domain_registry.lua

rednet.open("left")

local name = "domain_name"
local id = os.getComputerID()

local data = {name = name, id = id}
local message = textutils.serialise(data)

rednet.send(126, message, "dns_register")

local senderID, message, protocol = rednet.receive("dns_ack")
print(message)