Review: AT&T Cell Booster

Back in the mid-2000s I was a huge Apple fanboy, and I really, really, really wanted an iPhone. At that time it was only available from AT&T, and unfortunately the wireless coverage on that network is not very good where I live.

In 2008 a couple of things happened. Apple introduced the iPhone 3G, and AT&T introduced the 3G Microcell.

The 3G Microcell, technically a “femtocell“, is a small device that you can plug into your home network and it will leverage your Internet connection to augment wireless coverage in a small area (i.e. your house). With that I could get an iPhone and it would work at my house.

In February 3G service in the US will cease, and I thought I was going to have to do without a femtocell. Most modern phones support calling over WiFi now, but it just isn’t the same. For example, if I am trying to send an SMS and there is any signal at all from AT&T, my phone will try to use that network instead of the much stronger wireless network in my house. If I disable mobile access altogether, the SMS will send fine but then I can’t get phone calls reliably. (sigh)

I thought I was going to have to just deal with it when AT&T sent me a notice that they were going to replace my 3G Microcell with a new product called a Cell Booster.

Now a lot of people criticize AT&T for a number of good reasons, but lately they’ve really been hitting the whole “customer service” thing out of the park. The Cell Booster currently shows out of stock on their website with a cost of $229, but they sent me one for free.

AT&T Cell Booster Box

In a related story my mother-in-law, who is on our family plan, was using an older Pixel that was going to stop working with the end of 3G service (it was an LTE phone but doesn’t support “HD Voice” which is required to make calls). So AT&T send us a replacement Samsung S9. Pretty cool.

In any case the Cell Booster installation went pretty smoothly. I simply unplugged the existing 3G Microcell and plugged in the new device. The box included the Cell Booster, a GPS sensor, a power supply and an Ethernet cable. No other instructions outside of a QR code which will take you to the appropriate app store to download the necessary application to set it up.

The Booster requires a GPS lock, and they include a little “puck” connected to a fairly long wire that is supposed to allow one to get a signal even when the device is some distance away from a clear line of sight, such as away from windows. I just plugged it in to the back and left it next to the unit and it eventually got a signal, but it is also pretty much beneath a skylight.

In order to provision the Cell Booster you have to launch the mobile app and fill out a few pages of forms, which includes the serial number of the device. It has five lights on the front and while the power light came on immediately, it did take some time for the other lights, including “Internet” to come up. I assumed the Internet light would have turned on as soon as an IP address was assigned, but that wasn’t the case. It took nearly a half and hour for the first four lights to come on, and then another 15 minutes or so for the final “4G LTE” light to illuminate and the unit to start working. Almost immediately I got an SMS from AT&T saying the unit was active.

AT&T Cell Booster Lights

Speaking of IP addresses, I don’t like putting random devices on my LAN so I stuck this on my public network which only has Internet access (no LAN access). I ran nmap against it and there don’t appear to be any ports open. A traffic capture shows traffic between the Cell Booster and a 12.0.0.0 network address owned by AT&T.

I do like the fact that, unlike the 3G Microcell, you do not need to specify the phone number of the handsets that can use the Cell Booster. It claims to support up to 8 at a time, and while I haven’t had anyone over who is both on the AT&T network and also not on my plan, I’m assuming it will work for them as well (I used to have to manually add phone numbers of my guests to allow them to use the 3G device).

The Cell Booster is a rebranded Nokia SS2FII. One could probably buy one outside of AT&T but without being able to provision it I doubt it would work.

So far we’ve been real happy with the Cell Booster. Calls and SMS messages work just fine, if not better than before (I have no objective way to measure it, though, so it might just be bias). If you get one, just remember that it takes a really long time to start up that first time, but after you have all five lights you should be able to forget it’s there.

Review: ProtonMail

I love e-mail. I know for many it is a bane, which has resulted in the rise of “inbox zero” and even the “#noemail” movement, but for me it is a great way to communicate.

I just went and looked, and the oldest e-mail currently in my system is from July of 1996. I used e-mail for over a decade before then, on school Unix systems and on BBS’s, but it wasn’t until the rise of IMAP in the 1990s that I was able to easily keep and move my messages from provider to provider.

That message from 1996 was off of my employer’s system. I didn’t have my own domain until two years later, in 1998, and I believe my friend Ben was the one to host my e-mail at the time.

When I started maintaining OpenNMS in 2002 I had a server at Rackspace that I was able to configure for mail. I believe the SMTP server was postfix but I can’t remember what the IMAP server was. I want to say it was dovecot but that really wasn’t available until later in 2002, so maybe UW IMAP? Cyrus was pretty big at the time but renown for being difficult to set up.

In any case I was always a little concerned about the security of my mail messages. Back then disks were not encrypted and even the mail transport was done in the clear (this was before SSL became ubiquitous), so when OpenNMS grew to the point where we had our own server room, I set up a server for “vanity domains” that anyone in the company could use to host their e-mail and websites, etc. At least I knew the disks were behind a locked door, and now that Ben worked with us he could continue to maintain the mail server, too. (grin)

Back then I tried to get my friends to use encrypted e-mail. Pretty Good Privacy (PGP) was available since the early 1990s, and MIT used to host plugins for Outlook, which at the time was the default e-mail client for most people. But many of them, including the technically minded, didn’t want to be bothered with setting up keys, etc. It wasn’t until later when open source really took off and mail clients like Thunderbird arrived (with the Enigmail plug-in) that encrypted e-mail became more common among my friends.

In 2019 the decision was made to sell the OpenNMS Group, and since I would no longer have control over the company (and its assets) I decided I needed to move my personal domains somewhere else. I really didn’t relish the idea of running my own mail server. Spam management was always a problem, and there were a number of new protocols to help secure e-mail that were kind of a pain to set up.

The default mail hosting option for most people is GMail. Now part of Google Workspace, for a nominal fee you can have Google host your mail, and get some added services as well.

I wasn’t happy with the thought of Google having access to my e-mail, so I looked for options. To me the best one was ProtonMail.

The servers for ProtonMail are hosted in Switzerland, a neutral country not beholden to either US or EU laws. They are privacy focused, with everything stored encrypted at rest and, when possible, encrypted in transport.

They have a free tier option that I used to try out the system. Now, as an “old”, I prefer desktop mail clients. I find them easiest to use and I can also bring all of my mail into one location, and I can move messages from one provider to another. The default way to access ProtonMail is through a web client, like GMail. Unlike GMail, ProtonMail doesn’t offer a way to directly access their services through SMTP or IMAP. Instead you have to install a piece of software called the ProtonMail Bridge that will create an encrypted tunnel between your desktop computer and their servers. You can then configure your desktop mail client to connect to “localhost” on a particular port and it will act as if it were directly connected to the remote mail server.

In my trial there were two shortcomings that immediately impacted me. As a mail power user, I use a lot of nested folders. ProtonMail does not allow you to nest folders. Second, I share some accounts with my spouse (i.e. we have a single Paypal account) and previously I was able to alias e-mail addresses to send to both of our user accounts. ProtonMail does not allow this.

For the latter I think it has to do with the fact that each mail address requires a separate key and their system must not make it easy to use two keys or to share a key. I’m not sure what the issue is with nested folders.

In any case, this wasn’t a huge deal. To overcome the nested folder issue I just added a prefix, i.e. “CORR” for “Correspondence” and “VND” for “Vendor”, to each mailbox, and then you can sort on name. And while we share a few accounts we don’t use them enough that we couldn’t just assign it to a particular user.


UPDATE: It turns out it is now possible to have nested folders, although it doesn’t quite work the way I would expect.

Say I want a folder called “Correspondence” and I want sub-folders for each of the people with whom I exchange e-mail. I tried the following:

So I have a folder named something like “CORR-Bill Gates”, but I’d rather have that nested under a folder entitled “Correspondence”. In my desktop mail client, if I create a folder called “Correspondence” and then drag the “CORR-Bill Gates” folder into it, I get a new folder titled “Correspondence/CORR-Bill Gates” which is not what I want.

However, I can log into the ProtonMail webUI and next to folders there is a little “+” sign.

Add Folder Menu Item
If I click on that I get a dialog that lets me add new folders, as well as to add them to a parent folder.

Add Folder Dialog Box

If I create a “Correspondence” folder with no parent via the webUI and then a “Bill Gates” folder, I can parent the “Bill Gates” folder to “Correspondence” and then the folders will show up and behave as I expect in my desktop e-mail client. Note that you can only nest two levels deep. In other words if I wanted a folder structure like:

Bills -> Taxes -> Federal -> 2021

It would fail to create, but

Bills -> Taxes -> 2021-Federal

will work.


After I was satisfied with ProtonMail, I ended up buying the “Visionary” package. I pay for it in two-year chunks and it runs US$20/month. This gives me ten domains and six users, with up to 50 e-mail aliases.

Domain set up was a breeze. Assuming you have access to your domain registrar (I’m a big fan of Namecheap) all you need to do is follow the little “wizard” that will step you through the DNS entries you need to make to point your domain to ProtonMail’s servers as well as to configure SPF, DKIM and DMARC. Allowing for the DNS to update, it can be done in a few minutes or it may take up to an hour.

I thought there would be a big issue with the 50 alias limit, as I set up separate e-mails for every vendor I use. But it turns out that you only need to have a alias if you want to send e-mail from that address. You can set up a “catch all” address that will take any incoming e-mail that doesn’t expressly match an alias and send it to a particular user. In my case I set up a specific “catchall@” address but it is not required.

You can also set up filters pretty easily. Here is an example of sending all e-mail sent to my “catchall” address to the “Catch All” folder.

require ["include", "environment", "variables", "relational", "comparator-i;ascii-numeric", "spamtest"];
require ["fileinto", "imap4flags"];

# Generated: Do not run this script on spam messages
if allof (environment :matches "vnd.proton.spam-threshold" "*", spamtest :value "ge" :comparator "i;ascii-numeric" "${1}") {
return;
}


/**
* @type and
* @comparator matches
*/
if allof (address :all :comparator "i;unicode-casemap" :matches ["Delivered-To"] "catchall@example.com") {
fileinto "Catch All";
}

I haven’t had the need to do anything more complicated but there are a number of examples you can build on. I had a vendor that kept sending me e-mail even though I had unsubscribed so I set up this filter:

require "reject";


if anyof (address :all :comparator "i;unicode-casemap" :is "From" ["noreply@petproconnect.com"]) {
reject "Please Delete My Account";
}

and, voilà, no more e-mail. I’ve also been happy with the ProtonMail spam detection. While it isn’t perfect it works well enough that I don’t have to deal with spam on a daily basis.

I’m up to five users and eight domains, so the Visionary plan is getting a little resource constrained, but I don’t see myself needing much more in the near future. Since I send a lot of e-mail to those other four users, I love the fact that our correspondence is automatically encrypted since all of the traffic stays on the ProtonMail servers.

As an added bonus, much of the ProtonMail software, including the iOS and Android clients, are available as open source.

While I’m very satisfied with ProtonMail, there have been a couple of negatives. As a high profile pro-privacy service it has been the target of a number of DDOS attacks. I have never experienced this problem but as these kinds of attacks get more sophisticated and more powerful, it is always a possibility. Proton has done a great job at mitigating possible impact and the last big attack was back in 2018.

Another issue is that since ProtonMail is in Switzerland, they are not above Swiss law. In a high profile case a French dissident who used ProtonMail was able to be tracked down via their IP address. Under Swiss law a service provider can be compelled to turn over such information if certain conditions are met. In order to make this more difficult, my ProtonMail subscription includes access to ProtonVPN, an easy to use VPN client that can be used to obfuscate a source IP, even from Proton.

They are also launching a number of services to better compete with GSuite, such as a calendar and ProtonDrive storage. I haven’t started using those yet but I may in the future.

In summary, if you are either tired of hosting your own mail or desire a more secure e-mail solution, I can recommend ProtonMail. I’ve been using it for a little over two years and expect to be using it for years to come.