Network architecture refers to the design and components of a computer network. It includes end devices, intermediate devices, network media, and protocols that govern communication. There are different network architectures like client-server, peer-to-peer, and cloud-based. The OSI model divides network functionality into seven layers. Key protocols for network communication include TCP/IP, HTTP, FTP, and DNS. Network architecture also involves addressing, routing, switching, firewalls, and wireless networking.

1. Network Architecture and
Protocols
WHTA networks

2. What is network Architecture
Definition: Network architecture refers to the design and layout of a
computer network, including its components and their relationships.

3. Importance of Network
Architecture
● Efficient Communication:
○ Ensures optimal data transfer and communication within the
network.
● Scalability:
○ Allows the network to grow and adapt to changing needs.
● Reliability:
○ Ensures the network's availability and reliability.

4. Components of Network
Architecture
1. End Devices:
○ Computers, servers, smartphones.
2. Intermediate Devices:
○ Routers, switches, firewalls.
3. Network Media:
○ Cables (fiber optic, copper), wireless signals.
4. Protocols:
○ Rules governing communication (TCP/IP, HTTP, etc.).

5. Types of Network Architectures
1. Client-Server Architecture:
○ Clients request services from centralized servers.
2. Peer-to-Peer Architecture:
○ Devices communicate directly with each other without a
centralized server.
3. Cloud-Based Architecture:
○ Services and resources are hosted in the cloud.

6. Layered Network Architecture
● OSI Model (Open Systems Interconnection):
○ Divides network functionality into seven layers.
○ Layers include Physical, Data Link, Network, Transport,
Session, Presentation, and Application.
● Benefits:
○ Simplifies troubleshooting and development.
○ Encourages interoperability among different systems.

7. Key protocols in Network
Communication
1. TCP/IP (Transmission Control Protocol/Internet Protocol):
○ Essential for internet communication.
○ Divided into four layers: Network Interface, Internet, Transport, and
Application.
2. HTTP (Hypertext Transfer Protocol):
○ Used for web communication, defining how messages are formatted
and transmitted.
3. FTP (File Transfer Protocol):
○ Facilitates file transfers between devices.
4. DNS (Domain Name System):
○ Resolves domain names to IP addresses, translating human-readable
names to machine-readable addresses.

8. Addressing in Network
Architecture
● IP Addresses:
○ Unique identifiers for devices on a network.
○ IPv4 with 32 bits and IPv6 with 128 bits.
○ Hierarchical structure for efficient routing.
● MAC Addresses:
○ Physical addresses assigned to network interfaces.
○ Used for local network communication.

9. Routing in Network Arhitecture
● Router Functionality:
○ Directs data packets between different networks.
○ Makes decisions based on routing tables, which contain
information about network paths.
● Routing Protocols:
○ OSPF (Open Shortest Path First), BGP (Border Gateway
Protocol), RIP (Routing Information Protocol).

10. Switching in Network
Architecture
● Switch Functionality:
○ Connects devices within a local network.
○ Uses MAC addresses for forwarding decisions.
○ Improves network efficiency by reducing collision domains.
● Managed Switches:
○ Allow configuration for better control and security.

11. Firewalls in Network
Architecture
● Firewall Definition:
○ Security device that monitors and controls incoming and
outgoing network traffic.
○ Acts as a barrier between internal and external networks.
● Types of Firewalls:
○ Packet Filtering, Stateful Inspection, Proxy Firewalls.
● Unified Threat Management (UTM):
○ Combines multiple security features in one device.

12. VPNS[Virtual Private Network]
● Definition:
○ Securely extends a private network across a public network.
○ Encrypts communication to ensure confidentiality.
● Use Cases:
○ Remote access for employees.
○ Secure communication over the internet.
● Protocols:
○ PPTP, L2TP/IPsec, OpenVPN.

13. Wireless Network Architecture
● Components:
○ Access points, wireless routers, clients.
○ Wi-Fi standards (802.11a/b/g/n/ac/ax).
● Protocols:
○ WPA3, WPA2 for encryption.
○ SSIDs (Service Set Identifiers) for network identification.
● Security Measures:
○ Encryption, strong authentication (WPA3, 802.1X).

14. Network Security Protocols
● Secure Sockets Layer (SSL) and Transport Layer Security
(TLS):
○ Ensure secure communication over a computer network.
○ Used in HTTPS for secure web browsing.
● IPsec (Internet Protocol Security):
○ Provides security at the network layer.
○ Encrypts and authenticates IP packets.

15. Conclusion
● Effective Network Architecture is Crucial:
○ Ensures optimal performance, scalability, and security.
○ Adapts to evolving technological needs.
● Ongoing Evolution:
○ New technologies, such as SDN (Software-Defined
Networking), continue to shape network architecture.