Podcast: Cameron Kilton from Alpha and I talk about LTE

Cameron Kilton from Alpha Wireless and i sit down at the 2019 Indiana ISP meeting and talk about LTE and Wireless operators.  Pardon the rough beginning. the room we were in had a flickering light that took me by surprise near the beginning and messed with my rhythm.

Cameron’s Twitter
https://twitter.com/cameronkilton

Alpha Wireless
https://alphawireless.com/

CBRSCertified Professional Installer (CPI Package)

This six-module program, developed by Google, will train you to be a Certificated Professional Installer (CPI) of radios which utilize the Citizens Broadband Radio Service (CBRS) band to provide communications infrastructure. Upon completing the course and passing the online certification exam*, you will receive your CPI credentials* and your information will be automatically registered with WInnForum*.

https://www.coursera.org/learn/google-cbrs-cpi-training

ePMP 3000: How to test MU-MIMO

http://community.cambiumnetworks.com/t5/ePMP-3000-MU-MIMO/ePMP-3000-How-to-test-MU-MIMO/m-p/102882

Intial MU-MIMO testing after deployment can be performed through the built-in Wireless Link Test Tool.On Wirless link Test page new option has been added for ePMP3000 – Mode. Wireless Link Test can be started to Single SM or to Dual SMs simultaneously.

ePMP tip of the day

http://community.cambiumnetworks.com/t5/ePMP-FAQ/How-does-the-GPS-Sync-Radio-utilize-the-Active-and-Inactive/m-p/82855#M143

ePMP GPS Sync Radio devices that have an onboard GPS contain two banks of flash memory which each contain a version of software.

The version of software last installed onto the device flash memory (using software upgrade procedures) is configured in the Active Bank. This software will be used by the device when the device is rebooted.

ePMP eDetect

One of the biggest tasks on a wireless AP is finding clean channels.  Once you find those clean channels, making sure you stay on a clean channel is the next task. ePMP has a feature under tools called eDetect. One of the things this can do is give you an idea of how many devices are on a given frequency.

The ePMP AP you see above is on a 20mhz channel, which is why many home routers and other devices are showing up.  If this was on a cleaner frequency it would look like the following.

While eDetect is not a replacement for spectrum analysis, it can give you a pretty good idea of what’s using a particular frequency.  Please note, you see the most things on 20MHZ channels because that is what most home routers are set to. If you would like to read up on eDetect in more detail go here: https://community.cambiumnetworks.com/t5/ePMP-Configuration-Management/ePMP-Tools-eDetect-Explained/td-p/42997

PTp550 Throughput with RF elements horns

Distance:5.03 Miles
Downlink RSSI: -59
ChannelWidth: 40MHZ
DownlinkSNR:33bB
Antennas: RF elements Ultra Horns
Downlink Ratio set to 75/25

Question: Why are you not using channel bonding? 
A)Having some reliability issues with channel bonding at the moment on the 550 platform.

Question: What was the link like before the horns?
Check out this previous post. (pictures are screwed up for now): http://www.mtin.net/blog/the-addition-of-rf-elements-horns-to-a-ptp550-link/

 

 

Transit, peer, upstream. What do they all mean?

As a service provider, you have a mountain of terms to deal with. As you dive into the realm of BGP, you will hear many terms in regards to peers.  Knowing their names AND your definition of them will serve you well.  I emphasized the and in the last sentence because many people have different definitions of what these terms means. This can be due to how long they have been dealing with networks, what they do with them, and other such things.  For example, many content providers use the term transit differently than an ISP.  So, let’s get on to it.

Transit or upstream
This is what you will hear most often.  A transit peer is someone who you go “through” in order to reach the internet.  You transit their network to reach other networks.  Many folks use the term “upstream provider” when talking about someone they buy their internet from.

Downstream
Someone who is “downstream” is someone  you are providing Internet to.  They are “transiting” your network to reach the Internet.  This is typically someone you are selling Internet to.

Peer
This is the term which probably needs the most clarification when communicating with others about how your BGP is setup.  A peer is most often used as a generic term, much like Soda (or pop depending on where you are from). For example someone could say:
“I have a peer setup with my upstream provider who is Cogent.” This is perfectly acceptable when used with the addition of “my upstream provider”.  Peers are often referred to as “neighbors” or “BGP neighbors”.

Local or Private Peer
So what is a local peer? A local peer is a network you are “peering” with and you are only exchanging routes which are their own or their downstream networks.  A local peer usually happens most often at an Internet Exchange (IX) but can happen in common points where networks meet. The most important thing that defines a local peer is you are not using them to reach IP space which is not being advertised form their ASN.   Your peering relationship is just between the two of you. This gets a little muddy when you are peering on an IX, but thats being picky.

I have trained myself to qualify what I mean by a peer when talking about them. I will often say a “transit peer” or a “local peer”. This helps to add a little bit of clarity to what you mean.

Why is this all important? For one, it helps with keeping everyone on the same page when talking about peering.  I had a case a few weeks ago where a Content provider and I wasted configuration time because our definition of transit was different.  Secondly, you want to be able to classify your peers so you can apply different filter rules to them. For example, with a downstream peer you only want to accept the IP space they have shown you which is their own.  That way you are not sending your own transit traffic over their network. This would be bad.  However, if you are accepting full routes from your transit provider, you want your filters to accept much more IP than a downstream provider. So if you have a team being able to be on the same page about peers will help when it comes to writing filters, and how your routers “treat” the peer in terms of access lists, route filters, etc.

Form 477 Resources

https://transition.fcc.gov/Forms/Form477/477inst.pdf
lots of good information in here


https://www.fcc.gov/general/broadband-deployment-data-fcc-form-477

Who Files What?

  • All facilities-based broadband providers are required to file data with the FCC twice a year (Form 477) on where they offer Internet access service at speeds exceeding 200 kbps in at least one direction.
  • Fixed providers file lists of census blocks in which they can or do offer service to at least one location, with additional information about the service.*
  • Mobile providers file maps of their coverage areas for each broadband technology (e.g., EV-DO, HSPA, LTE).  See Mobile Deployment Data.

https://www.fcc.gov/general/form-477-orders-and-releases


https://www.fcc.gov/economics-analytics/industry-analysis-division/form-477-resources/generating-fixed

Generating Fixed Broadband Deployment Data for FCC Form 477


https://geobuffer.com/
Turn US addresses into coordinates.

The Changing RF landscape for WISPs

Recently, there have been some discussions on Facebook about waining support for 2.4GHZ .  KP Performance recently published a Future of 5GHZ and beyond blog post. So why all this focus on 5GHZ and why are people forgetting about 2.4?

To answer this question, we need to update our thinking on the trends in networks, not just wireless networks.  Customers are demanding more and more speed. Network backbones and delivery nodes have to be updated to keep up with this demand. For anything but 802.11 wifi,2.4GHZ can’t keep up with the bandwidth needs.

One of the significant limitations of many 2.4 radios is they use frequency-hopping spread spectrum (FHSS) and/or direct-sequence spread spectrum (DSSS) modulation. Due to 2.4GHZ being older, the chipsets have evolved around these modulation methods because of age.  When you compare 2.4GHZ to 5GHZ radios running OFDM, you start to see a significant difference.  In a nutshell, OFDM allows for higher throughput. If you want to read all about the differences in the protocols here ya go: http://www.answers.com/Q/Difference_between_ofdm_dsss_fhss

Secondly, is the amount of spectrum available.  More spectrum means more channels to use, which translates into a high chance of mitigating interference. This interference can be self-induced or from external sources. To use an analogy, the more rooms a building has, the more simultaneous conversations can happen without noise in 2.4GHZ we only have 3 non-overlapping channels at 20mhz. Remember the part about more and more customers wanting more bandwidth? In the wireless world, one of the ways to increase capacity on your APs is to increase the channel width. Once you increase 2.4 to 30 or 40 MHz, you do not have much room to deal with noise because your available channels have shrunk.

One of the biggest arguments in support of using 2.4GHZ for a WISP environment is the physics.  Lower frequencies penetrate trees and foliage better. As with anything, there is a tradeoff.  As the signal is absorbed, so is the available “air time” for transmission of data.  As the signal travels through stuff, the radios on both sides have to reduce their modulation rates to deal with the loss of signal.  Lower modulation rates mean lower throughput for customers.  This might be fine for customers who have no other choice.  This thinking is not a long term play.

With LTE especially, traditional thinking is being uprooted.  Multiple streams to the customer as well as various paths for the signal due to antenna stacking are allowing radios to penetrate this same foliage just as well as a 2.4 signal, but delivering more bandwidth. These systems are becoming more and more carrier class.  As the internet evolves and becomes more and more critical, ISPs are having to step up their services.  The FCC  says the definition of broadband is at least 25 meg download. A 2.4 radio just can’t keep up in a WISP environment.  I am seeing 10 meg becoming the minimum customers want. Can you get by with smaller packages? Yes, but how long can you maintain that as the customer demand grows?

So what is the answer? Cell sizes are shrinking.  This is helping 2.4 hold on.  The less expensive radios can be deployed to less dense areas and still provide decent speeds to customers.  This same trend allows 5GHZ cells to be deployed as well. With less things to go through, 5GHZ can perform in modern networks at higher modulation rates.  Antenna manufacturers are also spending R&D to get the most out of their 5GHZ antennas. More money in the pipeline means stronger products. My clients are typically deploying 3.65 and 5GHZ on their towers.  LTE is changing RF WISP design and taking the place of 2.4 and 900.