Full LTE Architecture explanation

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Justin’s List of xISP vendors and resources

I have been working on this list for a while. The following are vendors, manufacturers, and various companies I have dealt with in my career as an ISP owner and consultant. This is not a complete list by any means. These are companies I have dealt with personally and/or are sponsors of this site. Companies with the are ones that support this blog and I personally recommend.  I don’t recommend them just because they support this blog, but because they provide a good product or service. If you would like to be included on this list please contact me as I am working on more detailed lists per category.  This is a starting point for those looking to narrow down some focus of their research.

ISP Supplies
Texas-based distributor carrying a big number of product lines such as Cambium, Mikrotik, Airspan, and many others

Baltic Networks
Chicagoland based distributor carrying product lines such as Mikrotik, Cambium, and others.

Distributor of fixed wireless and telecommunications infrastructure for Internet Service Providers (ISP’s), Cable Operators, Telephone Companies

Double Radius

Mature billing solution which can
manage all aspects of your ISP.

Modern Billing software with many backend automation

Automation and control of your WISP customers

More Billing providers can be found at xISP billing platforms

LTE and CBRS based solutions

Cambium Networks
Manufacturer of fixed wireless products such as EMP, 450, and cnPilot wireless.

Manufacturer of Mikrotik routers and RouterOS routing and switching products

Manufacturer of WISP and WIFI products. Product lines include AirFiber and Unifi.

Tower Related
Training and equipment to keep climbers and companies compliant and safe. Large selection of needed items such as Harnesses and rope related items for tower work.

Unified communications with experts to help you migrate and stay compliant. Here is a link to a podcast I did with Ateral.

True IP Solutions
Unified communications solutions integrated
with access and camera solutions.

Rick Frey
mikrotik training and certification as well
as consulting and integrations solutions

Training on Mikrotik and distributor of related products

More info on training for the xISP 

Supporting Services
RF Mapping and Modeling for tower sites and customer pre-qualification

Wireless Mapping
Radio Mapping, two-way radio, mark study information, and Municipal broadband.

Microwave and Millimeter Wavechannel procurement.

Organizations, web-sites, and groups
Trade Organization supporting Wireless Internet Service Providers=

WISP Talk on Facebook

Cambium Users group on Facebook

YouTube Channels 
Networking, ISP, and related topics


Did I forget you? Would you like to sponsor this blog and your name listed? Contact me for more information.

WIFI calling port forwarding

Recently I came across a need to do some port forwarding for wifi calling. I have assembled a resource guide to help you if you need to do such things. IPSEC should be allowed per RFC 5996 https://tools.ietf.org/html/rfc5996 for all wifi calling

UDP ports 500 and 4500 open to sg.vzwfemto.com and wo.vzwwo.com

IPv4 Address Block: and
UDP Ports 500 and 4500
5061 for SIP/TLS
TCP port 443 and 993
Also whitelist the CRL server for DIGITS OTT and WFC 1.0: crl.t-mobile.com

UDP Ports 500 and 4500
TCP Port 143

Whitelist the following:

  • epdg.epc.att.net
  • sentitlement2.mobile.att.net
  • vvm.mobile.att.net

UDP Ports 500 and 4500

Any of the above is subject to change.

OpenVPN, rooter project, and Mikrotik

Over the past couple of weeks, I have been fighting with getting an LTE device running The Rooter Project to establish an OpenVPN connection with a Mikrotik router. Apparently, OPENVPN is the only option when it comes to VPNs on The Rooter Project. For the purpose of this article, I am going to refer to the software as “the rooter”. This is just to denote the device running The Rooter Project software. In my case, this is a GL.iNET GL-X750 LTE device.

There are two parts to this setup. The OpenVPN setup on the Mikrotik and the setup on the rooter.

Mikrotik Setup

The Mikrotik setup is pretty straight forward. There are some great tutorials out there for a more in-depth setup. The RouterOS version I used for this setup is 6.47.

Creating Certificates
You will need to create 3 certificates on the Mikrotik.
1. cert_export_ca-certificate.crt

add name=ca-template common-name=example.com days-valid=3650 key-size=2048 key-usage=crl-sign,key-cert-sign
add name=server-template common-name=*.example.com days-valid=3650 key-size=2048 key-usage=digital-signature,key-encipherment,tls-server
add name=client-template common-name=client.example.com days-valid=3650 key-size=2048 key-usage=tls-client

Signing Certificates
Once you have created the above certificates you will need to sign them with the following

sign ca-template name=ca-certificate
sign server-template name=server-certificate ca=ca-certificate
sign client-template name=client-certificate ca=ca-certificate

Exporting Certificates
Run the following commands to add a passphrase to your key certificate and export them to files

export-certificate ca-certificate export-passphrase=""
export-certificate client-certificate export-passphrase=j2sw123com

This will give you three files: cert_export_ca-certificate.crtcert_export_client-certificate.crt, and cert_export_client-certificate.key. Download these out of “files” from the Mikrotik to the same computer you have access to the rooter on. I like to rename them to ca.crtclient.crt, and client.key so I can keep track of what is what.

Rooter Client Setup

I could not find out how to make the operating system read a config file I would edit by hand. Even after a reboot, the config file would not be read. I am not sure if there is a command to read it into the running-config. If someone knows, let me know and that will make this process much easier.

dev tun
proto tcp
remote example.com 1194
resolv-retry infinite
ca ca.crt
cert client.crt
key client.key
remote-cert-tls server
cipher AES-128-CBC
auth SHA1
redirect-gateway def1
verb 3

In my rooter, the config is in /var/etc. I would cat this occasionally to make sure I did not have any extra options turned on. Since I could not make my edits the file stick, I would make the below changes in the GUI and verify they matched up to my above file.

If your OpenVPN is using a username and password create a file named passowrd.txt and put the username on the first line and the password on the second.

You will need that file along with the three files you generate on the Mikrotik above.

Log in to the router and create you an open VPN instance. In my case, I named it Nexstream because this is who I was working for on this project. You can name it anything you want.

Click on edit and you will be brought to the following screens. Fill them out as shown.

When you get to the bottom this is where you upload your password.text and your cert and key files. If you see anything missing go to the bottom and select the field and click add.

Make sure to hit save and apply before proceeding. Click on “switch to advanced configuration”. Match up your configuration with the following screenshots, which match up with the above config file. You are just basically making the proper checkboxes to match the plain text config I posted above. Again, if anyone knows how to get OpenVPN. on the rooter to read the config in let me know.

Once you have the GUI part done and the certs uploaded to the rooter you will need to deal with the keyphrase via the command line. Simply SSH to the rooter. The below code is a generic code for changing the client.key to not ask for a passphrase anymore.

cd /etc/luci-uploads/
openssl.exe rsa -in client.key -out client.key
Enter pass phrase for client.key: j2sw123com
writing RSA key

Couple of things to note about the process.
1. Your location may vary. You must either be inside the directory with your keys or provide the path to the keys in the OpenSSL command

2.when I uploaded the keys it changed them to cbid.openvpn.FRIENDLYNAME.key.

what my actual code looked like to change the passphrase

cd /etc/luci-uploads/
openssl.exe rsa -in cbid.openvpn.vpnout.key -out cbid.openvpn.vpnout.key
Enter pass phrase for client.key: j2sw123com
writing RSA key

If everything goes well you will be rewarded with the following screen on your OpenVPN main page. If, for some reason, it does not start the system log is actually pretty informative on what is going on.

Some Mikrotik SXT photos and first thoughts.

I have been wanting to do some photos and thoughts on the Mikrotik SXTR-LTEs and other Mikrotik LTE products. I recently fired one up using dual sims. One is from Tmobile and one is from At&T.  Verizon is pretty nonexistent in my area. I am about 2.5 miles away from a Tmobile tower and about a mile from a fiber-fed AT&T monopole.

As you notice in the following photo I am pretty buried in trees.

My view of the tower. Notice the high-tech holder.

Some initial notes.  Setup of LTE is a very easy process as far as the mikrotik is concerned.  I literally had to put in some information in the APN and that was it as far as LTE goes.  I did set up standard Mikrotik stuff (DHCP server, security, etc.).

Adding the second sim card can be a huge pain due to the location of the sim card slot.  Luckily I had some tweezers that were angled to be able to slide the card in the slot.  These were part of a dental kit I picked up off Amazon for releasing stuck SFPs and the like.

Look for a more in-depth series on Mikrotik LTE coming soon.