Chapter 3: Common Network Toplogies and Infrastructures¶

Network Topologies¶

Star Topology¶

All devices connect to a central switch or hub
Traffic flows through the central device
Easy to manage and troubleshoot
Vulnerability: failure of the central device affects the entire network

Bus Topology¶

All devices share a single communication line
Simple and low cost
Traffic collisions increase as more devices are added
Vulnerability: break in the main cable disrupts all devices

Mesh Topology¶

Devices connect to multiple or all other devices
High redundancy and fault tolerance
Complex and expensive to implement
Common in mission-critical networks

IP and MAC Addresses¶

IP Address¶

Logical address assigned to a device
Used to identify devices across networks
Commonly viewed using ipconfig and tested with ping

MAC Address¶

Physical hardware address of a network interface
Used for local network communication
Mapped to IP addresses using arp

De-Militarized Zone (DMZ)¶

Network segment exposed to external traffic
Hosts public-facing services such as web or DNS servers
Separated from the internal network by firewalls
Traffic is tightly controlled and monitored
Common focus during firewall and service analysis

Network Devices¶

Switch¶

Connects devices within the same local network
Uses MAC addresses to forward frames

Router¶

Connects multiple networks together
Routes traffic using IP addresses
Often performs NAT and subnetting

Firewall¶

Filters traffic based on security rules
Protects internal networks from unauthorized access
Controls access to the DMZ

Key Concepts¶

Subnetting: dividing networks into smaller logical segments
Logical Topology: how data flows through a network
Client/Server Networks: centralized servers provide services to clients

Purpose of This Chapter¶

This chapter explains why tools like Zenmap and Wireshark are used to analyze network structure, traffic flow, and exposed services in virtual environments.