Si kusok mimo.
Bolo by fajn si najprv nastudovat co to modem je a naco sluzi. Modem nemoze mat nat, fw a pod, pretoze je to modem a prevadza signal z ethernet rozhrania na coaxial.
Niektore modemy mozu mat v sebe jednoduche routre, ale v tom pripade ma modem vlastnu ip a mac adresu a vacsinou obsahuju aj dhcp server.
Toto je to podstatne na com by si mohol pochopit ako modem funguje:
Layer 1 is implemented in the Ethernet PHY on its LAN interface, and a DOCSIS defined cable-specific PHY on its HFC cable interface. The term cable modem refers to this cable-specific PHY. The Network Layer (Layer 3) is implemented as a IP host in that it has its own IP address used by the network operator to maintain the device. In the Transport Layer (Layer 4) the cable modem supports UDP in association with its own IP address, and it supports filtering based on TCP and UDP port numbers to, for example, block forwarding of NetBIOS traffic out of the customer's LAN. In the Application Layer (Layer 7), the cable modem supports certain protocols that are used for management and maintenance, notably DHCP, SNMP, and TFTP.
ISO-OSI model predpoklam poznas ked sa tu tak fundovane vyjadrujes;o).