Network+ (N10-009) Objective 2.0: Network Implementations

Network Devices Overview
Common hardware devices used in network implementations

Network Connectivity Devices

Devices that establish connectivity and forward traffic between network segments

Router

A network device that forwards data packets between computer networks, directing traffic to their intended IP networks.

Key Characteristics:

  • Operates at Layer 3 (Network Layer) of the OSI model
  • Uses IP addresses to make forwarding decisions
  • Creates boundaries between networks
  • Connects different network types (e.g., LAN to WAN)

Functions:

  • Determining the best path for data using routing protocols
  • Connecting multiple networks and subnets
  • Filtering traffic based on IP addresses via ACLs
  • NAT (Network Address Translation) for converting private IPs to public IPs
  • Traffic filtering and basic security features
Exam Note: Know the difference between routers and Layer 3 switches. Understand common routing protocols (OSPF, EIGRP, BGP) and their use cases.
Layer 2 Switch

A network device that connects devices within the same network (LAN) and uses MAC addresses to direct traffic at the data link layer.

Key Characteristics:

  • Operates at Layer 2 (Data Link Layer) of the OSI model
  • Uses MAC addresses to make forwarding decisions
  • Maintains a MAC address table (CAM table)
  • Creates separate collision domains for each port

Functions:

  • Connecting end devices within the same LAN
  • Filtering and forwarding frames based on MAC addresses
  • VLAN segmentation to break up broadcast domains
  • Loop prevention through Spanning Tree Protocol (STP)
  • Link aggregation for increased bandwidth and redundancy
Exam Note: Understand switch operation including MAC address learning, forwarding, flooding, and filtering. Know the purpose of STP and how VLANs work on switches.
Layer 3 Switch

A hybrid network device that combines the functionality of a Layer 2 switch with basic routing capabilities.

Key Characteristics:

  • Operates at both Layer 2 and Layer 3 of the OSI model
  • Uses hardware-based routing for better performance
  • Maintains both MAC address and routing tables
  • Typically used in LAN environments for inter-VLAN routing

Functions:

  • High-speed LAN switching
  • Inter-VLAN routing without external router
  • Access control through ACLs
  • Quality of Service (QoS) implementation
  • Support for routing protocols like OSPF and EIGRP
Exam Note: Compare Layer 3 switches with traditional routers. Know that Layer 3 switches typically offer better performance for inter-VLAN routing but may have limited WAN protocol support.
Wireless Access Point (WAP)

A networking device that allows wireless-capable devices to connect to a wired network using Wi-Fi.

Key Characteristics:

  • Operates at Layers 1 and 2 of the OSI model
  • Converts frames between 802.3 (Ethernet) and 802.11 (WiFi) formats
  • Can be standalone or controller-based
  • Supports various authentication and encryption methods

Functions:

  • Providing wireless connectivity to wired networks
  • Broadcasting SSIDs for network identification
  • Authenticating wireless clients
  • Encrypting wireless traffic
  • Handling roaming between access points in larger deployments
Exam Note: Know the differences between autonomous, controller-based, and cloud-managed APs. Understand basic wireless security protocols (WPA2/WPA3) and authentication methods.
Media Converter

A device that converts one type of media transmission to another, typically between copper and fiber optic cabling.

Key Characteristics:

  • Operates at Layer 1 (Physical Layer) of the OSI model
  • Typically transparent to the network
  • Available in various form factors (standalone, rack-mount, SFP)
  • Supports different speeds and duplex modes

Functions:

  • Converting between different media types (e.g., copper to fiber)
  • Extending network distances beyond copper limitations
  • Allowing integration of different media technologies
  • Mode conversion between multimode and single-mode fiber in some cases
Exam Note: Understand when media converters are necessary and their common use cases. Know the distance limitations of different media types that make converters necessary.