What are the two general methods for decrypting Zyxel firmware discussed in the article?

The article introduces two methods: first, decrypting ZIP files via a known-plaintext attack using tools like pkcrack; second, obtaining the ZIP encryption password by tracking process parameters with `strace` on a MIPS-emulated environment where `zld_fsextract` runs. Both methods are detailed in the Zyxel Firmware Decryption article.