title: How many Ip addresses does a router need in the following scenario
body: <pre><code>                 eth0      eth0                  eth1       eth1
                  n1============n2----------------n3=============n4
                       LAN1                             LAN2
  </code></pre>
  
  <p>Let <em>n1</em> and <em>n4</em> are nodes or computers.
  Let n2 and n3 are routers, n2 and n3 are connected directly.</p>
  
  <p>IPAddresses <em>n1</em> &amp; <em>n2</em> are <em>172.16.1.1</em> &amp; <em>172.16.1.2</em></p>
  
  <p>IPAddresses <em>n3</em> &amp; <em>n4</em> are <em>172.16.2.2</em> &amp; <em>172.16.2.1</em></p>
  
  <p>Suppose <em>n1</em> wants to send a packet to <em>n4</em>, so in routing table of <em>n2</em> it has entry</p>
  
  <pre><code>    subnet       port
   172.16.2.0/8     2
  </code></pre>
  
  <p>Now, for forwarding the packet via port 2 does the router <em>n2</em> need another ip address?</p>
  
  <p>What is type of link between <em>n2</em> and <em>n3</em>? if it is P2P, for the link to be up do we need another ip address assigned to it? </p>