Excuse me, is the subnet mask information stored in each IP datagram first? First seemingly not said mask fields,
Or a subnet mask is stored in the host routing table? But how to confirm the destination host the datagram is which one?

CodePudding user response:

Subnet mask is a PC, layer 3 switches and routers use the matching concept, a packet of byte field has nothing to do,

Often see IP address configuration is that how many IP, mask; Item or routing table XXX,

CodePudding user response:

reference 1st floor yeweimian1 response:

subnet mask is a PC, layer 3 switches and routers use the matching concept, a packet of byte field has nothing to do,

Often see IP address configuration is that how many IP, mask; Or routing table item XXX,

I just ask the subnet mask in where?

CodePudding user response:

IP packet is not including the subnet mask information, for the common single broadcast is 32-bit mask,
IP + mask can identify a child segments, often contain contained in the routing device (such as PC, switches, routers, etc.) in the routing table