Physical Interface and Cabling Types refers to the ways in which different devices on the network connect to each other physically, as well as the types of cables used for these connections. This includes the physical ports, connectors, and cables that are used to establish a connection between devices such as computers, routers, and other networking equipment.
Physical Interface and Cabling Types.
i. Cable Types
Copper Cable (Twisted Pair): The most common type, using twisted pairs of insulated wires to transmit data. It comes in categories (Cat) like Cat 5e (1 Gbps) and Cat 6 (10 Gbps), offering different speed capabilities. Copper is cheaper but susceptible to interference and has shorter range.
Single-mode Fiber Optic Cable: Uses thin glass fibers to transmit data as light pulses. Offers high bandwidth, long distances, and immunity to interference but is more expensive and fragile.
Multi-mode Fiber Optic Cable: Similar to single-mode but with a larger core for easier light transmission. Less expensive than single-mode but has lower bandwidth and higher signal dispersion, limiting its reach.
ii. Connections
Ethernet Shared Media (Hub): Connects multiple devices to a central hub. All devices share the same bandwidth, and data transmission can be disrupted by collisions . Hubs are rarely used in modern networks.
Ethernet Point-to-Point (Switch): Connects devices directly, creating dedicated paths. Switches learn device addresses and only send data to the intended recipient, improving efficiency and reducing collisions. Read more on network Switch
iii. Power over Ethernet (PoE)
A technology that allows delivering electrical power along with data over a single Ethernet cable. This eliminates the need for separate power supplies for devices like IP phones or security cameras. PoE devices are designed to be interoperable across various manufacturers, providing a standardized and reliable solution for power and data transmission in networking environments.
iv. Interface and Cable Issues
Collisions: In shared media (hubs), when two devices transmit data simultaneously, the packets collide and need to be resent, causing delays. Switches eliminate this issue.
Errors: Data errors can occur due to noise, signal weakness, or cable damage. Techniques like error correction can help detect and fix these errors.
Duplex Mismatch: Network devices can operate in full-duplex (transmit and receive simultaneously) or half-duplex (take turns transmitting and receiving), e.g switches.
A mismatch can cause data loss. Auto-MDIX (Automatic Medium Dependent Interface Crossover) on some devices can automatically adjust for this.
Speed Mismatch: Devices connected with cables or interfaces that don’t support the same speed will be limited to the lower speed.
v. TCP vs. UDP
These are two main protocols for data transfer over networks:
Transmission Control Protocol (TCP): Offers reliable, connection-oriented communication. TCP establishes a connection, checks for errors during transmission, and re-sends lost data packets. It’s suitable for applications where data integrity is crucial (e.g., file transfers).
User Datagram Protocol (UDP): Provides connectionless, best-effort communication. UDP sends data packets without error checking or guaranteed delivery. It’s faster than TCP but not as reliable. It’s suitable for real-time applications where speed is critical and some data loss is acceptable (e.g., online gaming, streaming).
