Where to start developing a router?

Question

Do it yourself

Good afternoon.
Where to start developing a router?
I work in telecom. Mikrotik, DLINK, Alcoma, ITellite, these and other manufacturers are constantly on the table in the form of ready-made devices. RouterOS, OpenWRT and other operating systems are familiar and studied inside and out. Network planning, equipment configuration and other joys of a network engineer.
I'm interested in how this whole thing works at a low level and I want to develop my own, simple router. To begin with, I want to try to create a simple L2 switch with two ports and a simple firewall.
Please send me a sample study plan.
I ask you not to advise to disassemble the Chinese piece of iron and copy it, I am interested in a full study of the process.
Ready to share news if anyone is interested.

Answer 1

To get started, buy river sand.

Answer 2

Do you want to create your own hardware? I don't want to sound impolite, but this is extremely expensive and difficult for a single person (although theoretically possible). Buy a board with an FPGA + ARM type SoC (for example, Zynq 7000 or Zynq UltraScale), and with the right number of ports, and smoke Verilog, SystemVerilog, network protocols, verification techniques (UVM). Enough for a few years.
Then it will be possible to make your own version of the board, here you will need to smoke CAD, signal integrity, high-speed wiring (all sorts of DDR3 and DDR4), installation methods and technologies, buy a good oscillator and a log. analyzer (not with Ali), and other junk for several tens of thousands of dollars. In general, this is possible.

Answer 3

look at datasheets for atheros broadcom mediatek chips they have English documentation and a wiring diagram in the same way choose memory order printed circuit boards assemble test and forward firmware it is better to use open source code for example OpenWRT