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Using Blockchain, Ultimate Digits Hopes to Disrupt the Mobile Carrier Industry

One of the lesser-understood aspects of the smartphones we use and the mobile carrier accounts to which they’re connected is the fact that a phone’s user does not “own” the phone number to which his or her phone is connected. The number belongs to the carrier and the carrier is leasing that number to the customer. But, between blockchain and the newest breed of phones that support electronic sim cards (aka “eSIMS”), a new opportunity revealed itself to the founders of Ultimate Digits; a company that immutably records the sale of blockchain-based phone numbers onto the Ethereum public distributed ledger.

While at the Outer Edge LA 2023 Conference in Los Angeles, Blockchain Journal technical analyst Bob Reselman sat down with the co-founder and CEO of Ultimate Digits, Atharva Sabnis. According to Sabnis, the impermanence of leased phone numbers isn’t the only insult that smartphone users are currently forced to endure. Mobile carriers have also been caught with their proverbial “hands in the cookie jar” when it comes to the personal data and behaviors of their customers. However, instead of affiliating itself with one of the many global carriers, Ultimate Digits rents telephony infrastructure in bulk and disintermediates the carriers by not only selling phone numbers to its customers in a way that those customers subsequently own the numbers for themselves but also in a way that removes carriers from sitting between those customers and connectivity (thereby preventing carriers from grifting any personal data).

With Ultimate Digits, the entirety of its customer relationships — everything from the sales of phone numbers to billing for wireless services — is recorded on Ethereum, and billings are not only managed via smart contracts, customers can pay with either cryptocurrency or fiat currency.

Outer Edge LA

By Bob Reselman
Published:April 2, 2023

Audio-Only Podcast

Bob Reselman: Hi, I'm Bob Reselman, and I'm reporting to you from Outer Edge 2023 in downtown Los Angeles, California at the Convention Center. So here at Blockchain Journal, we're interviewing Atharva Sabnis of Ultimate Digits. Atharva is the CEO and founder of the company. How are you doing today Atharva?

Atharva Sabnis: I'm great boss Bob, how are you?

Reselman: Hey, I'm great. It's been a great show. A lot of activity going on, a lot of attendees, a lot of vendors, a lot of speakers. So tell me, what does Ultimate Digits do?

Sabnis: Ultimate Digits is a decentralized telecom company where we give people Ethereum blockchain-based phone numbers that are truly owned by them, permanently.

Reselman: So what you're telling me that — right now when I go to my mobile carrier and I bring in my unlocked phone and they give me a sim card with my phone number on it, I don't own that phone number?

Sabnis: No, you're merely renting the number. The carrier owns it, they can cut you off at any time.

Reselman: Oh, really? So you are saying now that you're creating a way where people can own their telephone numbers forever.

Sabnis: Exactly. The number will be truly owned by them permanently. Nobody can take it away from them. They're not forced to change it. Whether or not they're paying their bills, they're using it or not. That is all immaterial. The number will be theirs permanently.

Reselman: So then how do I get my telephone number, my personal own telephone number, how do I get it so that my carrier can use it?

Sabnis: How do you get it so that your carrier can use it? Over here what happens is that — see you are currently renting a number from the carrier. That number is running on the typical cellular infrastructure. That infrastructure is being pledged to particular network operators. When we are decentralizing telephony, what we are doing is that we are renting blocks of telecom infrastructure from various carriers and making those blocks of infrastructure available to a vast set of consumers for them to use as they please. By doing this, we are not locking the consumers to any particular carrier, nor are the carriers getting any consumer data because we are the middle layer in between. So we are renting the infra from them in bulk and we are giving it in smaller chunks to the users based on their requirements.

Reselman: So what you're telling me then is that you, Ultimate Digits are going to say carrier A and saying, okay, I want to buy some of your network infrastructure and you're buying it in bulk and then you're turning around with that network infrastructure and you're reselling it or redistributing it to customers?

Sabnis: Yeah, exactly. So we are buying bandwidth in bulk and then we are giving smaller chunks to users based on their consumption. And by doing this, we are the layer of trust in between. The carrier doesn't require customer data, the customer doesn't have to be billed by them. None of this matters. Ultimately, the customer needs that when they want to make a call, send a text, use data, that service should be available to them and we will make it available to them around the world at all points of time without tying them to any particular carrier.

Reselman: Okay, great. So let me evolve the scenario. All right. So I go out when I go online, I buy an unlocked cell phone now. And I go to you and I go to Ultimate Digits and I get a telephone number. Like 123-456-7890. So I got a telephone number and so I have a cell phone, I have a telephone number. Do I have a SIM card yet? I don't have a SIM card.

Sabnis: So you don't require a SIM card, eSIM is very commonly used. And eSIM is just [an] electronic SIM. All the recent phones support it. So we give you an Ultimate Digits eSIM. And that eSIM is taken by you via a mobile application. So currently if you use T-Mobile for example, with T-Mobile you can already get an eSIM using their app. So we have that same feature so that you can be anywhere in the world. We have no stores, you don't have to come to us, just download the application, get the eSIM installed and ultimately it will show up as your network carrier.

Reselman: So I need to get a modern cell phone. I can't use an old one. I got back in 2019. One that has eSIM.

Sabnis: Yeah, so most of the phones that have come after 2021 have eSIM anyways and typically people change their phone every two and a half years in most geographies. So a lot of people who are currently on the smartphone user base already have phones with support eSIMs.

Reselman: Okay. And just so we have the acronym, what does eSIM stand for?

Sabnis: Just Electronic SIM card, so no physical chip.

Reselman: Oh, an Electronic SIM card. Okay, good. So there's an Electronic SIM card built into the phone. Okay, great. So now we have the phone and I have the phone number and it's wired into a network. So now let's talk about billing. So where does my bill come from?

Sabnis: So traditionally you will get the bill from your network carrier. The bill is computed by them based on the set of rules which they have put in place. In our case, because we are a decentralized telecom company, the bill is actually a smart contract that is on the blockchain which means that the contract is fully transparent. You as a user will know what rules are there. So for a minute of call time per text message, what are the charges? And because it's a blockchain-based smart contract, we are giving people the ability to vote collectively to evolve these rules as the network grows.

Reselman: Oh, great. So the smart contract is smart enough obviously to monitor my usage and also to execute a bill on a periodic basis, say every 30 days. And I received the bill electronically?

Sabnis: Exactly. You can receive the bill electronically, you can pay the bill with cryptocurrency if you'd like or any other currency. And the main thing is that because it's a smart contract, it is an immutable smart contract. So when we want to make edits to the rules, we have to update the smart contract but we don't manipulate the rules. Which means that there will not be billing errors and so forth. So the chances, it's like a[n] idiot-proof bill, it cannot go wrong. The rules are very simple. They're predefined and that is how your bill will be generated.

Reselman: So this could be really transformational to the telecom industry that what this means is I own my phone number, take it with me, and also I could no longer be beholden to a centralized telecom provider.

Sabnis: Yeah, and the other cool factor about this is that, so you know how the U.S. has the +1 country code, India has +91, and every country has a[n] ITU-issued country code. So we have the country code +999 and your 10 digits thereafter follow that +999 country code. Now the cool factor over here is that because it's a decentralized telecommunication system where you truly own the phone number, we let you personalize the number that you want. So if you really wanted 1, 2, 3, 4, 5, 6, 7, 8, 9, 0, if you're early enough to block it, you can get it. And after you have gotten it, it is yours. So you have the ability to even resell it. So tomorrow, if somebody comes and makes a bid that, "Hey Bob, I love your number, can I buy it from you?" With a traditional network, you can't do that. They can just port it, but you don't have any economic gain from that transaction. But in this case, you can just sell the number for a profit if you wish to.

Reselman: So this brings to mind just some security factors because I know — an one time telephone number is just nothing more than making a telephone call. I'd call you and you'd call me. But now with something like two-factor authentication, telephone numbers become really critical in proving identity. How does what you're doing address the security issues?

Sabnis: Yeah, so security is the utmost priority right? So what happens is that the number which we are giving people resides in a crypto wallet that they either already have or we create for them. The number resides in their wallet as an Ethereum NFT. The way it gets tracked is that whichever NFT — whichever wallet holds the NFT, that wallet's owner is the number's owner. Now tomorrow if you sell me your number, the ownership wallet will change. It'll move from your wallet to my wallet. At the time that movement happens, all of these services will be temporarily paused. So you will not get any notifications, selection alerts, so that, I'm not receiving any of your communication[s] by mistake, or your data. And at that point there is a double opt-in wherein you have to go to our app and confirm that you have done the sale. I have to confirm I've received it. And once both of us have given our opt-in, then I will start receiving the notifications which belong to me on that number and you will no longer have access to them.

Reselman: Great. Wow, this is transformational. There's no question about it. It's a really interesting technology. It looks like it's going to be around for a while and it looks like you are at the forefront of making the change.

Sabnis: Hopefully. And the other thing is that what we are hoping to do is that currently, the country code serves as an identifier. So for example, in the U.S., a +1 country code for people who are in the U.S., it doesn't have much significance. Everybody has a +1 country code. People who don't stay in the US, in Southeast Asia, Africa, and stuff. One of the reasons that Google Voice had a[n] early uptake was because they were selling +1 virtual numbers. And people have a value in owning a +1 number because it's an American number. So now with this +999 country code which we are bringing to market, it'll become like a web three or crypto-community country code. So if you and I are exchanging numbers and either of us cites a +999 number then if you know, then we are in that group, you know that I'm in that circle and likewise.

Reselman: Right, it becomes a value add. Well, there you have it. Well, thanks for taking the time to talk to us.

Sabnis: My pleasure, Bob. Thank you so much for talking to me. And yeah, if you have any other questions, happy to answer.

Reselman: Okay, great. And the company is Ultimate Digits.

Sabnis: Ultimate Digits. And you can learn more at ultimatedigits.com.

Reselman: Great, thanks for taking the time. So there you have it, right here from the LA Convention Center at Outer Edge 2023. I'm Bob Reselman and I'm with Blockchain Journal.

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