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Hardware Deep Dive: Cisco SFP-10G-SR-S

Topic: Networking Hardware | Author: 0x5ha157 | Status: Analysis

In the world of homelabs and enterprise networking, 10 Gigabit Ethernet (10GbE) is the standard for backbone connectivity. I recently acquired a set of Cisco transceivers for my switch uplinks. Below is a technical breakdown of the hardware.

1. Visual Identification

Based on the physical inspection of the module, we can decode exactly what hardware we are dealing with.

Cisco SFP Top View Label
Fig 1. Top label view identifying the model number and specifications.

The label provides the critical data:

2. Technical Specifications

The SFP-10G-SR-S is part of Cisco's "S-Class" optics. It is designed for multimode fiber (MMF) applications.

Feature Specification
Form Factor SFP+ (Enhanced Small Form-factor Pluggable)
Data Rate 10 Gbps (10 Gigabit Ethernet)
Wavelength 850 nm (Nanometers)
Connector Duplex LC
Max Distance 300m (OM3 Fiber) / 400m (OM4 Fiber)

3. The "S-Class" Distinction

You might notice the -S at the end of the model number. This distinguishes it from the standard SFP-10G-SR.

4. Physical Architecture

SFP LC Connector View
Fig 2. The Optical Interface (Duplex LC).

The Optical Interface: Figure 2 shows the optical bore. The SFP+ uses a Vertical-Cavity Surface-Emitting Laser (VCSEL) to transmit light at 850nm.

SFP Side View CLEI Code
Fig 3. Side view showing the CLEI code (CMUIAK6CAA).

CLEI Code: The sticker reading CMUIAK6CAA is the Common Language Equipment Identifier. This 10-character alphanumeric code is used by the telecommunications industry to identify equipment types and features uniformly.

5. Installation & Commands

When inserting this into a Cisco switch (like a Catalyst or Nexus), the golden fingers on the bottom mate with the switch port contacts.

SFP Bottom Contacts
Fig 4. The electrical interface (20-pin edge connector).

To verify the module status in the CLI, use the following commands:

# Check transceiver details
Switch# show interface transceiver details

# Verify inventory and serial numbers
Switch# show inventory

# If using non-Cisco hardware (generic unlock)
Switch(config)# service unsupported-transceiver
SFP Modules Stacked
Fig 5. The SFP+ metal housing acts as a heat sink and EMI shield.