Netgear Switch Discovery Protocol Explained

NTDS (Netgear Switch Discovery Protocol)
Level:Прикладной
Family:TCP/IP
Ports:63321, 63322, 63323, 63324
Purpose:Netgear level 2 switch management

Netgear Switch Discovery Protocol (NSDP) is a management protocol for several network device families, designed by Netgear.

Message structure

Common message header

OffsetLengthMeaning
0x00001Proto version – always 0x01
0x00011Operation code: may be 0x01 – read request, 0x02 – read response, 0x03 – write request, 0x04 – write response
0x00022Operation result
0x00044Unknown
0x00086host MAC-address
0x000e6network device MAC-address (value 00:00:00:00:00:00 is used as multicast address, request will be proceeded by all devices, which would receive it)
0x00142Unknown
0x00162Sequence number (value increments with every next request)
0x00184Protocol signature NSDP
0x001С4Unknown
0x0020NMessage body – the sequence of TLV records
0x0020 + N4End of message marker 0xFFFF0000

Message body record structure

Message body records are type–length–value (TLV) structures. Type field may be one of following values in the table(list in incomplete):

TypeMeaning
0x0001Device model
0x0003Device given name
0x0004Device MAC-address
0x0005Device system location
0x0006Device current IP-address (may be unsupported by certain devices)
0x0007Device IP-network mask (may be unsupported by certain devices)
0x0008Router IP-address (may be unsupported by certain devices)
0x000aadministration password
0x000bDHCP Mode (Refresh DHCP = 2, DHCP = 1, Static = 0)
0x000dDevice Firmware version slot 1 (may be unsupported by certain devices)
0x000eDevice Firmware version slot 2 (may be unsupported by certain devices)
0x000fNext active firmware slot after reboot (01 = 1, 02 = 2, may be unsupported by certain devices)
0x0c00Speed/link status of ports
0x1000Port Traffic Statistic
0x2800Get VLAN info
0x2c00Delete VLAN (write only)

Protocol flow examples

Network devices discovery (MAC-address an device model discovery): Host with MAC=XX:XX:XX:XX:XX:XX from UDP-port 63321 or 63323 sending packet to broadcast IP-address 255.255.255.255 and UDP-port 63322 or 63324 Header @0x00000000 0x01 0x01 0x000000000000 0xXXXXXXXXXXXX 0x000000000000 0x0000 0x0001 0x4E534450 0x00000000 Body @0x00000020 0x0001 0x0000 0x0004 0x0000 Marker @0x00000028 0xFFFF0000

EACH Device responds with message like Header @0x00000000 0x01 0x02 0x000000000000 0xXXXXXXXXXXXX 0xYYYYYYYYYYYY 0x0000 0x0001 0x4E534450 0x00000000 Body @0x00000020 0x0001 0x0028 0x47 0x53 0x31 0x30 0x35 0x45 0x20*0x22 0x0004 0x0006 0xYYYYYYYYYYYY Marker @0x00000058 0xFFFF0000

Device support for protocol

Devices firmware update

Device firmware update is made with TFTP protocol, but you need to send NSDP request to turn on TFTP-server first.

See also

External links