In my Coinbase account I can see a Bitcoin address which can receive currency, that (I think) gets transferred to my internal coinbase account.
So, AFAIK, without receiving any money, no transactions will appear in the blockchain associated with that RX address.
Finally:
How can an address be found in the blockchain, although it did never send or receive any money?
I think I got my answer.
I was checking my address using blockchair.com .
There, the address showed up with 0 transactions, thus I concluded that it must be present in the blockchain.
Changing a single digit in the address gave me no search results, confirming my conclusion.
The truth is most likely, that the website did some failed integrity check on that address, which yielded in no search results.
So, I think, entering any combination that passes the integrity checks will result in a search entry with no transactions.
That does not mean that the adress is recorded somewhere in the blockchain.
If there is any way to find an address in a blockchain or my understanding is faulty in any other way, please correct me.
Related
not sure if this question belongs here... We are doing a giveaway but we have >30K wallets signed up. We're worried that many are bots. Have you encountered this yet? AND/OR does anyone have a solution to check each wallet transaction history to see if they have any transactions across other signed up wallets? We checked Algo Explorer and it seems that most cases there's a parent wallet and they're sending from the main wallet to a bunch of sub-wallets... thoughts?
Unfortunately there is no good way to prevent this unless you had some form of KYC. I could have a bot create fresh wallets with no transaction history that would be impossible to correlate with each other. Then if those wallets got an asset from you I could then just have them send that asset to the "main" wallet.
You could also set a minimum value of ALGO required to hold in the wallet to be eligible. It wouldn't completely solve the problem, but would make it more expensive for the people operating the bots at least.
Alternatively, set up a centralized service with email + captcha, make each address owner validate their address via that service and deny if they don't.
I am building and app which will offer payment in bitcoins. I know that when I send bitcoin from one address to another it can be tracked by blockain API to verify the transaction. After receiving some assets I want to send some assets back. The customer will have an input field where he will paste his deposit wallet address. I am subscribed to blockchain API to track received assets to my bitcoin address. How can I verify that the payment was made by certain customer? Checking his address doesn't seem to solve the problem because if customer uses wallets like Coinbase, Bitstamp etc. transaction is made from multiple addresses.
A few helpers here:
What you need to do is to generate a new address and give it to your customer. This way you can uniquely identify him
Wait for confirmation before making the decision. Just because you see a transaction, does not mean you have the money. You need to wait for a few blocks and several (>6) confirmations
I need to accept bitcoins on my website (PHP). I'm using blockchain and i have read the api: https://blockchain.info/api/api_receive Is quite simple but i have some questions, but first i will try to explain what i need.
Client send bitcoins to my wallet (Any amount they want)
Server will be notified with confirmations until gets OK.
Gets the sent amount and client wallet from callback and store in DB.
Now my questions:
"You provide a bitcoin address we generate unique addresses that forwards payments to that address instantly notifying a callback URL."
Q: Can we reuse that address and all clients use same address to send bitcoins? Or address will be deleted? The address have a lifetime?
Instead create address to pay is possible clients pay directly to my wallet and server got notified? I don't need extra params like tokens.
I end up in a website that use always the same wallet/address for each odd: http://bitzillions.com/satoshibones
I will like to have a pay system like that, one address per game.
Also should i use blockchain/blockchain (https://github.com/blockchain/api-v1-client-php) library or the simple library (https://github.com/blockchain/receive_payment_php_demo)?
Also if you have any suggestion or alternative i will like to hear.
I think I can help. Disclaimer that I work for BlockTrail.
It would not be good to use the same address because people can view the historical transactions associated with that address. It is recommended to use a new address for every transaction. These can be under the same wallet or different wallets. That may sound complicated but with the possibilities as long as the universe is old you can make a new address per transactions. Some wallets will do this for you automatically. This is called HD Wallets or Hierarchical Deterministic Wallets. You can also use this to have your clients always pay into the same wallet.
You can also use an API to create these wallets. If you are interested in using BlockTrail's here is the link: https://www.blocktrail.com/
We also have webhooks that will send you notifications for confirmations etc... If you want to learn more about our platform, here is a blog that describes it. BTW it is free! https://blog.blocktrail.com/2015/06/blocktrails-developer-platform/
I am trying to create Stripe recipient objects - but no matter what I try I've never been able to get one to come back as "verified." My understanding is that Stripe verifies recipients by checking the name and EIN / SSN fields against a government database. So far as I call tell I'm entering in valid data that should pass the test.
There are no webhooks for validating a recipient - they are either verified immediately upon creating (or updating) a recipient, or they are not verified at all.
Any ideas what might be going on?
Furthermore ... do I even need to verify recipients before making bank transfers? They highly recommend it in the docs - although it's unclear whether it's actually necessary for making a successful transfer.
It takes us a little while to verify EINs on recipients (SSNs are somewhat faster). In the meantime, feel free to send out transfers to these recipients if you're confident they are who they say they are.
Problem Background:
I have a 35K+ user members and growing fast. I am planning to migrate to Amazon SES service. Amazon SES has a criteria to reduce the quota or even terminate service based on bounce-back emails.
I send promotional emails to my members. But the fear is that there are email address which are no longer exists so a fair possibility that Amazon SES notice me and take action to reduce or terminate my service. I need to make sure I have valid email address which do not disturb SES.
Possible Solution:
To cope this problem I am planning to do the following procedure for each email address;
Step1. Collect the MX record for the email domain.
Step2. telnet to that MX domain
Step3. Verify email address with the following pattern
EHLO my_domain_name
MAIL FROM:<my_valid_email#my_domain_name>
RCPT TO:<email_to_verify#my_user_email_domain>
I will verify the response after each command trigger such as email is valid if I receive 250 status after RCPT command
Now what are the possible precautions I should care about to be not marked as SPAM or rejected by the remote server???
I guess you have seen this question here: How to check if an email address exists without sending an email? ? That talks a bit about the disadvantages.
I am no expert but I suspect that it is going to be pretty hard to guarantee that someone won't blacklist you at some point or that you get 100% accurate results from this, or any other method for that matter.
For your scenario though, maybe that does not matter too much - just try to do the check infrequently so that you reduce the number of guaranteed bounce backs and if you send only a few that get bounced back it won't matter too much. On top of that you can have your own system that handles a bounce back and makes sure you do not re-send to that email again.
Doing all of that may be just "good enough" to work.
You may get very different answers from what you expect. Many (most?) e-mail systems set up to prevent spam won't give away user information just like that. My own server, for example, will say 250 OK for every address on my domains, even if those addresses are in fact non-existing.
What you should do is have a system which reads those bounce e-mails and remove unused addresses after a number of bounces. A good way of doing that is having different sender addresses for each message (or at least for each recipient), making it easy to connect bounce messages with their intended recipients. This technique is sometimes called Variable envelope return path.