Peer-to-Peer vs. Client-Server Networks

Peer-to-Peer (P2P) Networks

• Definition: Every device acts as both a server and a client.
• Advantages:
  • Easy deployment (just install on all devices).
  • No need for a dedicated server.
  • Cost-effective since it uses existing devices.
• Disadvantages:
  • Difficult to administer and ensure security.
  • Distributed authentication process.

Client-Server Networks

• Definition: Responsibilities are split between clients and centralized servers.
• Advantages:
  • Good performance due to direct server connection.
  • Easier administration and centralized configuration.
• Disadvantages:
  • Requires extra hardware and software (servers).
  • Increased complexity and costs.

Types of Networks

Local Area Network (LAN)

• Definition: Network within a single building or close proximity.
• Characteristics:
  • High-speed connections (802.11 wireless, ethernet).
  • Limited to local areas.

Metropolitan Area Network (MAN)

• Definition: Network that spans a city-sized area.
• Characteristics:
  • Often provided by third-party city providers, sometimes called metro ethernet.
  • Used by governments and organizations with spread-out locations.

Wide Area Network (WAN)

• Definition: Network that covers a large geographical area.
• Characteristics:
  • Slower throughput compared to LAN.
  • Uses technologies like MPLS, satellite communication, and point-to-point connections.

Wireless Local Area Network (WLAN)

• Definition: LAN using wireless technology (typically 802.11).
• Characteristics:
  • Limited geographic area.
  • Can be extended using multiple access points.

Personal Area Network (PAN)

• Definition: Small network for personal devices (e.g., Bluetooth).
• Characteristics:
  • Connects personal devices like headsets, keyboards, and car audio systems.

Campus Area Network (CAN)

• Definition: Network that connects multiple buildings within a local area (e.g., school campuses).
• Characteristics:
  • High-speed ethernet connections.
  • Privately run without third-party involvement.

Storage Networks

Network Attached Storage (NAS)

• Definition: Centralized storage accessible over a network at the file level.
• Characteristics:
  • File-level access (changes to entire files).
  • Suitable for large storage needs.

Storage Area Network (SAN)

• Definition: Centralized storage with block-level access.
• Characteristics:
  • Appears like a local drive to computers.
  • Allows block-level data changes, more efficient than NAS.

Wide Area Network Technologies

MPLS (Multiprotocol Label Switching)

• Definition: WAN tech using labels for routing data.
• Characteristics:
  • Supports various connection types and data forms.
  • Centralized initial configuration for site locations.

DMVPN (Dynamic Multipoint VPN)

• Definition: Creates dynamic network connections as needed.
• Characteristics:
  • Uses MGRE (Multipoint Generic Router Encapsulation).
  • Creates and tears down connections based on need.

SD-WAN (Software-Defined WAN)

• Definition: Flexible WAN guided by software to optimize routing.
• Characteristics:
  • Ideal for cloud-based applications.
  • Routes data based on type, directly to cloud services if needed.
• Before SD-WAN:
  • Remote sites had to connect through central data centers.
• After SD-WAN:
  • Data can route directly to cloud-based services, improving efficiency.