Had fun with this lesson… especially the “Packets Unplugged” router activity that suggests you re-config the desks in your classroom in the form of the capital letter ‘H’.
I have desktop boxes on each of my desks in 4 rows of eight. Rearranging the desks into an ‘H’ is not feasible because of the wiring, etc. It turns out that you don’t need to rearrange your desks… if you add a couple of little tweaks.
The preparation for the activity is the same. Each student prepares a message consisting of four parts, or packets. In my room, I number the students with an IP address according to the row and the desk in the row that they sit in. When the students are doing their prep, I walk around and assign each student a destination (another student) by random selection (in my case, a desk of cards). The students then label the packets with the destination address in the upper right corner. I instruct the students to hold the “packets” in their hand like they would hold cards in a card game. In this way, all of the destination addresses are easily visible at a glance.
The next phase is the packet “routing”. In my variation, I include a timer and tell each student they have a “router table” that can only hold 4 entries. The timer I selected was 15 seconds. I only allow the students to pass one packet once every 15 seconds. I silently count and then yell out “Pass!”. The student then looks at the packet(s) received and determines if the packet(s) should be delivered (e.g. removed from their hand and placed on their desk) or remain in play to be passed along to the next “router”. After that, the students must then count the packets in their hand and discard packets until they only have four remaining. These packets are crumpled up and are effectively “dropped” from the simulation.
The same lesson objectives are achieved. The routers on the edges of the network - especially those in the four corners - do not see as much traffic as those in the center of room. I teach four sessions of this class and in each one when I asked “Raise your hand if you had to drop packets during the simulation.”, almost all of the raised hands were in the center of the seating arrangement.