Yea, but somehow the PRAM would need to be loaded with some values before the mac would know what image to fetch, Where its at, and possible/if any credentials to get to it.
Maybe default values in ROM, or a special control panel that takes place of "startup disk" and sets that.
Either that, or make a image server that the mac listens to a broadcast message from. Once found, it locks onto the IP from the broadcast originator, fetches a default boot image and off it goes. But this would only work on a local network, or a VPN network.
But all this requires a ROM level network driver. With many many different network card configurations, the network boot code would almost need to be on the network card ROM like in the PC world. So once the DeclRom gets called and loaded, it adds code into RAM to be able to boot from the network with that particular card. Same way SCSI cards do it that allow you to be able to boot from that particular card, as it patches in overtop of the current SCSImanager inside ROM.
You could patch over the .Sony driver in ROM from the DeclRom if it works that way, I dunno. But one would have to look in a book and find out how SCSI cards did it. And then use that code/method to make it work for NICs.
Macs with on board NICs, just find the DeclRom info on that nic and modify it, or just stick it in main ROM and handle it there. But before boot can even happen, you would have to load the NIC DeclRom, then some sort of low-level ROM based network driver/TCP/IP stack.
Maybe default values in ROM, or a special control panel that takes place of "startup disk" and sets that.
Either that, or make a image server that the mac listens to a broadcast message from. Once found, it locks onto the IP from the broadcast originator, fetches a default boot image and off it goes. But this would only work on a local network, or a VPN network.
But all this requires a ROM level network driver. With many many different network card configurations, the network boot code would almost need to be on the network card ROM like in the PC world. So once the DeclRom gets called and loaded, it adds code into RAM to be able to boot from the network with that particular card. Same way SCSI cards do it that allow you to be able to boot from that particular card, as it patches in overtop of the current SCSImanager inside ROM.
You could patch over the .Sony driver in ROM from the DeclRom if it works that way, I dunno. But one would have to look in a book and find out how SCSI cards did it. And then use that code/method to make it work for NICs.
Macs with on board NICs, just find the DeclRom info on that nic and modify it, or just stick it in main ROM and handle it there. But before boot can even happen, you would have to load the NIC DeclRom, then some sort of low-level ROM based network driver/TCP/IP stack.