Recently, I decided that I needed to better understand what goes on in the backend of cryptocurrency. I've slowly been trying to teach myself to comprehend the various backend protocols.
However, I'm a little confused about
this. From my understanding, the "base point" G should be a point, with both an x and a y value. However, it's given there as a single value, with a compressed and uncompressed form. The linked pdf doesn't seem to elaborate on this. What does this number mean, and how do you derive the x and y of the base point from it?
Thanks in advance.
An EC curve point is compressed by abbreviating the way the Y coordinate is expressed. There are really only two possible values of Y for any X, thus we only need to indicate if it is either positive or negative(1 bit).
while this isn't exactly a standard, more of a convention, typically you take the first byte off(the 0x04 in the uncompressed point) and then the remaining data is two 32 byte integers. As you can see from the example there in your link, in the compressed format, only the X coordinate of G is fully expressed.