Abcon-Tech

27/09/2026

COMMON NETWORKING ABBREVIATIONS - Lecture Note

Prepared by: Abass Conteh - IT Officer & Lecturer

1. BASIC ADDRESSING & NETWORK TYPES
- IP - Internet Protocol: Unique address for every device on a network. Like a house address. e.g `192.168.1.10`
- MAC - Media Access Control: Permanent hardware address of a network card. e.g `00:1A:2B:3C:4D:5F`
- LAN - Local Area Network: Network limited to small areas like office, lab, home.
- WAN - Wide Area Network: Network that spans large areas, e.g. internet.
- SSID - Service Set Identifier: The name of a Wi-Fi network you see on your phone.

2. CORE SERVICES THAT MAKE INTERNET WORK
- DNS - Domain Name System: Translates human names to IP. `google.com` -> `142.250.x.x`
- DHCP - Dynamic Host Configuration Protocol: Automatically gives IP addresses to devices. Without it you have to type IP manually.
- NAT - Network Address Translation: Allows many devices to share one public IP. Done by your router.
- ARP - Address Resolution Protocol: Finds MAC address from IP address.

3. DATA TRANSPORT PROTOCOLS
- TCP - Transmission Control Protocol: Reliable, ordered delivery. For browsing, email. Like registered mail.
- lUDP - User Datagram Protocol: Fast, no guarantee. For video calls, gaming, streaming.
- QoS - Quality of Service: Prioritizes important traffic (e.g. Zoom over downloads).

4. WEB & FILE TRANSFER
- HTTP - HyperText Transfer Protocol: Protocol for web communication.
- HTTPS - Secure version: HTTP + Encryption (SSL). Has a padlock icon.
- FTP - File Transfer Protocol:Transfers files over a network.

5. EMAIL PROTOCOLS
- SMTP - Simple Mail Transfer Protocol: SENDS email.
- POP3 - Post Office Protocol 3: DOWNLOADS email and deletes from server.
- IMAP - Internet Message Access Protocol:ACCESSES email while keeping it on server. Best for phone + PC.
Private Network: Secure encrypted tunnel over internet.
- ICMP - Internet Control Message P

06/09/2026

Phone showing Storage full but you didn't download anything. The process of how to clear memory.

06/09/2026

Let's learn how the network later operates

The 7 Layers of the OSI Model Explained 🌐

Ever wondered how your message gets from your phone to a server on the other side of the world?

The OSI Model breaks it down into 7 layers. Each layer has one job:

Application- `HTTP, FTP, SMTP` - What you use
Presentation- `Encryption, Compression` - How data looks
Session - Manages connections
Transport- `TCP, UDP` - Reliable delivery
Network - `IP` - Finds the route
Data Link - `Ethernet, WiFi` - Local delivery Physical- Cables, fiber, signals

From request to response, every click goes through all 7.

Which layer do you work with the most? 👇

06/09/2026

🔆 POWER YOUR HOME & BUSINESS WITH SOLAR 🔆
From Abcon-Tech - Freetown

Tired of blackouts and fuel costs? We’ve got the solution ☀️

IN STOCK NOW AT ABCON-TECH:
- Solar Panels: All sizes available - small, medium & large for homes, shops, and farms
- Solar Home Generators: Plug-and-play green units. Run lights, TV, fans, fridge
- Inverters, Controllers & PV Combiner Boxes: Safe, complete systems
- Solar Street Lights: Light up your compound, street, and community

Clean energy. Lower bills. 24/7 power.

📍 Visit Us: Freetown
📲 Call/WhatsApp: 078247330
📩 DM us for prices, free consultation & installation

Let the sun pay your bills. Switch to solar with Abcon-Tech today!

29/08/2026

The 7 Layers of the OSI Model Explained 🌐

Ever wondered how your message gets from your phone to a server on the other side of the world?

The OSI Model breaks it down into 7 layers. Each layer has one job:

Application- `HTTP, FTP, SMTP` - What you use
Presentation- `Encryption, Compression` - How data looks
Session - Manages connections
Transport- `TCP, UDP` - Reliable delivery
Network - `IP` - Finds the route
Data Link - `Ethernet, WiFi` - Local delivery Physical- Cables, fiber, signals

From request to response, every click goes through all 7.

Which layer do you work with the most? 👇

18/08/2026

📱 Phone saying “Storage Full” but you didn’t download anything? 😩

Here are 3 hidden space-eaters you should check on your phone in Freetown 👇🏾

1️⃣ WhatsApp “Sent” videos 🎥
2️⃣ Telegram cache 📂
3️⃣ Old APK files 📦

🧹 Quick fix:
Go to Settings → Storage and check what’s taking up the most space. Then clear unnecessary files and cache.

⚠️ Tip: Don’t delete important photos, videos, or documents without checking them first!

💾 Save this post so you don’t forget!

Which app is taking most of YOUR storage? 👇🏾
Drop the app name in the comments!

14/08/2026

Running a shop? I highly recommend the Eastpoint Retail Manager App — it makes sales, stock, and reporting super easy. 100% safe and secure. Download now: https://eastpointepb.com/

14/08/2026

How to Connect Hotspot on an Android phone
Part 1: Turn ON Hotspot on Your Phone

For Android
1. Open Settings
2. Tap Network & Internet> Hotspot & Tethering
3. Tap Wi-Fi Hotspot
4. Toggle ON
5. Tap the hotspot name to see the SSID and Password. You can also tap Edit to change them.
Abass Potho Conteh

10/08/2026

TYPES OF ETHERNET CABLE

1. CAT5e CABLE
- Speed: Up to 1 Gbps
- Frequency: Up to 100 MHz
- *Notes*: Most common for basic home and small office networks. Affordable, handles internet, streaming, and light gaming fine.
- *Best for*: Everyday use where gigabit is enough

2. CAT6 CABLE
- Speed: Up to 10 Gbps
- Distance: 10 Gbps up to 55 meters
- Frequency: Up to 250 MHz
- Notes: Thicker wires + better twisting than CAT5e. Less crosstalk and interference.
- Best for: Homes/offices that want faster speeds without going overboard

3. CAT6a CABLE
- Speed: Up to 10 Gbps
- Distance: 10 Gbps up to 100 meters
- Frequency: Up to 500 MHz
- Notes: "a" = augmented. Better shielding than CAT6, so it maintains 10Gbps over full 100m runs.
- Best for: Businesses, larger buildings, future-proofing

4. CAT7 CABLE
- Speed: Up to 10 Gbps
- Distance: Up to 100 meters
- Frequency: Up to 600 MHz
- Notes: Each pair + overall cable is shielded. Great noise reduction. Uses GG45 or TERA connectors sometimes, but RJ45 works too.
- Best for: Environments with lots of electrical interference

5. CAT8 CABLE
- Speed: Up to 25/40 Gbps
- Distance: Up to 30 meters
- Frequency: Up to 2000 MHz
- Notes: Heavily shielded. Designed for data centers and server rooms. Not ideal for long home runs due to distance limit.
- Best for: Highest speed, shortest distance, pro equipment

6. OUTDOOR ETHERNET CABLE
- Speed: Depends on CAT rating inside - usually CAT5e/6/6a
- Notes: Weather-resistant, UV-protected jacket. Can be direct burial rated. Protects from rain, sun, and temperature swings.
- *Best for*: Connecting buildings, cameras, access points outside

7. FLAT ETHERNET CABLE
- Speed: Depends on CAT rating inside - usually CAT5e/6/6a
- Notes: Flat ribbon design. Easy to tuck under carpets, along baseboards, or through tight spaces. More flexible but slightly more prone to interference.
- Best for: Clean home/office installs where cable needs to be hidden

Key

06/08/2026

The Big Picture: How the Internet Gets Into the Office
Think of it like water flowing through pipes, but instead it's data.

1. Internet from ISP → Comes in through the ISP Router. This gives the office a Public IP address so it can connect to the internet.
2. Firewall (Fortinet) → Acts like a security guard. It blocks hackers, handles VPN if people work from home, and separates different parts of the network using VLANs.
3. Manageable Switch → This is the "traffic controller" in the middle. Every wired device plugs into it. It decides where data should go inside the office.

What’s Connected in the Office

1. Internet & Wi-Fi Devices
- WiFi Access Point: Gives wireless internet to Laptops and Mobiles
- Wired Devices: 10 Desktops, more Laptops, Common Printer, Time Attendance System for clocking in/out, and CCTV Cameras for security. All of these connect through cables to the Switch.

2. Office Systems
- Yeastar IP PABX This is the office phone system. The IP Phones connect to it, and it connects to the switch so you can make calls over the internet.
- Proxmox Server: This is the "office brain". It runs virtual computers for things like:
- File Server: storing shared files
- AD/DNS/DHCP: logging in users and giving IP addresses
- Applications and Backups
- NAS Storage: Like a big shared hard drive for the whole office. Used for file storage, shared folders, and backups.

Extra Smart Stuff

Network Summary:
Internet → Router → Firewall → Switch → Everything else
Plus: Office phones, server, storage, Wi-Fi, CCTV, attendance system, and printer.

VLAN Suggestion:
This is just a way to keep things organized and secure. Imagine different "lanes" on the same road:
- VLAN 10: DATA - for regular computers
- VLAN 20: VOICE - for office phones
- VLAN 30: SERVER - for Proxmox and NAS
- VLAN 40: CCTV - for cameras
- VLAN 50: GUEST WIFI - so visitors don't access office files
- VLAN 99: MANAGEMENT - for IT to manage everything