1.What is ERC-3525

FT token (Token) or NFT (Non-fungible token), which everyone must be well acquainted with, are homogeneous tokens and non-homogeneous tokens, respectively, the former is each the same, the latter is each different. Both of which have described the physical world in as much detail as possible, in reality there are some assets that are mostly the same, but there are some odd cases, which seems a bit out of place to be described by FT or NFT. This is drove the development of ERC-3525, which defines a new asset class, Semi-Fungible Token (SFT). As the name implies, ERC-3525 sits somewhere between FT and NFT.

Compared with the conventional ERC-20/ERC-721 and its value to value/ID to ID, the ownership and asset transfer relationship does not depict the tokenized digital asset with a structure, and neither meets the needs of the application layer at this stage, such as the asset redemption rules are more complex, and a wide range of asset attributes can not be displayed with a single value and ID. ERC-3525 protocol redefines the assets, which further allows the expansion and compatibility of assets to be vastly enhanced.

Although the previous section briefly defined what ERC-3525 is, here is a detailed example that can help you to gain a better grasp on what it truly is. Let’s take a land in this case, first thing first, a piece of land certainly cannot be FT, because each land is different, but each land is mostly the same, there may be a little nuance that is different, i.e. the location, the infrastructure, and etc. But mark it with NFT, the land that is not widely different is as unique as a work of art, and it would be very troublesome and unnecessary to revalue each one of them when they are circulated on the market. By now using ERC-3525 to define the land, it is not only possible to let people know that each land is different, but also to let them know which parts are slightly different. 

2. What is SFT?

The SFT under the ERC-3525 standard solves this problem perfectly.

An SFT token is depicted by 3 aspects ID, SLOT and VALUE.

The ID attribute is equivalent to the ID of the NFT and is used to identify its own distinctive nature.

SLOT is the property that describes the asset, such as the size of the land, accessibility, age, and other properties. If two SFTs have identical properties, they are substitutable like FTs. Value is used to represent quantity just like FT.

SFT tokens can be completely transferred from one wallet address to another just like NFT, and only a portion of the slot value can be transferred between SFT tokens through slots like FT, such as transferring only “zoning” of the land to another piece of land.

There is no doubt that SFT is more customizable than FT and more efficient than NFT. Here we look at ERC-3525 through three more perspectives.

3. SFT structures

ERC-3525 from Owner’s perspective

ERC-3525 from Transfer’s perspective

ERC-3525 from Structure’s perspective

Slot contains various IDs, which are assigned with different values. In a smart contract, 3525 tokens of the same slot can be transferred to each other, while different slots cannot be transferred. Compared with the traditional ERC-20 and ERC-721, ERC-3525 protocol has higher scalability and compatibility than the other two, and a vast number of conventional businesses can be applied to the chain through ERC-3525 protocol.