” are security by obscurity.  The ability to close off ports is a by-product of a nat router.

Setup was very easy.  I downloaded the ap, scanned the QR code, and then went into the phones wifi and connected to the AirCube wifi. Once I plugged it into my home router I was online.

One of the first things I always do when testing a new device is upgrade the firmware, unless I have a specific firmware version for whatever reason.  Upgrading the firmware on the unit was very easy.  I like the fact you can see the changelog notes with a single click.

Once upgraded the simplicity of the setup really shines through.  By default, the AirCube is in an access point mode. This is probably the default mode which will be the most beneficial for the ISPs out there.  I will explain why in a little bit.

The interface speaks for itself, I could go through screen by screen and spoon feed you the very simple setup screens, but you would get bored very quickly.  It is truly a very minimalist product and interface.

One of the coolest features I like about this product is the scan feature.  For some reason the way it is presented on screen resonates with me.  It makes seeing the frequencies in use handy.  While not a chart or graph, it still accomplishes the same function.

I know this little product has received some ripping from operators on various groups and forums.  However, I think it fills a very basic need.  That need is an easy to configure device which allows devices to access the Internet.  Nat firewalls can be done by the provider, and the user never has to touch them.  This is a trend many operators are headed toward anyway.  Let the provider manage the endpoint for the customer. The customer ends up calling the ISP to do port forwarding or if they have a virus anyway.  If the customer wants to add things in the house, it should be simple, and not add extra layers of NAT and firewall rules.  This is a perfect fit for the Cube.  So don’t dismiss it because it doesn’t have all the fancy features some router have.  Save that for other product lines that you, as the ISP, can manage.

 

MTIN announces forthcoming 2018 Pricing changes

In an effort to better serve customers MTIN is changing some of our pricing structure. We are moving toward a limited availability structure to guarantee availability to our core customer base while recognizing a one-size-fits-all solution isn’t for everyone.


Tier 1: Customers without a service contract or retainer
$109 per hour during normal business hours (8am-5pm EST time)
$135 per hour for after hours and weekend
First come first serve. No SLA.


Tier II Support
Normal Business Hours (8am-5pm EST time)                           $89 per hour
Late night & Weekend support                                                 $125 per hour
Must Purchase in 5-hour blocks ahead of time to meet response times below for any non-scheduled work.  After hours work can be scheduled ahead of time for normal business hour pricing.

Tier II emergency response times for Tier II customers with a time balance.
Normal working hours (3 hour maximum)
Late night and weekend (4 hour maximum)


Tier III Tech on call Plan
This plan is designed for those who need a high-level engineer on a WISP budget. These slots are extremely limited.

5 hour blocks per week available
6 month minimum commitment
as low as $150 per week paid bi-weekly (1/2 off normal rate)
Discounts are given for multi 5 hour blocks
response times much lower
Contact MTIN for complete details

Contracts available
-Priority support
-Faster response times
-Late night & Weekend support rates don’t apply
-Access to backend monitoring and other services
Contact MTIN on details on contracts

Policy details

1.Late night and Weekend is defined as. 9PM-9AM EST MONDAY-FRIDAY & 8PM EST FRIDAY -9AM Monday. For West coast and customer in other time frames work can be schedule to meet your needs and not be charge for after hours.

2.All customers who don’t have pre-purchased time will be served on a best effort service. Priority will be given to contract customers, and then customers with a balance, and finally to “walk-in” customers.

3.All times stated are maximum times for response. Depending on workload, times are typically much less.

Looking into to 2018

As the snow is melting off during the 50 degree days I have a moment to pause for some of the things coming in 2018.

One of the things we will be working on is some tweaks to our pricing and support structure.  Over the past year, we have been moving to a deeper relationship with our clients.  This helps me provide better support as well add stability to income.  MTIN will be rolling into a more personalized service for clients in the upcoming months.  This will mean more one-on-one attention to clients. With this, we will still be doing “walk-in clients” but only as time allows.   Customers with service contracts and retainer balances will get priority.

Secondly, partnerships with other companies will become a way we will be able to provide customers with a great experience.

 

We look forward to this new year!
Justin

Interesting Mikrotik GUI behavior

While bringing up a BGP session for a client I kept trying to add our side of a /126.  It kept reverting to the network address.  The video shows what happens when I tried to add ::12/126 to the IPV6 addresses.

After some second-guessing and then some Facebook chatting I decided to do a terminal /ipv6 address print.  Sure enough the proper IP shows up.  Must be a GUI bug.

MidWest Co-Location Special

1U Server co-location Special
-1 IP (more based upon justification at additional cost)
-Dual A/B power (dual power or transfer switch capable)
-Multiple transit BGP carriers (HE.NET, Cogent)
-MidWest-IX (www.midwest-ix.com) peering
-Dedicated gigabit port
-10 Megs of burstable bandwidth (more available)
$99 a month
$99 setup fee

Lots of add-ons available. Direct peers to Chicago, FedRamp certified facilities, redundant metro connections, redundant data centers.

Data Center Highlights

  • 99.995% uptime
  • F5 tornado resistant architecture
  • N+N redundant power and cooling
  • Fire suppression and environmental controls
  • Multi-layered security systems
  • Secure workspace for staging, storage and offices

Contact us today for questions and to setup service.

SaaS aka why I should pay per month for billing

The topic of paying per user for a billing or management platforms comes up every so often.  I was able to sit down and talk with several vendors at WISPAPALOOZA this year about the value of their customers paying a per-user fee.

The most prevalent thought is about innovation and new features.  SaaS allows the billing vendor to invest development and testing time in rolling out new features to support new equipment, and other software.  LTE platforms are the hot thing in billing integration. New additions to software take people power and hours of testing and tweaking. Without monthly recurring revenue to drive such things billing vendors would have to develop this and then charge to the early adopters as an add-on.  This can be a double-edged sword. The early adopters have to pay a premium in order to get a partial solution because the vendor has to really prioritize how their development resources are used. The Vendor is always chasing the next big thing, which means other additions or fixes tend to get pushed back. They have to finish add-ons they think more folks will want to buy first.

The next thing is plain old hosting. Hosting a software application, whether in the cloud or on your own hardware costs money.  Co-location, software patches on the OS, hardware lifecycles, etc.  This cuts down on the end-user maintenance side of the hardware but pushes it back to the vendor. The peace of mind of knowing the thing that collects your money is running is backed up, and is available as part of the monthly fee you pay.

SaaS also allows for quicker releases of bugs and new features.  Vendors have more resources dedicated to development and changes. This allows for new add-ons to become available quicker.  Take the traditional model where you get bug fixes, but major feature add-ons are either a full point upgrade or major version upgrade. This usually costs money and is a slower process.  Not only does the vendor have to spend resources advertising, but they have to deal with support and other issues. With billing vendors who charge a monthly fee fixes from companies such as Paypal or Authorize.net are almost always rolled out very quickly at no additional charge to the end user ISP.

Some companies such as Basecamp, which is not a billing platform, have taken a hybrid approach to SaaS. Every major revision that comes out is an upgrade. You can choose to upgrade or stay where you are and pay the same amount.  This can leave customers behind but still allows them to use what they are paying for.  They just don’t get new features or bug fixes.

So the next time you are figuring out why you should pay for a billing platform on a monthly, customer, or subscription basis take all of this into account.

For those looking for xISP billing, and mainly WISP billing, here is a partial list:

www.azotel.com
www.visp.net
www.powercode.com
www.sonar.software
www.splynx.com
www.ispbilling.com (Platypus)
www.freeside.biz
www.quickbooks.com

If you have more please add them in the comments.

Did you know Amazon business account…

Did you know if you have an Amazon business account you can get preferred pricing with some vendors who sell Cambium on Amazon? This is not the same pricing you see when you visit amazon.com.  This is pricing that is extended to you from vendors who sell on Amazon.

The way this works is by passing along your business ID, which is public information, to a seller.  this seller then qualifies you for direct pricing, and if accepted you receive an e-mail saying you have been approved for direct pricing.  When you log in and view the Cambium items the updated pricing is reflected.

MTIN is not the seller of these items, but if you are interested we can pass your Business ID along to some vendors who do.

A story about a rotten company

Recently I received an e-mail from a company I haven’t done business with since 2003. They had kept my e-mail all this time and decided now was the time to send me a spam e-mail.  Let me give you a little backstory on Advanced Internet Technologies Inc.

Back in 2001 I went out on my own as an ISP.  Previously, I had worked for a dial-up ISP and they had been acquired by a larger company.  I saw the writing on the wall and decided now was the time to go out on my own.  With some borrowed money I made my first purchase, a white box 1U server. Keep in mind this is 2001.  This server with a pair of 80 gig hard drives and dual 1GHZ Xeon Pentiums cost me $1800. I had talked to a sales guy from AIT, and liked everything about the company. So I had my little server directly shipped to them and the loaded on Redhat Linux 4.  I was able to cobble my way through setting up sendmail, apache, and some other services and my ISP was up and running in a few weeks.  Things were clicking along for a few years.  We were doing dial-up and had a wholesale agreement with DialUpUSA for nationwide dial-up and ISDN.

Now, here is where it gets good.  One night in 2003 I notice my server load going crazy.  Server load was in the 30’s. Anyone who knows Linux knows this is something bad going on. So as I trying to track down what is going on I lose all connection to my server. No pings, nothing.  So, I call the AIT noc and see if they can look into my server.  I am told they would look at it.   Several hours go by and I am calling and calling trying to get an update.  I had suspected I had been compromised in one way or another and my server was doing bad things. 10PM turns into 10AM.  I call my sales guy at AIT basically pleading for him to find out what is going on.  He answers my phone call once, but subsequent phone calls go unanswered and no one returns my calls.  Still no answers.  I am calling every 15 minutes trying to get someone, anyone to give me answers.  This goes on for a few days.  By this time my business is suffering, because e-mail is down, including my own. After 4 days of no answers, I am in full-blown panic mode.  Luckily I was using the DIALUPUSA radius and e-mail and the web-site were the things down. In the meantime, I find FDC Servers in Chicago which had space and cheap bandwidth.  I rented a dedicated server from them and was able to get things back up and going after a week of downtime.

Fast forward about a month I receive my server in a poorly packed box with a note saying my server had been compromised and had taken down their entire network because it was sending out junk.  At this time on their web-site they were advertising a capacity of 45 megs to the Internet.  That was big time for 2003. And included in this note was an invoice for $2700 for work they had to do in order to deal with my server causing an outage on their network. The next day my attorney was sending them a very strongly worded letter with phone records on my attempts to contact them and how we would be pursuing legal action for violation of their SLA, which did include turn around time for trouble resolution. Many letters and calls later we never heard from AIT again. We were sending certified letters on a weekly basis.  My father would have been proud the amount of legal paperwork we sent to try and generate a response.

Anyway, So now 14 years later I get a SPAM e-mail from Byron Briggs, Chief Operating Officer of Advanced Internet Technologies Inc. on their dedicated server special. They kept my information after all these years, even after one of our letters told them to purge all of my information from their databases.

 

Dear Byron Briggs,
Your company is one of the lousiest companies I have ever done business with. Your total lack of response almost ruined my company. I was a loyal, and on-time paying customer every month of me being an AIT customer.  I still have the original server in my house as a reminder of how awful a company can be.  I feel sorry for the server for even having to be in a data center ran by such uncaring and callous people.  The poor Linux box suffered enough in its life.  I see on your Linked in you have only been at AIT since 2008. It would be easy to say that was in the past. However, Charles Briggs was there during my time as a customer. I am assuming you are one of his four children he speaks of.  I remember talking to Charles on the phone on several occasions when the company was small.  I referred business and we talked about the future of things. The lack of response after all of that was just the nail in the coffin.

Justin Wilson

If you are considering any type of co-location with ait.com I would recommend sticking your server in a refrigerator or cardboard box with a box fan hooked to the local Starbucks wifi before trusting this company with your business.

Oh, and don’t take my word for it
https://www.bbb.org/myrtle-beach/pages/business-reviews/internet-services/advanced-internet-technologies-in-fayetteville-nc-11001845/reviews-and-complaints?noskin&clean

http://www.vistainter.com/reviews/A/ait.com/