copy of Computer Networking and DDI.pptx

Computer Networking and DDI;Network Topology

1. Computer Networking and DDI

2. Computer Network A system of interconnected devices (such as computers, servers, routers, and switches) that communicate and share resources using communication protocols over wired or wireless connections

3. Key Components Computer Network

4. Network Types LAN – Local Area Network (e.g., office) WAN – Wide Area Network (e.g., Internet) PAN – Personal Area Network (e.g., Bluetooth) MAN – Metropolitan Area Network WLAN - Wireless Local Area Network (e.g., Wifi) Computer Network

5. Network Topology Computer Network Point to point Bus Star Ring Mesh Hybrid Tree

6. Protocol Layers OSI & TCP/IP Model

7. Common Services DNS – Resolves domain names DHCP – Assigns IP addresses dynamically IPAM (e.g., QIP) – Manages IP allocation DDI

8. IP Address (Internet Protocol)

9. Definition A unique numerical identifier assigned to each device connected to a network Allows devices to locate and communicate with each other across networks IP Address

10. Types Public IP : Used to identify a network on the internet Private IP : Used within a local network (LAN). Static IP : A fixed IP address that does not change Dynamic IP : be provided by the DHCP server, which can change IP address

11. Versions IP address IPv4 IPv6 Older and more widely used version The newer version, designed to replace IPv4 Length 32-bit Length 128-bit Format : xxx.xxx.xxx.xxx ( Each group represents a number between 0 and 255 ) Format : xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx ( Each section consists of a hexadecimal value ) ~4.3 billion (2³²) addresses ~340 undecillion (2¹²⁸) addresses

12. Subnet Subnetwork

13. Definition Subnet: A smaller network that is split from a larger parent network. Subnet Mask: Separates the IP address into network and host portions.(Decimal & CIDR formats) IP Address: [Network] + [Host] IP address

14. Benefits of Subnetting: Helps divide a large network into smaller —> more manageable segments Enhances security and optimizes performance Saves IP address space Separates networks for users, servers, departments, etc. IP address

15. How to Subnet

16. Problem Given the 192.168.1.0 /24 network, you want to create subnets that can support 50 hosts each Subnetting

17. Preparation Ask yourself one of these questions: How many subnets do I need? How many hosts do I need per subnet? -> 50 hosts → This determines your subnet mask and subnet size. Subnetting

18. Step 1 – Identify Base IP and Subnet Mask IP: 192.168.1.0 Subnet mask: /24 → 255.255.255.0 Subnetting

19. Quick Reference Table for Subnetting Subnetting CIDR (Classless Inter-Domain Routing) Subnet Mask Number of subnets (from /24) Host/Subnet (Available) /25 255.255.255.128 2 126 /26 255.255.255.192 4 62 /27 255.255.255.224 8 30 /28 255.255.255.240 16 14 /29 255.255.255.248 32 6 /30 255.255.255.252 64 2

20. Step 2 – Calculate the number of required hosts Each subnet need to have at least 50 usable hosts. Choose a subnet with at least 52 addresses (since 2 addresses are reserved). /26 subnet (62 usable hosts) is suitable. 4 subnet (from reference table) Subnetting

21. Step 3 – Calculate the block size (subnet increment) /26 → Subnet mask: 255.255.255.192 The last octet is 192 , so: → Block size = 256 – 192 = 64 This means each subnet will increase by 64 addresses in the last octet (e.g., 0, 64, 128, 192, 255). Subnetting

22. Step 4: List the Subnets Subnetting Subnet Network Address Usable IP Broadcast 1 192.168.1.0 192.168.1.1 - 192.168.1.62 192.168.1.63 2 192.168.1.64 192.168.1.65 - 192.168.1.126 192.168.1.127 3 192.168.1.128 192.168.1.129 - 192.168.1.190 192.168.1.191 4 192.168.1.192 192.168.1.193 - 192.168.1.254 192.168.1.255

23. Tools Subnetting Online : SubnetOnline.com , IPCalc.org , DNSstuff Subnet Calculator App : IP Calculator, Subnet Calculator Linux: ipcalc, sipcalc

24. DNS (Domain name service)

25. DNS (Domain name service) A system resolves human-readable domain names into IP addresses DDI

26. How DNS works DNS

27. DNS Records DNS Type Full Name A Address AAAA IPv6 Address CNAME Canonical Name NS Name Server TXT Text SOA Start of Authority

28. DNS Hierarchical DNS

29. Step 1: Register and Own a Domain Name Step 2: Set Up a DNS Server Step 3: Create a DNS Zone for the Domain Step 4: Add DNS Records Step 5: Save and v erify DNS Configuration DNS Configuration steps DNS

30. DNS checker tools Window: nslookup example.com Linux/ macOS : dig exmaple.com Online: DNS Checker DNS

31. DHCP (Dynamic Host Configuration Protocol)

32. Definition DHCP A protocol used to automatically assign IP addresses to devices (clients) on a network.

33. How DHCP works DHCP works through a 4 main steps (DORA) DHCP

34. How to use DHCP Step 1: Install/Enable DHCP Server Step 2: Define DHCP Scope/Pool (IP range) IP address pool Subnet mask Default gateway DNS servers Lease duration Step 4: Save config and start the DHCP service Step 5: Verify DHCP

35. IPAM (IP Address Management)

36. Definition A system used to plan, track, and manage IP addresses and related network information. Tools support: Microsoft IPAM SolarWinds Infoblox phpIPAM IPAM

37. Key Functions of IPAM Track IP usage across subnets Manage static and dynamic IP assignments Integrate with DHCP and DNS servers Detect IP conflicts and duplicate IPs Automate IP address discovery and updates IPAM

38. Benefits Prevents IP duplication and conflicts Improves visibility and control of IP space Enables easier network scaling and planning Automates manual IP tracking (e.g., no more Excel sheets) IPAM

39. Defects

40. Definition Defects are technical errors that occur during the design, configuration, deployment, or operation of a network. They can cause: Loss of connectivity Reduced speed Service interruptions (downtime) Security vulnerabilities Negative impact on user experience Defects

41. Types of Network Defects Hardware defects Configuration defects Connectivity defects Wireless defects Security defects Software or Protocol Defects Defects

42. Causes of Network Defects Faulty hardware devices (routers, switches, cables) Misconfigurations (DHCP, routing, VLANs) System overload (limited bandwidth, too many devices) Software bugs or outdated firmware External factors (cyberattacks, electromagnetic interference) Defects

43. Troubleshooting and Prevention: Monitor (Wireshark, PRTG, SolarWinds) Real-time notifications (Setup SNMP alerts) Update firmware regularly Implement network segmentation (VLANs/subnets) Strengthen security controls (firewalls, IDS/IPS) Defects

44. Q & A

45. THANKS