Which two OSI model layers have the same functionality as two layers of the TCP/IP model? (Choose two.)

The OSI model's Network and Transport layers match the functionality of the Internet and Transport layers in the TCP/IP model. These layers handle routing, addressing, and reliable data transfer. For more clear explanations and exam prep, visit Study4Pass your trusted source for IT certification success.

Tech Professionals

15 April 2025

Cisco

Which two OSI model layers have the same functionality as two layers of the TCP/IP model? (Choose two.)

Introduction

The Open Systems Interconnection (OSI) model and the TCP/IP model are fundamental frameworks for understanding network communication. While the OSI model consists of seven layers, the TCP/IP model has only four. Despite their structural differences, some layers in both models share similar functionalities.

In this article, we will explore:

The OSI model and its seven layers.
The TCP/IP model and its four layers.
Which two OSI layers correspond to two TCP/IP layers in terms of functionality.
The importance of understanding these models for CCNA, CCDA, CCENT, CCNA Security, and CCNA Wireless exams.
How Study4Pass helps IT professionals master these concepts efficiently.

Overview of the OSI Model

The OSI (Open Systems Interconnection) model was developed by the International Organization for Standardization (ISO) to standardize network communication. It consists of seven layers, each with a specific role:

Layer	Name	Function
7	Application	Provides network services directly to user applications (e.g., HTTP, FTP).
6	Presentation	Translates, encrypts, and compresses data (e.g., SSL, JPEG).
5	Session	Establishes, manages, and terminates connections (e.g., NetBIOS, RPC).
4	Transport	Ensures reliable data transmission (e.g., TCP, UDP).
3	Network	Handles logical addressing and routing (e.g., IP, ICMP).
2	Data Link	Manages physical addressing and error detection (e.g., Ethernet, MAC).
1	Physical	Transmits raw bitstream over physical media (e.g., cables, hubs).

Overview of the TCP/IP Model

The TCP/IP model (also called the Internet Protocol Suite) is a more practical framework used in real-world networking. It has four layers:

Layer	Name	Function	OSI Equivalent
4	Application	Combines OSI's Application, Presentation, and Session layers (e.g., HTTP, SMTP).	Layers 5-7
3	Transport	Ensures end-to-end communication (e.g., TCP, UDP).	Layer 4
2	Internet	Handles logical addressing and routing (e.g., IP, ICMP).	Layer 3
1	Network Access	Combines OSI's Data Link and Physical layers (e.g., Ethernet, Wi-Fi).	Layers 1-2

Which Two OSI Layers Correspond to Two TCP/IP Layers?

When comparing the two models, we find that two OSI layers align directly with two TCP/IP layers in terms of functionality:

A. OSI Transport Layer (Layer 4) = TCP/IP Transport Layer

Both models have a Transport layer that ensures reliable data transmission.
Key protocols: TCP (Transmission Control Protocol) and UDP (User Datagram Protocol).
Functions:

Segmentation (breaking data into smaller units).
Flow control (managing data transmission speed).
Error recovery (retransmitting lost packets).

B. OSI Network Layer (Layer 3) = TCP/IP Internet Layer

Both models handle logical addressing and routing.
Key protocol: IP (Internet Protocol).
Functions:

Logical addressing (IP addresses).
Routing (determining the best path for data).
Packet forwarding (sending data between networks).

These two layers (Transport & Network/Internet) perform nearly identical roles in both models.

Importance for CCNA, CCDA, CCENT, CCNA Security, and CCNA Wireless Exams

Understanding the OSI and TCP/IP models is crucial for networking certifications like:

CCNA (Cisco Certified Network Associate) – Tests foundational networking concepts.
CCDA (Cisco Certified Design Associate) – Focuses on network design principles.
CCENT (Cisco Certified Entry Networking Technician) – Entry-level networking knowledge.
CCNA Security – Requires deep knowledge of network layers for security implementations.
CCNA Wireless – Involves wireless networking protocols across different layers.

Questions like:

"Which two OSI layers match the TCP/IP Transport and Internet layers?"
"What is the function of the OSI Network layer?"

Are common in these exams. Mastering these concepts ensures success in both theoretical and practical networking scenarios.

How Study4Pass Helps You Succeed?

Preparing for Cisco exams can be challenging, but Study4Pass provides the best resources to help you pass with confidence:

Comprehensive Study Guides – Detailed explanations of OSI and TCP/IP models.
Practice Exams – Simulates real Cisco test environments.
Hands-On Labs – Practical exercises to reinforce learning.
Expert Support – Access to networking professionals for doubts.
Updated Material – Aligned with the latest exam objectives.

By choosing Study4Pass, you get a structured learning path that simplifies complex topics, ensuring you’re fully prepared for your certification exams.

Conclusion

The OSI Transport (Layer 4) and Network (Layer 3) layers align with the TCP/IP Transport and Internet layers, respectively. Understanding these models is essential for networking certifications like CCNA, CCDA, CCENT, CCNA Security, and CCNA Wireless.

For the best exam preparation, trust Study4Pass to provide high-quality study materials, practice tests, and expert guidance. Start your journey to becoming a certified networking professional today!

Final Answer:

The OSI Transport layer (Layer 4) and OSI Network layer (Layer 3) have the same functionality as the TCP/IP Transport layer and TCP/IP Internet layer, respectively.

For more in-depth study materials, visit Study4Pass Your ultimate resource for Cisco certification success!