Registration – How to block multiple logins / Register?

So, I have an application where the user needs to register to access the application.
I am planning to run an offer where the user can order that item only once a day.
But I have the doubt that he can change the login ID (if he has several emails) and can place the order with different IDs.

I am thinking of registering the device with an email ID:

– You cannot log in with a different email ID.

– The application cannot be used on a different device (if it is changed), since it can give an error email ID already registered on another device, which leads to canceling the registration of the previous device (it is possible that the device not available). It takes a long time. This can lead to loss of customers.

Also, read about the IP tracking, phone number and credit card details, but you are not satisfied with the answers (someone has already raised the same thing).
So what will be a good method to avoid multiple logins / registration from the same device?

What is the complete process and purpose of a block validation using merkle trees?

I need all the details please. How does that happen only in the current block? Or in past blocks? And how exactly does this happen? Do the complete nodes send the appropriate hashes and then a local light node calculates them until it reaches the merkle root?

An example with an explanation of the step by step process would be ideal. I need all the technical details described as simple as possible

Can a firewall recognize (and block) outbound traffic consisting of screenshots?

I recently watched this YouTube video about capturing webcam image traffic using Wireshark. Although the technique used in the video is not applicable to my question (because it is a MITM situation), it shows how image data, such as webcams, is sent over a network.

What interests me most is to block screenshots taken by malware and similar code.

Is it feasible to have a hardware firewall device to monitor data packets and remove packages that contain images, or is this type of low-level analysis usually too demanding for consumer-level devices?

magento2 – Magento 2 custom product block on the cms page

I want to show a custom product block on the cms page. Then I created


then in

myphpcode.phtml I write the following code

 $productId = "1141"; //Product Id

 $objectManager = MagentoFrameworkAppObjectManager::getInstance();
 $product =
 echo $product->getName();

and on the cms page I write the following code

{{block class="MagentoFrameworkViewElementTemplate" template="Magento_Theme::myphp/myphpcode.phtml"}}

now i can get the product name . But I want to get the complete product block. I like how a product in the category page or search page, etc.

Why am I doing this? I have 3.4 product ID. I have to show these products on the cms page. If this product is in the same category, then I can do this as insert widget with category ID. But is not.

So I want to show the entire product block in pages

How do the different block chains communicate?

I learned that different cryptocurrencies have their own P2P blockchain networks.

How do you exchange currencies from one network to currencies in another network?

What happens when the last block added in a blockchain is damaged?

Each complete node unilaterally verifies the validity of each block. When a block does not adhere to the consensus rules, a complete node will not accept it as valid, will not consider the transactions included as confirmed and will not forward it to other nodes.

A similar incident occurred, for example, in July when Antminer accidentally claimed a block reward higher than the one allowed in block 584.802.

You can read about that a little more for example here:

Why is a custom block with a form not represented in a Bootstrap theme?

In a bootstrap subtopic, my blocks with embedded forms are not processed. I verified that even if I enable only the base theme, the problems still persist. Any idea on why the blocks with embedded forms will not be displayed in a boot subtopic Instead, I left and started building my own theme from scratch, after trying to debug it for a long time.

blockchain: how do block explorer sites show information that is not available in Bitcoin Core?

How can you list unused transactions and the current amount of an address that is "not in your wallet"?

Block explorer sites maintain a separate database of information that is built by continuously scanning the Bitcoin blockchain. If the block browser sites see a standard blocking script on transaction exits, they remove the addresses of those blocking scripts and the amount associated with that exit. This information is added to your database. Also, when a user spends bitcoins, they must refer txid and the output index at the transaction entry. Block explorer sites use this information to locate that exit and verify the exit blocking script, from which they derive the & # 39; input address & # 39 ;. All this information and continuous searches allow block explorer sites to associate funds with addresses and show whether bitcoins sent from a transaction have been spent or not. However, if you block a transaction in a custom script, block browser sites cannot decode this information.

How can they have information on this new generated address?

They continually scan the blockchain from which they can obtain transactions included in blocks. In addition, block browser sites run full nodes that help them collect transactions transmitted by other nodes in the mempool that have not yet been confirmed in blocks.

How can I block the use of the YouTube application and the YouTube website in all browsers on the iPhone 5s?

My 10 year old son is using YouTube every day for 5-6 hours on his iPhone 5s.

Is it possible to block the use of the YouTube application and access so you don't lose your childhood?

If possible, is it possible to unlock it again for a while, when I want to let YouTube use for 2-3 hours on Fridays and Saturdays and then block it again?

There is a YouTube application installed on the phone and also Safari and Chrome browsers.

How to unlock my MS block IP


As I mentioned elsewhere in the webhostingtalk forums, some of my clients do not maintain their websites, which sometimes results in the sending of unwanted emails to accounts that do not exist worldwide.

The biggest problem and so far not resolved for me is the next block of my IP address when sending messages to email accounts managed by Microsoft (not only but also includes, and all the domains that use the MS email services) as a result of these Spams

So, the emails from my blocked IP to MS email accounts look like this:

———— Start ———- host ( said: 550 5.7.1
Unfortunately, no messages were sent from ( Please contact
your Internet service provider since part of your network is in our block
list (S3150). You can also refer your provider to
( (in response to MAIL
DE command)

———— final ———-

The link above ( It only describes the reason, it also refers to spamhouse but my blocked IP does not appear in spamhouse, therefore I cannot unlock.


How can I eliminate this type of IP blocking (when the problem with spam is eliminated)?