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SMS 10DLC update

Back in March, I posted an article about 10DLC, the new registration mandate for SMS messaging. (see: 10 DLC and short codes: controlling the megaphone).

 In that post, I explored the different options that a business has to reach customers and prospective customers via text, or “SMS” in an A2P (application to phone) manner. Short codes, long codes and TFN (Toll Free Number) services were discussed in the post and the differences were highlighted. The overall theme was that the mobile phone carriers want to know more about WHO is sending WHAT kind bulk messaging to their subscribers. It’s a good thing; I mean, who really wants texts about their auto warranty expiration every day?

 In response to SMS abuse, 10DLC was created as an alternative to the largely unsupervised ‘Long Codes’ (a Long Code is just a standard local text telephone number … like 212.234.1233). Prior to 10DLC, you could obtain these Long Code numbers cheaply, obtain many of them, and blast away. 10DLC changes all of this. And if you’re in possession of some Long Codes, now’s the time to get them registered for 10DLC.

 Although deadlines to register long codes for 10DLC have pushed several times during the pandemic, a hard date of September 30, 2021 has been established for all long codes to be transferred. The good news, is that registering a long code can decrease carrier filtering by up to 90% (providing you remain in good standing, and you’re sending compliant messages that customers want). Missing the deadline could mean heavy filtering by carriers, increased per-message fees and message delivery failures.


To register for 10DLC, you need to initiate the registration by providing the following information to your SMS provider:

  • Employer identification number (EIN)
  • Two contacts
  • Name
  • Email address
  • Phone number


In addition to the above information, there may be questions as to the ‘use case’ for a given 10DLC number (what kind of traffic, about what, to who, etc).  Once you’re registered, you can begin to enjoy largely un-filtered, prompt SMS message sends (providing you don’t try to extend everyone’s auto warranty).


For more information on 10DLC and the SMS A2P landscape, check out this link from Twilio about 10DLC, or feel free to contact us at



10DLC and Short Code SMS : Controlling the megaphone

Of all my inboxes, there’s one I consider, well…. mine.

I have all the normal channels; SMS, email, MS-Teams messaging and Social Media. But among all of these, there’s one that I think of as uniquely mine – that’s my SMS/MMS text messaging inbox. Maybe it’s because my text inbox is inextricably connected to my cellphone number, or maybe because it hosts messages from folks that are close to me. Either way, it is the one single place that I will not tolerate spam. I send STOP replies, I am careful with what services I expose to it, and I expect it to only whistle when I have received a message I want. Apparently, telecom companies feel the same way about it. For some time (in fits and starts) there has been an effort by the large telecoms to better control unwanted SMS messages, blasted at their subscribers.

A2P (Application to Person) type messaging has been available Through several different channels for some time. Let’s review these channels:

Long Codes

Until very recently, anyone could establish a 10 digit standard “Long Code” telephone number (ex 212-222-1357) and write some code to blast out messages. Long codes could be obtained with a low barrier to entry (I.E. no official registration of traffic or user), and acted as though they were P2P (Person to Person) messages. Choke programming was enabled by carriers to scout for mass SMS campaigns that sent messages with the same content to many telephones from Long Codes. Unfortunately, since long codes are cheap ($1/mo per number) and easy to obtain, spammers simply bought tons of them and wrote a routine to ‘round robin’ the traffic across long codes, and stay under the 1 MPS (message-per-second)limit, and other limits of the service. This technique is called “Snowshoeing”. Later this year, long codes will be sunsetted by the telecoms. These numbers will need to be replaced with one of the other A2P channels.

Toll Free Number (TFN)

For some time, an A2P sender has had an alternative in the form of a TFN (Toll Free Number, 800, 888, etc) to circumvent some of the chokes and filters. Use of a TFN requires some level of registration for “high throughput” – up to 200 MPS. Without registration, a TFN is restricted to 3 MPS. Registration of a TFN costs in the neighborhood of $500, and the cost to retain a high throughput TFN can range between  $200-$1500/mo. TFNs are best for ‘steady’ traffic flow.


What if you are a legit company, sending mass SMS traffic that subscribers really want? Is there a way to do it right? Yes, of course there is! Many companies do it today. These companies use the gold standard in A2P SMS messaging: Short Codes.

Short codes have been around since 2006 as a channel allow subscribers to easily send a text an application and initiate an A2P SMS conversation. This channel uses an easy-to-remember short (5 or 6 digit) number. To obtain a short code, companies are required to undergo a detailed registration of the client use case and traffic to be sent. Short codes are a limited resource, exactly because of the short nature of their numbering plan. At either five or six digits, the maximum number of available short codes are as follows:

 5 digit: 10000 to 99999 = 99,999 available numbers

6 digit: 100000 to 999999 = 999,999 available numbers

TOTAL – 1,099,998 Available short-code numbers

So, there is only about 1.1 million in the United States -- they are a scarce commodity. If they were a buck each (like long codes), companies would buy loads of them for everything under the sun. But they are not a buck each. On the contrary, they are thousands of dollars each to setup, and hundreds or thousands a month to retain. They do, however allow a company to send bulk traffic without the telecoms choking and filtering traffic, since their use case is pre-approved and closely monitored.

From this situation, arose the “shared short code”. This was a method where companies would gang up through a service provider and legitimately share a short code. Say someone has a radio commercial, and they are selling the “best plunger ever”. The little plunger company could not afford a dedicated short code, but they found a vendor that farms out a short code, 12345, as shared. They arrange to ask the radio audience to text “PLUNGER” to 12345. Everything’s great, right? Well, it was, until shared short codes were abused by spammers. Say the short code 12345 was vetted, and permission was granted to use it as a shared short code. Then the vendor began selling its use to multiple companies. The plunger app probably would not bother anyone and would indeed constitute a valid use case. But the code’s use was also sold to some other company – and they used it to blast out tons and tons of urgent messages about auto warranties (UGH!).


Because of these developments, the carriers are sunsetting share short codes as a valid use case starting 6/1/2021. Shared short codes will no longer be permissible after that date. Short codes will need to be used by individual organizations, and an in-depth analysis of each use case will be done by the vendor before the code is granted. The carriers will police the use of short-codes via algorithms, and look for abuse. Setting up new individual short codes might cost over $2000 for one-time registration and carrier fees, $1000 per month, and take 2-3 months to provision. Short codes will cost more per-message compared to other channels, depending on carrier fees. Short Codes come with a throughput of 100 MPS and up, depending on a ‘trust score’ that is based on the company size, nature of traffic and other considerations. Short codes are best for clients who do high-volume marketing and mass alerts.


So, some clients have been left orphaned. Clients who used shared short codes to send authentic messaging and reminder traffic can no longer rely on that channel. Others, that used long codes will need to seek an approved, high volume channel that doesn’t come with the price tag of dedicated Short Codes. For this reason, the carriers came up with 10DLC.

10DLC represents a compromise between the largely unsupervised long code of the past and the highly regulated short code. The service uses the old ‘local phone number’ format of long codes (I.E. 212-334-1346). 10DLC numbers are cheap to obtain ($1/number/mo), can be obtained in days rather than months.

10DLC service takes a different approach to registration fees. Registering a ‘brand’ to be used on 10DLC costs $4, but each campaign sent via this number requires an individual registration fee of between $2 and $10. Throughput from between <1 and 10 MPS can be obtained depending on the registration. 10DLC is targeted at companies that wish to conduct transaction messages with a local feel, and with some of the flexibility and cost savings of the old long code.

So the SMS A2P landscape will be changing this year, especially in regard to shared short codes and long codes.

ATI has long been a trusted partner to organizations that wish to use SMS for mass notification and transactional, two way messaging. Reach out to Patrick Bahar ( for more information on how ATI helps clients leverage SMS using the StreamWrite PORTALS platform.






Starlink: New stars in the sky

Last November, British stargazers were surprised to see something in the night skies that seemed, well, alien. A long line of starlike points crossed the sky, seeming to follow one another. Some amateur astronomers may have been ready to contact SETI, but most knew exactly what they were.


In another bold move by Elon Musk, Spacex has stepped up the delivery of tiny LEO (Low Earth Orbit) satellites poised to bring affordable high-speed network access to the entire globe. With 60 micro-satellites per Falcon 9 rocket launch, there are 961 spread across 72 orbital planes as of January, 2021. In the future, up to 400 satellites will be lobbed into orbit on a single Spacex Starship rocket. The lofty goal of StarLink is affordable high-speed internet and IOT links to every point on the globe.

Spacex’s ambitions are not without controversy. Astronomers and amateur stargazers contend that the massive constellation of artificial objects will obstruct the clear view of the night sky, and even potentially set back research in Astro-Science. They are concerned that 12,000 potential ‘false stars’ will clutter up research viewing for generations to come.

On the other side of the coin, Starlink has the potential of bringing the Internet to places and people that have been denied it in the past – particularly in the third world. Starlink will enable remote monitoring of IOT devices in places that previously had no cell or internet coverage. With the current constellation, price and speed are somewhat underwhelming, compared to terrestrial alternatives. At $99/mo (and $499 on-time cost for small dish and gear), and speeds of 100 to 150Mbps, Starlink doesn’t scream – but that will change. As the constellation grows, so will speed. Starlink is already testing some pretty cool stuff – like satellite-to-satellite laser based communication that will allow packet to ‘jump’ between satellites, negating the need to bounce back to earth and up to another satellite before reaching the user. Latency reports have been pretty good for a satellite based system, at 20 to 40ms. LEO shortens the height to around 800mi altitude, compared Geo-synchronous solutions of the past that sit WAY up at over 22,000 miles. Even with signals moving at the speed of light, this dramatically reduces the propagation delay and latency.

The aforementioned Laser based, satellite-to-satellite connection will be a boon for folks in the extreme northern and southern latitudes, as the Starlink satellites that will be loft into a polar orbit will not have ground stations to relay. Once Starlink is fully deployed, these sparsely covered areas will now have access to the same internet access that the lower latitudes have enjoyed, helping remote research stations to stay connected.

Starlink is just starting, but when the full constellation is ready, users will have one more reliable alternative to cable, fiber, geo-synch satellites and fixed-mobile internet. It will be interesting to watch this new service unfold.

Business Reply Mail - By SMS Text!

Junk mail. We all get it, we all chuck it. But every now and there, there's something we reply to. C'mon, admit it. You've returned one of the envelopes, tear-off cards or or stuffers at some time. As a marketer, these little scraps of paper can be gold - a way to get contact info back from a perspective customer. Magazine tear-outs, utility bills and weekly circulars all have alive-and-well business reply models working every day. Why is something so decidedly low tech still viable? Familiarity, I think. We know this to be an effective, if not slow, means of expressing interest in an offering. What modern medium might a marketer combine with this approach?

How about SMS Text?

The more common means of interaction between individuals and increasingly with companies is SMS Text. People are comfortable with it, and it's just as familiar as the little scraps of paper. Add a line in an existing campaign that says something like 'return the card below, or text OFFER12 to 55453'. Now you have instant access to a new customer. You can start an interaction that asks the customer's name, when best to contact them, offer web links to products and purchase portals. It's that little card on steroids!

Streamwrite has a comprehensive suite of customer interaction and notification systems that leverage SMS Text, email, conferencing, call routing and outbound calling. 

Check us out, and we promise not to send you any sea monkeys!


Hacker. The word prompts images of energy-drink guzzling teens breaking into databases and stealing personal information. But that's really not right.

A real hacker, in the tradition of Woz, Captain Crunch and other OG hackers wasn't at all about stealing. It was about solving a puzzle, playing a prank, showing your smarts.

Hacking really didn't start out with computers. During the 70s and early 80s, it was pretty hard to get a hold of the necessary hardware to do computer hacking (a teletype, a modem, $1000 of 70s dollars). Early hackers were 'Phone Phreaks', folks that used home-brewed gadgets like 'Blue Boxes' to create MF tones. These tones could be used to re-direct a call intended for a toll free service, to any number in the world with no charge. Hackers would do funny things like create a phone call that circled the globe on analog trunks, and marvel at the 10 second propagation delay when the spoke in one phone and listened on the other. As services like compuserve, AOL and TYMNET gave way to the Internet, these same clever souls refocused their  antics on systems they could access with microcomputers. The modern hacker was born.

The truly remarkable hacks, or 'Pranks' usually spawned from academic institutions, and more often than not, CalTech and MIT. A playful rivalry between these tech giants had gone on for decades. One in particular, is my favorite -- because of it's complexity, playfulness, and attack on college football, which in my opinion, takes itself way to seriously. 

The 1984 Rose Bowl took place on a warm and sunny January 2nd, between The UCLA Bruins and the University of Illinois Fighting Illini. Little did the fans, Tournament officials or Rose Bowl staff know that months before, a small team of CalTech students had made several unauthorized visits to the Bowl grounds. First, they gained access to the pressbox, and 'borrowed' manuals on the PDP-8 computer and the scoreboard software that controlled the huge electronic scoreboard above the stadium. Using those manuals, they reverse engineered the serial interface that was transmitted from the PDP-8 to the scoreboard. Later, they engineered hardware that could be tapped into the serial connection, and inject messages to the scoreboard. 

Like Ninjas, the team went back on night, and using rock-climbing skills they accessed a junction box under the pressbox where the serial cables connected. They installed a hand-modified microcomputer (think mid-80s) with a serial interface connected to the line. They used a walkie-talkie acting as a modem connection, allowing them to control the clandestine microcomputer from a nearby hill. 

Back on game day, during the 4th quarter the team sent some packets down their radio interface that changed the team names from UCLA and Illinois to CALTECH and MIT. They left other important game stats unchanged, like the score, but made sure that UCLA score of 38 was assigned to CALTECH, while Illinois' paltry 9 points was assigned to MIT. 

The tournament officials were outraged, and leveraged the Pasadena police and the City Prosecutor to press misdemeanor charges against two of the Caltech students, Ted Williams and Dan Kegel. There was outrage in the press and with the public, which loved the prank and were solidly behind Caltech.  This ended up with the students pleading "nolo contendre'', and serving probation and with no entries into their records. 

What I love about this story is the sheer audacity of attempting something like this. It reminds me of the brilliant hardware and software engineers I've had the pleasure of working with throughout my career. 

I feel so lucky to be working at a company filled with engineers who think like Williams and Kegel. 

Prank on!