As everyone will know by now, in the last year, the explosion of NFTs has dominated the crypto and blockchain market with projects that have sprung up like mushrooms, and above all, one has never stopped growing, that is the "decentralized" marketplace of OpenSea operating on the blockchain of Ethereum and of Polygon recently.

Today, we will more technically analyze this famous platform to understand some anomalies that the NFT sector carries with it and the OpenSea platform, which has never communicated even one episode of problem relating to the site, as one user pointed out on Twitter.

The first problem that concerns OpenSea but all marketplace platforms is the retrieval of the information contained within the Ethereum addresses, as, due to the way the Ethereum blockchain is structured and designed, smart contracts are assigned to addresses and not vice versa; this means that the NFT belongs to the smart contract and not to our only address.

The problem that is reflected on how to retrieve information about NFTs on our addresses, which is not easy as it is necessary to start from block 0 on the Ethereum blockchain and check every single block to find the ERC-721 and ERC-1155 tokens, and once the search is completed, we take the information of the related NFT such as the tokenURI, tokenID, current owner and previous owners, just to mention some information.

It is no coincidence that wallets are unable to show the NFTs we possess, only with some versions is it possible to do this as the system is not scalable and therefore requires extra work, and to do so once the information is retrieved in the method described above, the same are placed inside a centralized database for easy access such as MySQL.

The problem that we do not find on the EOS blockchain as it works as a system with alphanumeric accounts of up to 12 characters, not only can we know how many NFTs we have, but we can see them directly with a block explorer, in this case, the NFTs of account B1:

To check, just take any NFT, for example, this, we can take the smart contract address from OpenSea, and the ID, which in our case is:

65527720056005055004101960054013571584243562889481162860434194461045118992394

and enter it in the URI field of the smart contract to check the information related to that NFT:

And here we have the output that is the call of a centralized OpenSea API in which the so-called metadata is saved, and this is the result of what we see:

{"success": false}

This means that the APIs that OpenSea is using on Polygon is not ready, and in fac,t if we use a tool to check our NFTs, we see that we will have an error as it cannot retrieve the URI information:

From this, it follows that most of the NFTs that we find on Polygon are centralized and have little decentralization because these NFTs would hardly be able to be seen from other parts as the information and APIs are internal to OpenSea, and as we have seen the only one since it returns us it is {"success": false}, furthermore the only way to view it is only through OpenSea and no other tool or wallet, and if you try to scrape the data to get the information, we will have the famous error 1020.

It also follows that to check the information; we must go through its APIs, which are on its centralized site, where we will discover that the images are saved on centralized storage such as Google "https://lh3.googleusercontent.com" and its servers "https: //storage.opensea.io/files/ ":

api.opensea.io/v1/metadata/smart contract address / ID number

If we consider that that information is on centralized structures, it is easy to understand that if those servers go off, we lose the content of the NFT itself; in the following example, this problem is better understood.

By checking another NFT that we find on OpenSea, this one for example, and always using the NFT check platform, we discover that the NFT is saved on a centralized server:

An interesting curiosity is that, due to the limitations of these platforms and how they manage data, we also have different outputs even though we start from the same NFT and address and smart contract, in this case, I leave you the comparison between the same NFT, the first as it is shown on OpenSea and the second as it is shown on Rarible, remember that it is the same NFT:

https://opensea.io/assets/0x5c61afa47570ab2b562606fa578221305b12c307/1

https://rarible.com/token/0x5c61afa47570ab2b562606fa578221305b12c307:1

Impressive right?

But we can go further and check thousands of NFTs to find that most are leveraging centralized databases rather than the blockchain, and this suggests that not all that is gold glitters, as is the case with NFTs.

Even if most of them have that centralized system, some NFTsexploitt a better system than centralized databases, which is that of the IPFS (InterPlanetary File System), certainly they are not a miracle, but they offer at least some more guarantees than a server centralized that can go off overnight it would be advisable for OpenSea to use the IPFS protocol by default to load everything instead of exploiting its centralized database, but as history has taught us, OpenSea is a private company that has been valued over 13 billion dollars by choosing the path from the IPO (Initial Public Offering) rather than choosing a more decentralized path such as a token of your own with the creation of a DAO.

Instead, the AtomicHub marketplace, located on the EOS blockchain, automatically saves any data of our NFT on the relative IPFS protocol, or we can enter the IPFS address ourselves where we will have uploaded our file.

Just to have an example, here is what a good NFT should look like, with no connection to any centralized platform, where I can know all the metadata of the same:

{"image":"ipfs://QmWA4NVxvNCMqp452tLgCyK3DsCrGSu6uecQzVJbD2N8FA","attributes":[{"trait_type":"Mouth","value":"Bored Unshaven Cigarette"},{"trait_type":"Hat","value":"Horns"},{"trait_type":"Fur","value":"Blue"},{"trait_type":"Background","value":"New Punk Blue"},{"trait_type":"Earring","value":"Silver Hoop"},{"trait_type":"Eyes","value":"Closed"}]}

The OpenSea paradox

If, as we have seen, OpenSea, but also other platforms (see Sorare), saves data on centralized databases, what sense does it make to enter the same in web 3.0 or with our wallet? We might as well use web 2.0, using a Google account or from another platform, given that however important data remain centralized and there is little data in the blockchain, yet badly arranged.

Access to a decentralized system and by its nature that uses web 3.0 to a platform that then uses centralized and traditional web 2.0 systems, in my opinion, is a real paradox, a paradox that unfortunately, those who are not in the sector, such as municipalities actors who have approached this sector, are completely ignorant.

The next time you want to create an NFT on Polygon with OpenSea or use its platform, it will be better to investigate this aspect and check if our NFT is on advanced and decentralized systems rather than on the server of some centralized company.

I don’t believe in the centralization on OpenSea, fine, just read this tweet from OpenSea support where they say, from now on, everyone can mint only 50 NFT and create max 5 collections:

https://twitter.com/opensea_support/status/1486651385793769477

Finally, for Italian readers, I made a video explaining all the processes in this article: