Advanced Networking Reviewer

For Final Exam

Networking Fundamentals

• A network is a collection of devices connected together to share data and resources. The main purpose is to provide access to information and communication services.

• LAN

• WAN

LAN

Connects devices in a small area such as an office or school.

WAN

• Covers a large geographic area such as the internet.

• The Internet is the largest ___ in existence.

TCP/IP Model

• Application Layer

• Transport Layer

• Internet Layer

• Link Layer

• The ___ inspired the OSI model but uses only 4 layers instead of 7.

Application Layer

Handles user interaction (HTTP, FTP, SMTP).

Transport Layer

Ensures end-to-end delivery (TCP, UDP).

Internet Layer

Logical addressing and routing (IP, ICMP).

Link Layer

Deals with physical connections (Ethernet, MAC).

Switches and MAC Addresses

• ___ operate at Layer 2 (Data Link) and forward frames based on ___ stored in their ___ table.

• A ___ is a 48-bit unique identifier burned into the network interface card.

Cisco CLI and Configuration Modes

• ___ devices use Command Line Interface (CLI) modes for configuration and troubleshooting.

• User EXEC mode

• Privileged EXEC mode

• Global Configuration mode

• Interface Configuration mode

• Using '?' in CLI lists available commands starting with a specific letter.

User EXEC mode

Basic monitoring (Switch>)

Privileged EXEC mode

Advanced monitoring/config (Switch#)

Global Configuration mode

System-wide settings (Switch(config)#)

Interface Configuration mode

Port-specific settings (Switch(config-if)#)

VLANs and Trunking

• VLAN (Virtual Local Area Network) divides a switch into smaller broadcast domains. 802.1Q ___ allows ___ to span multiple switches.

• VLAN 1 is the default VLAN in Cisco switches.

Spanning Tree Protocol (STP)

• ___ prevents Layer 2 loops in switched networks by organizing ports into states: Blocking, Listening, Learning, Forwarding.

• Root Bridge

• Root Port

• Designated Port

• Without ___, a simple loop can cause a broadcast storm that crashes the network.

Root Bridge

The central reference point in STP.

Root Port

Lowest cost path to the root bridge.

Designated Port

Best path for a given segment.

IP Addressing and Subnetting

• IPv4 uses 32 bits, IPv6 uses 128 bits. IPv6 solves the problem of IPv4 address exhaustion.

• IPv4 has about 4.3 billion addresses, while IPv6 supports 340 undecillion addresses.

Routing Concepts

• Directly Connected

• Static Route

• Dynamic Route

• Default Route

• OSPF uses a link-state algorithm, while EIGRP uses a hybrid approach.

Directly Connected

Automatically added when interfaces are up.

Static Route

Manually configured by an administrator.

Dynamic Route

Learned through protocols like RIP, OSPF, or EIGRP.

Default Route

Used when no specific route exists (0.0.0.0/0).

WAN Concepts

• WANs connect devices across long distances using service providers. Examples include MPLS, VPNs, and leased lines.

• WANs are slower and more expensive than LANs due to distance and infrastructure.

Network Security

• Network devices can be secured through passwords, banners, and disabling unused ports.

• Console and VTY password protection.

• Message of the Day (MOTD) banners for login warnings.

• Disable unused ports using 'shutdown' or 'port-security'.

• A well-configured switch can prevent unauthorized devices from joining the network.