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Verizon LTE modem + Netgear Router/Switch?
Can a Netgear router or switch (like GS608) be connected to one of the LAN outputs of a Verizon LTE Internet+Phone (aka Broadband+Voice) to successfully expand the number of wired devices? I have 2 P...
jeffs95033 wrote:
even though all devices below the switch appear to the router on only one of its LAN ports, they'll still get assigned unique IP addresses by DHCP and avoid address collisions, right?
Yes, they will get DHCP-assigned IP addresses.
Here's a rough idea of what goes on (likely more than you want to know...).
All ethernet packets also include source/destination mac addresses (in addition to the source/destination IP addresses). These addresses are normally built into the ethernet chips themselves (though routers and some other devices let you set them).
The network stack in your client will learn the destination mac address for every packet it sends, using a protocol called arp. If the destination isn't on the subnet, the destination mac address is the mac address of the router lan port. It remembers this mac address (for every IP address) so it doesn't need to do this for every packet.
Ethernet switches automatically learn what mac addresses are sending traffic through them on every port. If the ethernet switch already recognizes the destination mac address, the packet is automatically sent to the right LAN connection, and the router never sees the packet.
If it doesn't recognize the destination, then it broadcasts the packet (so the whole network, including the router) will receive it. The router doesn't route it, it just ignores it. When a response packet comes back (which it will at some point), the router updates it's mac address tables.
So once the system is up and running, local subnet traffic never touches the router. The LAN ports of the router usually also functions as a hardware ethernet switch, so the processor in the router also shouldn't get engaged with local LAN traffic. Wifi->LAN, WiFi->internet and LAN->internet traffic always do pass the router's processor. The implication here is that the switch might not be necessary to prevent the original concern you posted, but it certainly will ensure that local LAN traffic stays off the router connection. And later on if you deployed a 10gbit lan (upgrading to a 10gib switch), your local traffic could run at much higher speeds than the router can handle.
Thanks much StephenB. So then, even though all devices below the switch appear to the router on only one of its LAN ports, they'll still get assigned unique IP addresses by DHCP and avoid address collisions, right?
jeffs95033 wrote:
even though all devices below the switch appear to the router on only one of its LAN ports, they'll still get assigned unique IP addresses by DHCP and avoid address collisions, right?
Yes, they will get DHCP-assigned IP addresses.
Here's a rough idea of what goes on (likely more than you want to know...).
All ethernet packets also include source/destination mac addresses (in addition to the source/destination IP addresses). These addresses are normally built into the ethernet chips themselves (though routers and some other devices let you set them).
The network stack in your client will learn the destination mac address for every packet it sends, using a protocol called arp. If the destination isn't on the subnet, the destination mac address is the mac address of the router lan port. It remembers this mac address (for every IP address) so it doesn't need to do this for every packet.
Ethernet switches automatically learn what mac addresses are sending traffic through them on every port. If the ethernet switch already recognizes the destination mac address, the packet is automatically sent to the right LAN connection, and the router never sees the packet.
If it doesn't recognize the destination, then it broadcasts the packet (so the whole network, including the router) will receive it. The router doesn't route it, it just ignores it. When a response packet comes back (which it will at some point), the router updates it's mac address tables.
So once the system is up and running, local subnet traffic never touches the router. The LAN ports of the router usually also functions as a hardware ethernet switch, so the processor in the router also shouldn't get engaged with local LAN traffic. Wifi->LAN, WiFi->internet and LAN->internet traffic always do pass the router's processor. The implication here is that the switch might not be necessary to prevent the original concern you posted, but it certainly will ensure that local LAN traffic stays off the router connection. And later on if you deployed a 10gbit lan (upgrading to a 10gib switch), your local traffic could run at much higher speeds than the router can handle.