Featured post

How to decode Tag-Length-Value Quickly

Basically, in TLV, the format is Tag, Length, and Value. In the list of protocols, TLV is one of the types. Transmitting the data depends on the protocol you used. However, many financial transactions still follow the TLV format.

According to IBM, TLV data is three parts. The tag tells what type of data it is. The length field has a length of the value. The Value field has actual value.


Tag Length Value TLV Ideas to decode Quickly

Structure of TLV.

TLV comprises three field values. 

  1. Tag
  2. Length
  3. Value

EMV formulated different tags. They have their own meanings. Usually, the Tag and Length together takes 1 to 4 bytes.


The Best example for TLV.

In the below example, you can find the sample TAG, LENGTH, and VALUE fields.


[Tag][Value Length][Value] (ex. "9F4005F000F0A001")
where

Tag Name = 9F40

Value Length (in bytes) = 05 

Value (Hex representation of bytes. Example, "F0" – 1-byte) = F000F0A001

In the above message, tag 9F40 has some meaning designed by EMV company. Here you can find a list of EMV Tags.

How to read the TLV

Tag: 1 or 2 bytes

Length: Length of the Value.

F0-00-F0-A0-01  ==> 5 Bytes

The 'F0', for example, is the HEX value of length '1' byte. So the total length of the value '5' bytes.


References

  1. Tag Length Value Wiki Tutorial
  2. List of all EMV Tags

Comments

Post a Comment

Thanks for your message. We will get back you.

Popular posts from this blog

Hyperledger Fabric: 20 Real Interview Questions

Image
I am practicing Hyperledger. This is one of the top listed blockchains. This architecture follows R3 Corda specifications. Sharing the interview questions with you that I have prepared for my interview.

Though Ethereum leads in the real-time applications. The latest Hyperledger version is now ready for production applications. It has now become stable for production applications.
The Hyperledger now backed by IBM. But, it is still an open source. These interview questions help you to read quickly. The below set of interview questions help you like a tutorial on Hyperledger fabric. Hyperledger Fabric Interview Questions1). What are Nodes?
In Hyperledger the communication entities are called Nodes.

2). What are the three different types of Nodes?
- Client Node
- Peer Node
- Order Node
The Client node initiates transactions. The peer node commits the transaction. The order node guarantees the delivery.

3). What is Channel?
A channel in Hyperledger is the subnet of the main blockchain. You c…
Read more

How to Fix Python Syntax Errors Quickly

Image
In Python, you can call parsing errors Syntax errors. How to fix the syntax errors quickly, I can show in this post. Also, check Python Syntax Errors Cheat Sheet.

What is Python Syntax Error?
If you run the Python code, the interpreter first parses the logic. If any errors found, it is the developer's responsibility to fix them.
Courtesy: Python documentation. >>> whileTrueprint('Hello world') File "<stdin>", line 1whileTrueprint('Hello world')^SyntaxError: invalid syntax
How to Fix the Syntax Error?
First, check for the line number. In the above case, it is '1'. Then look for the symbol '^'. The issue is at the PRINT function. The reason is before the PRINT function you need a colon ':'. That is the reason, you are getting error.
This is a syntax error. Find below the corrected logic: >>> whileTrue :print('Hello world') File "<stdin>", line 1whileTrueprint('Hello world')^Syntax…
Read more

7 AWS Interview Questions asked in Infosys, TCS

Image
I have shared 7 amazing AWS interview questions for your quick reference.





1). What is AWS?

Amazon Web Services (AWS) provides on-demand computing resources and services in the cloud, with pay-as-you-go pricing.

For example, you can run a server on AWS that you can log on to, configure, secure, and run just as you would a server that's sitting in front of you

2). What you can do with AWS?

Store public or private data. Host a static website. These websites use client-side technologies (such as HTML, CSS, and JavaScript) to display content that doesn't change frequently. A static website doesn't require server-side technologies (such as PHP and ASP.NET). Host a dynamic website or web app. These websites include classic three-tier applications, with web, application, and database tiers.Support students or online training programs.Process business and scientific data.Handle peak loads. 

3). What is the Security group?

A security group acts as a virtual firewall for your instance t…
Read more