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2

Don't overthink, it's fairly simple. When a frame arrives at an L3 switch, it is forwarded according to its destination MAC address. With normal L2 switching, the destination is a node off one of the switch ports. If that destination MAC is the L3 switch itself (more precisely, one of its L3/routing/SVI interfaces), the encapsulated IP packet is passed to ...


0

The easiest way to understand what's happening is to look at each layer one at a time. IP When Host1 sends a packet to Host2 it consults its local routing table. The possible outcomes are: Host2 is located within Host1's local subnet = the gateway to Host2 is a local interface: the packet is sent directly to Host2 using the interface indicated by the ...


2

It may help to distinguish what is happening at the IP level (and would behave differently if you were using a different protocol at the routed layer), what is happening at the Ethernet level (and would behave differently if you were using a different protocol at the link layer), and what is happening in the middle (the packet encapsulation, as well as the ...


8

To complement the other answers: The first thing a host (or router, which is just a host with multiple interfaces and packet forwarding between interfaces enabled) does is check its routing table. The most basic routing table will usually have: one entry for the local network, pointing to the relevant interface one default route, pointing to the default ...


3

There are 3 pieces of information that your computer needs in order to do this. In a typical setup, they're all provided by DHCP. If you assign a static IP address, you have to provide them all to make this work. We're going to start off providing the both pieces of data that are missing. We'll set the subnet mask of both networks to 255.255.0.0. We'll set ...


17

The sending device uses the subnet mask to determine if the remote host is in it's local network or not. If the IP is within the subnet of the local machine, it uses ARP to determine the MAC address of the remote host. If it's outside, it queries it's local routing table to find the next hop of that IP, and sends out an ARP query to find the MAC address ...


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