Is the internet like a phone call or like sending WhatsApp messages? Most people think it’s the same. It’s not

Transport Networks
,
1

Every time you make a call or send data, the network has to decide:
Do I reserve a full path for you or share it with others?
This single decision defines how communication systems work.

EXPLANATION

  1. Dedicated Path (Circuit Switching)
    • A fixed path is established between sender and receiver
    • Resources (bandwidth, links) are reserved for one user
    • Path stays active for the entire session
    Example: Traditional phone calls
    Even if you’re silent, resources are still occupied

  2. Shared Path (Packet Switching)
    • No fixed path
    • Data is broken into small packets
    • Each packet can take different routes to reach destination
    • Network resources are shared among multiple users
    Example: Internet, WhatsApp, video streaming
    Resources are used only when data is actually sent

  3. Resource Usage Difference
    • Circuit Switching:
    ○ Predictable performance
    ○ But wastes resources when idle
    • Packet Switching:
    ○ Highly efficient
    ○ But can have delay, congestion, packet loss
    Trade-off = Efficiency vs Predictability

  4. Setup vs On-Demand Transmission
    • Circuit Switching:
    ○ Requires setup phase before communication starts
    ○ Once set → smooth, continuous flow
    • Packet Switching:
    ○ No setup required
    Data is sent instantly, packet by packet

ANALOGY

Think of it like transportation:
Circuit Switching = Reserved Train Compartment
• You book the entire compartment
• It’s yours for the journey
• Even if seats are empty → no one else can use them
Packet Switching = Public Road Traffic
• No reservation
• Cars (packets) take different routes
• Roads are shared with others
• Faster utilization, but possible traffic (delay)

TAKEAWAY

• Circuit Switching = Dedicated, predictable, but inefficient
• Packet Switching = Flexible, efficient, but variable performance
Modern networks chose efficiency → that’s why the internet runs on packet switching.

Stage 1: Why Networks Exist → “Birth of Communication Networks”
Track: Foundations
Part 2

2

The internet is more like sending WhatsApp messages, not a phone call. A phone call is a continuous real time connection, while internet data is broken into small packets and sent separately, then reassembled. So it’s not one constant stream, but many tiny messages moving across networks.

3

There is Zero to very little Circuit Switching in Modern telecommunication networks.The term is still used only to differentiate Voice Core and Packet Core.Everything travel as data now no more circuits.

4

A good point to add is that while LTE and 5G are fully packet-switched networks, not all packets are treated equally. Services like VoLTE use dedicated QoS bearers with strict latency and packet loss requirements, whereas regular web browsing or file downloads typically use best-effort traffic. So, even though everything is transmitted as IP packets, the network prioritizes different services differently to ensure a good user experience.