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def handle_dhcp_message(self, data, client_addr): # Parse DHCP Header (simplified) # Message Type (1 byte), Hardware Type (1), Hw Addr Len (1), Hops (1) # Transaction ID (4), Seconds (2), Flags (2), Client IP (4), Your IP (4) # Server IP (4), Gateway IP (4), Client MAC (16)...
# Send and wait for ACK while True: try: transfer_socket.sendto(packet, client_addr) ack_data, _ = transfer_socket.recvfrom(1024)
dhcp_thread.start() tftp_thread.start()
The client broadcasts a DHCP Discover message. dhcp tftp
In the world of network administration, certain protocols are so intertwined that they are often discussed as a single unit. and TFTP (Trivial File Transfer Protocol) form one such partnership. Together, they serve as the backbone for PXE booting, VoIP phone provisioning, and diskless workstation operations.
TFTP simply waits for a request and sends the file. It is the "delivery truck" of the pre-boot environment. 3. The Handshake: How They Work Together
packet += socket.inet_aton("0.0.0.0") # Client IP packet += socket.inet_aton(client_ip) # Your IP (Assigned IP) packet += socket.inet_aton("0.0.0.0") # Server IP packet += socket.inet_aton("0.0.0.0") # Gateway IP and TFTP (Trivial File Transfer Protocol) form one
TFTP uses port 69 only for the initial request.
class TFTPServer: def __init__(self): self.socket = socket.socket(socket.AF_INET, socket.SOCK_DGRAM) self.socket.bind((SERVER_IP, TFTP_PORT)) if not os.path.exists(TFTP_ROOT_DIR): os.makedirs(TFTP_ROOT_DIR)
A completely diskless machine pulls an OS from the network, no USB stick required. It is the "delivery truck" of the pre-boot environment
Brands like Cisco and Polycom use DHCP to find a TFTP server that holds their latest firmware and specific line configurations.
The client acknowledges the IP and notes the TFTP server location.
| Protocol | Use case | Why not here? | |----------|----------|----------------| | | Simple, tiny footprint | No authentication, UDP-based. Fits in BIOS/UEFI firmware easily. | | FTP | File transfer with auth | Too heavy for pre-boot environment. | | HTTP | Web transfers | Many modern UEFI implementations support HTTP boot now, but TFTP is still the legacy standard. |