Transferable Digital Notes Project

Frequently Asked Questions





Can I use TDNs now?
No. This is only a project propossing a technical solution for Central Bank Digital Currency (CBDC). When talking about Digital Currency it is taken as a fact that it is some form of crypto currency, blockchain, distributed ledger or account with the Central Bank. Transferable Digital Notes (TDNs) are not based on any of these technologies. Putting in circulation Digital Currency is a very complex process with legal, social and economic implications. Central Banks all over the world conducted studies to evaluate different technologies for implementing CBDC. As you read this, no central bank has implemented CBDC.
TDNSYS Project is an effort to bring to the attention of financial institution the advantages of using TDNs as a replacement for paper cash.


What is Central Bank Digital Currency (CBDC)
Should be understand that CBDC is mostly an idea or concept and at pressent there is not such currency in existance. According ot Wikipedia:
Central bank digital currency (CBDC, also called digital fiat currency[1] or digital base money[2]) is the digital form of fiat money (a currency established as money by government regulation or law).
Central bank digital currency is different from virtual currency and cryptocurrency, which are not issued by the state and lack the legal tender status declared by the government.[3] As such, public digital currencies could compete with commercial bank deposits and challenge the status quo of the current fractional reserve banking system.[4][5]


Is TDNSYS based on blockchain?
No. Transferable Digital Notes (TDNs) are based on existing, proven database and networking technologies. Paper money as a legal tender is under the control of the Central Bank implying that a Digital replacement for Paper money has also to be under the control of the Central Bank it replicates all the properties of paper cash excluding any distributed technologies like blockchain or distributed ledger.


Can I perform peer to peer (P2P) transactions with TDNs?
Yes. Please see Peer to Peer .


Do I have to be "computer literate" or "computer savvy," in order to use TDNs
No. If you use a TDN enabled bank debit card you don’t have to know anything about TNDs. Please see TDN Smart Cards


Are TDN transactions anonymous?
Please see Please see Security and Privacy


Do I have to use an exchange to convert TDNs to paper money?
No. You can withdraw TDN from your bank account or receive them in exchange for cash at a teller window. They can also be transferred to you as a payment or any other reasons exactly as the cash is.


Do I need a digital wallet?
No. Please see How TDNs are stored and manipulated. for details.


How are TDNs stored?
A TDN can be stored and transferred in the same way as any digital data. It can however be printed and transferred this way. If the string of numbers is printed it is not that useful. Printing it as a barcode makes is possible to be read by any enabled device. here is no exact denomination for a TDN. Any dollars and cents value can be associated with it.
For more information see How are TDNs stored and manipulated


Can I invest in TDNs?
Do not confuse TDNs with Cryptocurrency. TDN is cash. Holding (or hording) TDNs is like keeping paper money under the mattress. It loses value with time due to inflation.


What is double spending?
When you give somebody some paper money obviously you are no longer in the possession of that money. The problem with digital assets is that they can be copied. For example, if a software program is protected with a key it is possible to copy the key and use it again. To prevent this, software companies require software registration. After the registration the key cannot be used again. When using digital tokens as a replacement of money a mechanism must be in place to prevent using the same token again after a payment was made. This problem is called Double Spending.

TDNSYS prevent double spending using a patented method. After receivin a TDN the new holder has to connect to the Central Bank TDNSYS and request ownership of the TDN.

see Get TDN Ownership for details.


What is the TDN Signature?
A TDN Signature is a long string of numbers containing a timestamp, a unique, impossible to guess number and the Dollar value associated with the TDN. TDN and TDN Signature may be used interchangeably.



I don't keep a lot of cash in my wallet, why should I keep money on my digital devices?
Yes, people keep small amounts of cash on hand. Most of the money is deposited in banks and payments are performed using debit and credit cards.

TDNs do not have to be kept on personal devices. You can deposit and withdraw TDNs from your bank accounts exactly as you do with cash with the advantages that you don’t have to go to a branch or ATM (some fees may apply). TDN Apps can automatically make deposits and withdraws as needed for purchases or money transfers. There a also TDN cards for making purchases. Expenses encounters by merchants when accepting these cards are minimal.
For more see TDN Cards, Banking with TDNs,TDN App


How is TDNSYS using cryptography
TDNSYS is not based on cryptography. The only time cryptography is involved is when a TDN is secured with a PKI.
See TDNSYS Security and Privacy for details.


Is the TDN Signature a cryptographic key?
No. Even though it looks like a cryptographic key TDN Signature is just a long, unique string of bytes. The only processing is generating it, storing and retrieving it from the TDNSYS repository and comparison with user input.


TDNSYS is centralized. Isn’t this a 'systemic single point of failure?'
No.This is one of the arguments make by Bitcoin, blockchain and distributed ledger evangelist against centralized systems. These technologies store and process data on multiple computers on the internet. It has to be understood that we are not talking here about data stored on a mobil device or home computer. These are indeed subject to 'single point of failure'.
In a centralized financial system the data is not stored on only one. These systems are implemented using proven technologies used in the Financial Market Infrastructures (FMIs). Data is managed in state of the art datacenters, not some anonymous computers on the internet.


I am already using PayPal to transfer money. Why should I use TDNs?
The advantages of using TDNs is that the parties involved in a transactions to not need accounts and the TDNs ca be used immediately after transfer.


What are tokens and tokenization?
Tokens are digital representations of an asset, good, right, or currency with properties sufficient to attest and transfer ownership.


How are TDNs put in circulation?
TDNs are created by the Fed and distributed through the retail banks in exactly the same way as cash. This process is explained in Issue TDN and Banking.
This posting on the NY Fed describes How Currency Gets into Circulation