Public Switched Telephone Network (PSTN) and cellular networks are two distinct communication systems that serve different purposes and utilize different technologies. Let’s explore the key differences between PSTN and cellular networks:
PSTN (Public Switched Telephone Network):
1. Infrastructure:
- Wired Infrastructure: PSTN relies on a wired infrastructure, using copper or fiber-optic cables to connect telephone lines and switching centers.
- Centralized Switching: Calls in the PSTN are typically routed through centralized switching offices.
2. Connection Type:
- Circuit-Switched: PSTN primarily uses circuit-switching technology, establishing a dedicated circuit for the duration of a call.
3. Mobility:
- Limited Mobility: PSTN is designed for stationary landline telephony, lacking the mobility features associated with cellular networks.
4. Coverage:
- Geographic Coverage: PSTN coverage is typically limited to specific geographic regions, and expansion may involve extensive infrastructure development.
5. Technology:
- Analog and Digital Technology: PSTN historically used analog technology, but modern implementations often involve digital technologies such as ISDN (Integrated Services Digital Network).
Cellular Networks:
1. Infrastructure:
- Wireless Infrastructure: Cellular networks are wireless, with cell towers and base stations providing coverage over specific geographic areas.
- Decentralized Switching: Calls in cellular networks can be routed through multiple base stations and switching centers, allowing for decentralized call management.
2. Connection Type:
- Circuit-Switched and Packet-Switched: Cellular networks support both circuit-switched (for voice calls) and packet-switched (for data services) technologies.
3. Mobility:
- High Mobility: Cellular networks are designed for high mobility, allowing users to make calls and access data services while on the move.
4. Coverage:
- Wide Geographic Coverage: Cellular networks provide widespread coverage, including urban, suburban, and rural areas. Coverage expansion is more flexible due to the wireless nature of the infrastructure.
5. Technology:
- Digital Technology: Cellular networks predominantly use digital technologies, with generations like 2G, 3G, 4G, and 5G representing advancements in mobile communication standards.
Common Aspects:
1. Voice and Data:
- Both PSTN and cellular networks support voice communication, but cellular networks also provide data services, allowing for internet access, messaging, and other digital applications.
2. Interconnection:
- There are points of interconnection between PSTN and cellular networks, enabling calls between fixed-line phones and mobile phones.
3. Evolution:
- Both technologies have evolved over time, with PSTN transitioning from analog to digital, and cellular networks progressing through generations of technology (2G, 3G, 4G, 5G).
Summary:
In summary, PSTN is a wired network primarily designed for stationary landline telephony, whereas cellular networks are wireless, mobile communication systems that support voice and data services over a wide geographic area. The key distinctions lie in their infrastructure, mobility features, and technology implementations.