Routing and Switching

Routes

Routes are the backbone for most of the internet. It is a system of costs that help manage where traffic is supposed to go. Even for many in computers, the whole internet itself seems like a hard target. This is an illusion.

All it takes is for one computer to have a bad route or not be on the same page to mess up things. As one of my teachers put it, Pakistan made the mistake of blacklisting Youtube by black holing the domain. This works, but if you set the "cost" too low and your computers share that route with the whole world, suddenly the whole world tries to go through Pakistan to get to Youtube because the cost is low. Youtube is of course blacklisted in Pakistan.

• ip route [Incoming IP] [Incoming Subnet] [Outgoing Interface] [Next Hop Address] [Distance/Cost]

         0.0.0.0          0.0.0.0      10.19.114.1     10.19.114.81     35
     10.19.114.0    255.255.255.0         On-link      10.19.114.81    291
    10.19.114.81  255.255.255.255         On-link      10.19.114.81    291
   10.19.114.255  255.255.255.255         On-link      10.19.114.81    291
       127.0.0.0        255.0.0.0         On-link         127.0.0.1    331
       127.0.0.1  255.255.255.255         On-link         127.0.0.1    331
 127.255.255.255  255.255.255.255         On-link         127.0.0.1    331
    192.168.56.0    255.255.255.0         On-link      192.168.56.1    281
    192.168.56.1  255.255.255.255         On-link      192.168.56.1    281
  192.168.56.255  255.255.255.255         On-link      192.168.56.1    281
   192.168.126.0    255.255.255.0         On-link     192.168.126.1    291
   192.168.126.1  255.255.255.255         On-link     192.168.126.1    291
 192.168.126.255  255.255.255.255         On-link     192.168.126.1    291
   192.168.154.0    255.255.255.0         On-link     192.168.154.1    291
   192.168.154.1  255.255.255.255         On-link     192.168.154.1    291
 192.168.154.255  255.255.255.255         On-link     192.168.154.1    291
       224.0.0.0        240.0.0.0         On-link         127.0.0.1    331
       224.0.0.0        240.0.0.0         On-link      192.168.56.1    281
       224.0.0.0        240.0.0.0         On-link     192.168.126.1    291
       224.0.0.0        240.0.0.0         On-link     192.168.154.1    291
       224.0.0.0        240.0.0.0         On-link      10.19.114.81    291
 255.255.255.255  255.255.255.255         On-link         127.0.0.1    331
 255.255.255.255  255.255.255.255         On-link      192.168.56.1    281
 255.255.255.255  255.255.255.255         On-link     192.168.126.1    291
 255.255.255.255  255.255.255.255         On-link     192.168.154.1    291
 255.255.255.255  255.255.255.255         On-link      10.19.114.81    291