Tag:   NAT

This post represents the solution and explanation for quiz-22. It presents how fragmented traffic is handled differently by a simple access list. It is a long read about fragmentation, Path MTU Discovery, MSS and other stuff...

Your company has 3 sites, each with a dedicated border router, R1, R2 and R3.
Site-1 (R1) and Site-2 (R2) have their own internet uplinks, but Site-3 (R3) connects to internet via R2. A GRE tunnel is built between R2 and R3 and applied an MTU of 1440, due to some constraints in the transit network between them. You notice that traffic between same pair of devices works for TCP 1001 but fails for TCP 1002. What's wrong ?

Your company has a border router (R2) that is connected to two partner companies: Partner-DB (R1) providing database services and Partner-APP (R3) that provides different application services to your web servers in DMZ (200.200.200.0/24). You are requested to configure NAT according to some requirements.

This post represents the solution and explanation for quiz-11. A very important topic when configuring Network Address Translation (NAT) is the order of operation. Who is performed first: NAT or Routing ?

This post represents the solution and explanation for quiz-9. There are some challenges to allow an authenticated MD5 BGP session via a firewall, involving TCP Options. Let's see what happens!

Your company makes a new contract with a Partner Company for a new research project. To provide network connectivity, NAT is being configured on your side but something does not work as desired. What is it?

This post represents the solution and explanation for quiz-3.
NAT on Cisco IOS can be pretty frustrating sometimes and it may take time and practice to master it.

As a network administrator, you've been requested to allow the internal clients to connect to a partner server 3.3.3.3 on port 12345. Unfortunately, you discover that your ISP blocks traffic on that TCP port 12345 and allows only some well-known ports, including 8080. How do you implement this ?