Tag: ccie-rs

NAT and Route-Map

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Scenario: Your network has two connections to the outside world. One is used for the Internet and the other one connects to a partner. You are using NAT to translate the IP addresses of your LAN but you…

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ICMP Router Discovery Protocol (IRDP)

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Scenario: As the senior network engineer for “Groceries ‘r’ Us” you are responsible for all routing within the company. The network you are running is fairly old and doesn’t support any fancy routing protocols. Your routers seem to…

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IP Service Level Agreement (SLA)

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Scenario: As the senior network engineer for “Groceries ‘r’ Us” you are responsible for all routing within the company. Every now and then you have links that are still in the up/up state but you are unable to…

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DHCP Authorized ARP

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Scenario: You work as a network engineer for a Hotel offering Internet access for a hourly rate. Recently you notice that some customers have been spoofing MAC and IP addresses to get free access by pretending they are…

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DHCP Proxy

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Scenario: You used to have a DHCP server for each VLAN but this wasn’t much of a scalable solution. You decide to get rid of all the DHCP servers and install a single DHCP server in the datacenter….

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DHCP Server On-Demand Addres Pool

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Scenario: Your network has many serial links running PPP. You heard some good things about DHCP and how you can create on-demand pools using IPCP. Let’s see if it works the way you expect… Goal: Configure both routers…

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Proxy ARP

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Scenario: One of the trainees has configured your network and has assigned static IP addresses to all computer in the network. Unfortunately he made some errors and the computers are not able to reach each other. Think you…

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Transparent IOS Firewall

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Scenario: You are part of the security team for the Rotterdam Harbor located in The Netherlands. One of your firewalls has crashed and due to decreased IT budgets you don’t have any spare firewalls around. You do have…

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ACL Selective IP Options Drop

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Scenario: You are the security office for the national security team in the Netherlands. One of your routers has a very high CPU load and after looking closely you can see it’s spending a lot of cycles processing…

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Control Plane Policing

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Scenario: You are the security office for the national security team in the Netherlands. Recently you did everything in order to protect the data plane of your routers. The only you haven’t done yet is securing the control…

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