CCNA Cram Sheet - Networking Fundamentals - CCNA Exam Cram

Sep 30, 2026

Uploaded by asba

CCNA Cram Sheet for exam review focusing on core networking fundamentals and study recall. Summarizes OSI and TCP/IP model layer functions, the PDUs for lower layers, and key UDP versus TCP behavioral differences including overhead, connection orientation, ordering, reliability, and multiplexing via port numbers. Includes common protocols mapped to OSI layers, a well-known port numbers reference table, and a detailed exam-oriented table of contents covering network components, topology, cabling, IPv4/IPv6, wireless, virtualization, switching, VLANs, discovery protocols, and spanning tree concepts.

LanguageEnglish

CategoryExam

FormatPDF

Pages13

Reading Time33 min

AccessFree to download

Networking Fundamentals

The OSI and TCP/IP Models

The PDUs of the Bottom Four Layers

UDP vs TCP

Protocols at Various Layers of the OSI Model

Well-Known Port Numbers

CCNA 200-301 Exam Cram

Part I: Network Fundamentals

Chapter 1: The Role and Function of Network Components

Chapter 2: The Characteristics of Network Topology Architectures

Chapter 3: Physical Interfaces and Cabling Types

Chapter 4: Describe TCP and UDP

Chapter 5: Configure and Verify IPv4 Addressing and Subnetting

Chapter 6: Configure IPv6

Chapter 7: Describe Wireless Principles

Chapter 8: Explain Virtualization Fundamentals

Chapter 9: Describe Switching Concepts

Part II: Network Access

Chapter 10: Configure and Verify VLANs and Interswitch Connectivity

Chapter 11: Configure and Verify Layer 2 Discovery

Chapter 12: Describe Rapid PVST+ Spanning Tree Protocol

Chapter 13: Compare Cisco Wireless Architectures and AP Modes

The CCNA Cram Sheet This Cram Sheet contains key information as a final preparation tool for the CCNA exam. Review this information as the last thing you do before you enter the testing center, paying special attention to those areas in which you think that you need the most review. Enjoy this additional study aid! Networking Fundamentals The OSI and TCP/IP Models OSI—the layers are Application, Presentation, Session, Transport, Network, Data Link, Physical; TCP/IP—the layers are Application, Transport, Internet, Network Interface. The PDUs of the Bottom Four Layers Segments, Packets, Frames, Bits |
Protocols at Various Layers of the OSI Model
Layer Examples | | | --- | --- | | Application | FTP, [HTTP](HTTP), SMTP | | Presentation | JPEG, MPEG | | Session | NetBIOS, PPTP | | Transport | TCP, UDP | | Network | IP, ICMP | | Data link | PPP, ATM | | Physical | Ethernet, USB | UDP is connectionless; UDP has very little overhead; UDP is often used for voice and video traffic forms; UDP can multiplex using port numbers to work with multiple applications. TCP is connection-oriented; TCP has more overhead than UDP; TCP uses features like flow control, sequencing and acknowledgements to ensure reliable and ordered delivery of segments; TCP can multiplex using port numbers to work with multiple applications. | APPLICATIONS | THAT | USE | TC | P/UDP | | | --- | --- | --- | --- | --- | --- | | TCP | | | | UDP | | | [HTTP](HTTP) | | | | DHCP | | | FTP | | | | RIP | | | Telnet | | | | SNMP | | | SSH | | | | TFTP | | | SMTP | | | | *DNS | | |
Well-Known Port Numbers
Port Number (s) TCP or UDP? Protocol | | | | --- | --- | --- | | 20 | TCP | FTP data | | 21 | TCP | FTP control | | 22 | TCP | SSH | | 23 | TCP | Telnet | | 25 | TCP | SMTP | | 53 | UDP | DNS | | 67, 68 | UDP | DHCP | | 69 | UDP | TFTP | | 80 | TCP | [HTTP](HTTP) | | 110 | TCP | POP3 | | 161 | UDP | SNMP | | 443 | TCP | SSL/TLS | | 514 | UDP | Syslog | | 520 | UDP | RIP | CCNA 200-301 Exam Cram Table of Contents Cover Title Page Copyright Page Credits Contents at a Glance Table of Contents Preface About the Author Dedication Acknowledgments About the Technical Reviewer Introduction Part I: Network Fundamentals CHAPTER 1: The Role and Function of Network Components Topic: Explain the role and function of network components Topic: Next-generation firewalls and IPS Topic: Controllers (Cisco DNA Center and WLC) Cisco DNA Center Wireless LAN Controllers (WLCs) Review Questions Table of Contents Answers to Review Questions Additional Resources CHAPTER 2: The Characteristics of Network Topology Architectures Topic: 2-tier architectures and 2-tier spine-leaf The 2-Tier Spine-Leaf Topic: WANs and SOHOs WANs SOHOs Topic: On-premises and cloud On-Premises Cloud Review Questions Answers to Review Questions Additional Resources CHAPTER 3: Physical Interfaces and Cabling Types Topic: Single-mode fiber, multimode fiber, copper Multimode Versus Single-Mode Fiber Ethernet Shared Media Versus Point-to-Point Power over Ethernet (PoE) Serial Connections Topic: Troubleshoot interface and cable issues (collisions, errors, duplex, speed) Review Questions Answers to Review Questions Additional Resources CHAPTER 4: Describe TCP and UDP Topic: Compare and contrast the OSI and TCP/IP models Topic: Compare and contrast TCP and UDP Table of Contents Review Questions Answers to Review Questions Additional Resources CHAPTER 5: Configure and Verify IPv4 Addressing and Subnetting Topic: Configure, verify, and troubleshoot IPv4 addressing and subnetting Topic: Compare and contrast IPv4 address types Topic: Describe the need for private IPv4 addressing Topic: Verify IP parameters for client OS (Windows, Mac OS, Linux) Review Questions Answers to Review Questions Hands-On Lab Practice Assignment Configure and Verify IPv4 Addressing Additional R

FAQs

What are the OSI and TCP/IP model layers covered in the cram sheet?

The document lists OSI layers as Application, Presentation, Session, Transport, Network, Data Link, and Physical, and TCP/IP layers as Application, Transport, Internet, and Network Interface.

How does UDP differ from TCP according to this reference?

UDP is connectionless with very little overhead and is often used for voice and video traffic; it can multiplex with port numbers. TCP is connection-oriented, has more overhead, and uses flow control, sequencing, and acknowledgements to ensure reliable, ordered delivery while also multiplexing with port numbers.

Which protocol-to-layer and port number references are included for quick study?

The cram sheet provides a mapping of common protocols to OSI layers (e.g., FTP, HTTP, SMTP, TCP/UDP-based examples) and a table of well-known port numbers showing which transport (TCP or UDP) and protocol use each port.

Sep 30, 2026

Uploaded by asba