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Welcome To Cyber Aeronautycs Ltd.


We are an aerospace and defense company in Bangladesh and engaged in research, design , development, manufacture, integration and sustainment of advanced technology systems, products and services.

CAL Secure Notary Cloud

Notarization Service

Allows customers to notarize files of any type via a web console or API, generating a certificate that provides publicly verifiable proof of its timestamp, integrity, and authenticity.

E-signature Service

Customers and required parties can electronically sign documents while generating publicly verifiable proof of the timestamp and integrity of signatures.

Verification Service

After the signed document or file is notarized, customers can verify it from any device, at any time, directly from the solutions’s user-interface or manually through the blockchain ledger.

Provide confidence that business data is authentic

CAL Secure Notary Cloud is a blockchain-based service for file notarization, e-signing and verification for businesses of any size. Designed exclusively for service providers, it allows your customers to ensure the integrity of their business-critical data, while achieving regulatory transparency and decreasing security risks.

  • Differentiate your business - Boost your data protection business with an innovative portfolio offering
  • Sell, upsell or bundle with ease - Deliver a universal service that fits businesses of any size, in any industry
  • Leverage blockchain technology - Add extra layer of data protection that removes any risk of fraud

Key Features

Ethereum Blockchain

Cyber Notary Cloud leverages the fast-performing Ethereum blockchain, whose distributed architecture ensures verification is always available, and there is no possibility for fraud or interference.

Custom White-Labelling

CAL Secure Notary Cloud provides an ability to white-label the interface. Customize the name of the service, it’s logo, URLs, color scheme, email design and more.

Independent Verification

Verify notarized files either through the built-in interface or via public sources. As long as there’s access to the blockchain, anyone can check from any device at any time.

Embeddable e-signatures

Easily execute every step of the document workflow – from creation, to sending the document to multiple signees – with an easy drag, drop, and sign feature.

Smooth Integration via API

CAL Secure Notary Cloud’s API enables tight integration with any application, with the ability to tie the service’s backend into a user interface.

Easy-to-use web interface

Equipped with a ready-to-use, intuitive web interface, CAL Secure Notary Cloud provides quick onboarding and a high level of usability for the end users.


Blockchain Data Authentication


Simply put, it is a distributed database that maintains a continuously growing list, or chain, of data transaction records. Every portion of this decentralized system has a copy of the chain – so no single, “official” copy exists. The distributed nature of the chain prevents tampering and revision, which makes it easy to confirm the authenticity and security of every transaction recorded on the chain.

Data “Fingerprints”

CAL Notary computes a cryptographic hash, or “fingerprint”, that is unique for each file. This hash is an algorithm that produces the same output when given the exact same input file, making it useful for verifying the file’s authenticity. Any change in the input file, however slight, results in a dramatically different fingerprint. Because the hash algorithm is designed to work only in one direction, it is impossible to determine the original file inputs from the output alone – making the process tamper-proof.

Anchoring data in the Blockchain

Think of the blockchain as an “append-only” ledger with a transaction order that is distributed across many entities, with each entity keeping an identical copy of the ledger. Every record in the ledger is time-stamped, immutable, and independently verifiable.

A hash of the whole structure containing the files’ fingerprints is recorded into the blockchain. The authenticity of those files can be independently confirmed by any party (even one not doing business with us) that has access to the blockchain.

How can CAL Secured Notary be used, and why should you care?

CAL Notary adds an extra level of confidence to the authenticity of your personal and business data. In the future, you may want to simply reassure yourself that a file you previously stored or backed up has remained unchanged since then. Or you may have a file (or someone may present you with a file) that you need to validate, confirming it is authentic and unchanged from its backup. While we share some use cases below, common potential uses include property records, court documents, and long-term archives that could be subject to legal or tax audits.

Provide confidence that data is authentic and unchanged.

Example and use cases

Prove that a document is unchanged or changed
  • Suppose you have an executed agreement that is backed up to local storage or the Cloud. The other party to the agreement also receives a digital copy of the exact same document. In a few months, you get a call from the other party telling you that you didn’t fulfill the contract. That party shows you a document that seems to be original. But you suspect they made some changes to it.

  • Using CAL Notary technology, you compare a certificate you generated for this “new” document with the original document’s certificate. That way, you can be sure that the recent document is an identical bit-for-bit match to the one you have in backup storage. If they don’t match, you know that the other party has changed the document in some way and can confirm what they have is not the original document.

Confirm a creative work originated in a certain date
  • A visual or musical artist may be skeptical about publishing creative assets on the internet. Using CAL Notary certification — a tool for copyright protection that can help confirm the date of origin — can change his mind.

  • To do this, the artist creates a backup that contains pieces of digital art, music, photos, or anything else that can be copyrighted. Once the backup is complete, he can obtain a certificate with cryptographic evidence that could help his copyright claim in case of infringement. The record of the original pieces and their creation dates are recorded in the blockchain. Artist can confirm that his piece of art existed at a certain time in the past, was authored by him and assist his copyright claims.

Prove a legal document existed when you claim it did

  • Lawyers may need to prove to a judge and jury that a file in their possession has been in existence since a certain date and time. Using CAL Notary, they can tie the file in their possession to data on the blockchain, which mathematically proves the existence of that exact file at the specific, earlier date in question.
Confirm bills were paid when you said they were paid

A company keeps an archive of all of its old, paid invoices in a notarized backup. One day, the company receives a letter demanding payment for an invoice that was paid two years ago. The record in the blockchain is permanent and immutable, so the company can confirm that this invoice was re-sent by mistake.

Confirm product certificate is unchanged

A consumer buys a certified diamond with an associated serial number on it. He backs up the diamond’s “warranty of authenticity” and proof of purchase with CAL Notary. After some time, he decides to sell the diamond. A prospective buyer can use CAL Notary to verify that the diamond’s purchase records are unchanged, so he can confidently move forward with a third-party’s professional gemstone evaluation.

If we are talking about an individual user’s

documents, these are examples of what

they may need to sign and notarize:

  • Rental/lease agreements
  • Sales contracts or asset purchase agreements
  • Loan agreements
  • Permission slips
  • Financial documents
  • Insurance documents
  • Liability waivers
  • Healthcare documents
  • Research papers
  • Certificates of product authenticity
  • Nondisclosure agreements
  • Offer letters
  • Confidentiality agreements
  • Independent contractor agreements


What is blockchain?

Blockchain is a technology based on the principle of a continuously growing list of data records, or blocks, which are linked and secured using cryptography. Each block contains a cryptographic hash of the previous block, including a timestamp and transaction data.

Most people know the term “blockchain” because it is used as the basis for cryptocurrencies like Bitcoin or Ether. But the underlying concept allows blockchain technology to have a variety of use-cases, such as file notarization, digital voting, creating smart contracts, and more.

The key advantages of the technology includes:

Security: Blockchain uses strong cryptography to create transactions that are impervious to fraud.

Distributed architecture: Blockchain leger is not owned by anyone as it can be distributed across multiple organizations and becomes more secure as replicas are added.

Impossible to backdate changes: Every transaction is written into the ledger once and cannot be changed thereafter.

What is blockchain-based data notarization?

Blockchain-based services for data notarization allows to notarize business critical data of any type automatically by creating a digital fingerprint for files and storing it in a public blockchain ledger. It empowers companies with independent validation of data authenticity and proof it existed at a specified date and time.

What is blockchain as a Service?

Blockchain as a Service (BaaS) is based on the Software as a Service (SaaS) model. This approach allows customers to access and leverage blockchain-based applications, while a cloud-based service provider manages all activities required to keep the infrastructure up and running.

How does e-signature work?

An electronic signature, or e-signature, is the software that links a signature to the signer’s identity and intent to sign to the time the document was signed. E-signatures streamline the document approval process by enabling online signatures with a click of the mouse or by using touch pad.

To sign a document with CAL Secured Notary Cloud you will need to:

  • Select the desired file by browsing, or drag and drop it
  • Specify the signees by entering their email addresses
  • Ensure all participants review and digitally sign the file
  • Once all signatures are received, you can get signature and notarization certificates, which are publicly verifiable proof of the timestamp and integrity of e-signatures

How to purchase ? Please contact us via chat or the contact form


01832 644442 (Whatsapp and Call)


Level 4, Awal Center, 34, Kamal Ataturk Avenue, Banani , Dhaka-1213,Bangladesh


Aerospace & Defense Company

Our Industry


National Security




Information Technology

Financial Services


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Registered in Bangladesh . Company Registration Number C-172611