The Modular QoS CLI (MQC)
This lesson demonstrates how we configure Quality of Service (QoS) on Cisco devices using the modular QoS CLI (MQC) framework.
Classification and Marking
The purpose of the classification and marking process is to reduce the need to repeat complex classification steps at every device along the network path.
Why do we need QoS?
In a typical IP network, the LAN operates at higher speeds (in the Gigabits range), while WAN interfaces run at slower speeds (in the Megabits range).
Lab #2.2 - Overlapping IP ranges
It is common to deal with overlapping IP ranges in mergers, acquisitions, and multi-tenant environments. Connecting two networks with overlapping IPs typically requires NAT techniques to avoid IP conflicts. The scenario shows two companies merging and needing to interconnect their networks.
Lab #2.1 - Internet access
This lesson demonstrates how to configure NAT in real-world scenarios from scratch, walking through the most important parts of the configuration process.
NAT Overload (PAT)
Port Address Translation (PAT), also known as NAT overload, is a type of Network Address Translation (NAT) that allows multiple devices on a local network (with private IP addresses) to share a single public IP address to access external networks, such as the Internet.
Dynamic NAT
Dynamic NAT (Network Address Translation) is a method of dynamically mapping private IP addresses to public IP addresses from a predefined pool of public IPs.
Static NAT
A device, such as a router or firewall, can change the IP address information in the packets' headers while packets pass through. This network function is called Network Address Translation (NAT) and is shown in the diagram below.
Why do we need NAT?
Network Address Translation (NAT) is a network capability that allows a device (typically a router or a firewall) to modify the IP address information in the IP packet headers while in transit. NAT is most commonly used to enable multiple devices on a private network to access the internet using a single public IP address, which helps conserve the limited number of IPv4 addresses available.
Cisco Discovery Protocol (CDP)
Cisco Discovery Protocol (CDP) is a Layer 2 network protocol used by Cisco devices to discover and share information about directly connected devices in the same network. CDP operates on Cisco routers, switches, IP phones, and other devices, allowing them to discover each other. The protocol simplifies gathering information about network devices and helps administrators better understand the network topology.