🔌

Transceivers Overview and Types

Sep 2, 2025

Overview

This lecture discusses transceivers, focusing on their modularity, types, and form factors used in networking equipment to support different media and network speeds.

Transceiver Basics

  • A transceiver combines a transmitter and receiver in a single device.
  • Transceivers are modular, allowing different media types on each switch interface.
  • Swapping transceivers enables switching between copper and fiber connections as needed.
  • Transceivers add cost but offer flexibility for diverse network requirements.

Types and Compatibility

  • Different transceivers exist for different network types (e.g., Ethernet, Fiber Channel).
  • Ethernet transceivers cannot be used in Fiber Channel switches and vice versa.
  • Users can change connection types by swapping appropriate transceivers.

SFP and SFP+ Transceivers

  • SFP (Small Form-factor Pluggable) transceivers support 1 Gbps connections, typically used for Gigabit Ethernet.
  • SFP+ (Enhanced SFP) transceivers look identical in size but support higher speeds up to 16 Gbps, commonly used for 10 Gbps links.

Quad SFP and SFP+ (QSFP/QSFP+)

  • QSFP (Quad SFP) allows four channels of SFP in a single, slightly larger form factor.
  • QSFP achieves up to 4 Gbps with standard SFP channels and 40 Gbps with SFP+ channels.
  • QSFP provides greater throughput in the same or less space compared to multiple SFPs, improving rack efficiency.
  • Quad SFPs are not four times the size of a standard SFP, delivering space efficiency gains.

Key Terms & Definitions

  • Transceiver — A device that transmits and receives signals, supporting communication between network devices.
  • SFP (Small Form-factor Pluggable) — A compact, hot-swappable transceiver for 1 Gbps connections.
  • SFP+ — An enhanced version of SFP that supports speeds up to 16 Gbps.
  • QSFP (Quad Small Form-factor Pluggable) — A transceiver supporting four channels, increasing total throughput up to 40 Gbps.

Action Items / Next Steps

  • Review the types of transceivers available for your network equipment.
  • Identify which transceiver form factors are compatible with your hardware.
  • Prepare to distinguish between SFP, SFP+, and QSFP transceivers in practical scenarios.