CompTIA Network+ Cheat Sheet (Updated for Latest Exam)

You’ve made a brilliant decision aiming for the CompTIA Network+ certification. Given the deluge of information on networking and limited time to prepare for the examination, it can be difficult to decide what aspects of Network+ are high-priority items to review.

Our CompTIA Network+ cheat sheet is handy as an overview or a refresher in such a predicament. It makes an excellent companion to our Security+ cheat sheet, which excludes Network+ material, and it goes deeper into major networking topics than those briefly mentioned in our A+ cheat sheet.

Keep this CompTIA Network+ cheat sheet handy by downloading it here. When you’re ready, let’s dive in.

CompTIA Network+ Cheat Sheet Search

Search our CompTIA Network+ cheat sheet to find the right cheat for the term you're looking for. Simply enter the term in the search bar and you'll receive the matching cheats available.

About CompTIA Network+

The CompTIA Network+ exam tests your fundamental skills in essential computer networking functions.

You’ll need to answer at most 90 questions in this 90-minute examination and complete a survey after it ends. The passing score is 720 on a scale of 100–900.

The latest CompTIA Security+ exam code is N10-008, available from September 2021 to sometime in 2024. The exam objectives (domains) are as follows:

Domains

This CompTIA Network+ cheat sheet arranges concepts according to our Total Seminars Network+ course subtopics. Diagrams put concepts into a visual form, and tables compartmentalize information. Here’s a key to finding items by domain:

Hashtag (Remember to type the # symbol)	Domain (N10-008)
#nf	Networking Fundamentals
#ni	Network Implementations
#no	Network Operations
#ns	Network Security
#nt	Network Troubleshooting

Network Models

This section lays the foundation for all other Network+ sections.

Domain	Concept	Elaboration
#nf	OSI model	Open Systems Interconnect: 1. Physical 2. Data Link 3. Network 4. Transport 5. Session 6. Presentation 7. Application Memory aid: Please Do Not Throw Sausage Pizza Away
#nf	Unicast/Broadcast	One/All network devices receive data
#nf #ni	DHCP	Dynamic Host Configuration Protocol

Cabling and Topology

Be careful: it’s easy to provide incorrect answers to exam questions related to the different fiber connector types.

Domain	Concept	Elaboration
#nf	Network topology	• Mesh • Star (hub-and-spoke) • Bus • Ring • Hybrid
#nf	TIA/EIA-568A	1. White/green 2. Green 3. White/orange 4. Blue 5. White/blue 6. Orange 7. White/brown 8. Brown
#nf	TIA/EIA-568B	Swap “green” and “orange” in TIA/EIA-568A
#nf	Coaxial	F-type, BNC
#nf	Twinaxial/twinax	Has two inner conductors instead of one as in coaxial
#nf	Twisted pair	RJ-45, RJ-11
#nf	STP/UTP	Shielded/Unshielded twisted pair
#nf	Fiber optic	SC, ST, LC, FC, MT-RJ
#nt	Plenum-rated	Fire-resistant cable; compare with riser-rated, non-plenum rated, and PVC
#nf	Multimode/Single-mode	Cables carry LED/laser signals
#nf	UTP category	Define speed and length of cables: • Cat 3 • Cat 5 • Cat 5e • Cat 6/6a • Cat 7 • Cat 8

Ethernet Basics

Recognizing the Ethernet naming syntax (10Base5, 100Base5, 1000Base5, 10Broad5, 10BaseT, etc.) is crucial to the Network+ exam.

Domain	Concept	Elaboration
#ni #nt	(Auto-)MDI-X	(Automatic) medium dependent interface crossover
#ni #nt	Uplink port	Enable connection between two switches using a straight-through cable
#ni #nt	CSMA/CD	Carrier sense multiple access with collision detection

Ethernet Standards

Familiarize yourself with 1000Base and 10GBase types (names, distances, node numbers, cable types, etc.).

Domain	Concept	Elaboration
#nf	1000BaseT	Maximum cable length: 100m; max speed: 1,000 Mbps (1 Gbps)
#nf	Half-duplex	For one-way communication
#nf	Full-duplex	For simultaneous two-way traffic
#nf	GBIC	Gigabit interface converter
#nf	SFP, SFP+	Small form-factor pluggable
#nf	QSFP	Quad small form-factor pluggable
#ni #nt	Switching/Bridging loop	Two or more data link layer paths between two endpoints
#ni #nt	Layer 2 attack	Attacks on OSI model layer 2 (data link)
#ni #nt	Flood guard	Block malicious traffic from entering a network

Installing a Physical Network

Remember the following concepts in structured cabling:

Domain	Concept	Elaboration
#nf	66-punchdown	Typically used in non-VoIP telephone systems
#nf	110-punchdown	For copper-wired networks
#nf	Fiber distribution panel	For fiber-optic networks
#nt	Wiremap	Simple test to confirm each wire terminates correctly
#nt	TDR	Time domain reflectometer
#nt	OTDR	Optical TDR
#nt	NEXT	Near-end crosstalk
#nt	FEXT	Far-end crosstalk
#nf #ns #no	MDF	Main distribution frame
#nf #ns #no	IDF	Intermediate distribution frame
#nf #ns	U (unit)	Standard height for rack components; 19-inch wide and a multiple of 1¾-inch tall
#nf #ns	Demarc	Separate the telecom company’s property from your responsibility

TCP/IP Basics

Review additional information on IPv4 on your own.

Domain	Concept	Elaboration
#nf #ni	Internet Protocol (IP)	IPv4 and IPv6
#nf #ni	Transmission Control Protocol (TCP)	Connection-oriented
#nf #ni	User Datagram Protocol (UDP)	Connectionless
#nf #ni	IPv4 address	32-bit number, consisting of four decimals from 0 to 255 separated by period (.), e.g., 192.168.1.1
#nf #ni	IPv4 loopback	127.0.0.1
#nf #ni	APIPA/link-local	169.254.x.x
#nf #ni	Classless Inter-Domain Routing (CIDR)	CIDR IPv4 addresses have a prefix; e.g., “/24” in “10.150.23.58/24” denotes a 255.255.255.0 subnet mask.

Routing

Review router-related abbreviations below.

Domain	Concept	Elaboration
#nf #ni	BGP	Border Gateway Protocol
#ni	OSPF	Open Shortest Path First
#ni	RIP	Routing Information Protocol
#nf #ni	MTU	Maximum transmission unit
#nf #ni	IGP/EGP	Interior/Exterior Gateway Protocol
#nf	NAT	Network Address Translation
#nf	PAT	Port Address Translation

TCP/IP Applications

Remember to check out our Common Ports Cheat Sheet.

Domain	Concept	Elaboration
#nf	NTP	Network Time Protocol
#nf	SNTP	Simple Network Time Protocol
#nt	IGMP	Internet Group Management Protocol
#nf #nt	IPAM	IP Address Management
#nt	Networking troubleshooting tools	Windows: tracert Linux: • traceroute • ifconfig • pathping • netstat

Well-known ports: unencrypted vs encrypted

Network Naming

Network administrators cannot skip this section.

Domain	Concept	Elaboration
#nf	DNS	Domain Name System
#nf	SOA	Start of authority
#nf	A/AAAA	DNS record for IPv4/IPv6
#nf	CNAME	Canonical name or alias
#nf	MX	Mail exchange
#nf	PTR	Pointer record

Securing TCP/IP

Review key network security acronyms here.

Domain	Concept	Elaboration
#ns	RADIUS	For authentication, authorization, and accounting
#ns	TACACS+	For access control
#ns	Kerberos	For authentication and authorization on wired networks
#ns	EAP	Extensible Authentication Protocol
#ns	PEAP	Protected Extensible Authentication Protocol
#nt	PKI	Public Key Infrastructure
#ns	SAML	Security Assertion Markup Language

Switch Features

The definition for VLAN (virtual local area network) is in the section Integrating Networked Devices.

Domain	Concept	Elaboration
#ni	VTP	VLAN Trunking Protocol
#ni #ns #nt	STP	Spanning Tree Protocol
#ni #ns #nt	BPDU	Bridge protocol data unit
#ni #no	LACP	Link Aggregation Control Protocol
#ni	QoS	Quality of service
#ni	IDS	Intrusion detection system
#ni	IPS	Intrusion prevention system

IPv6

Here are IPv6 concepts for quick learning:

Domain	Concept	Elaboration
#nf #ni	NDP	Neighbor Discovery Protocol
#nf #ni	IPv6 address	128-bit hexadecimal number, e.g., 2001:7120:0000:8001: 0000:0000:0000:1F10
#nf #ni	IPv6 loopback	::1 (unicast)
#nf	VLSM	Variable-length subnet mask

WAN Connectivity

Review additional information on WAN construction by yourself.

Domain	Concept	Elaboration
#nf #ns	VPN	Virtual Private Network
#nf	WDM/BWDM	Bidirectional wavelength division multiplexing
#nf	DWDM	Dense wavelength division multiplexing
#nf	MPLS	Multiprotocol Label Switching
#ni	GSM	Global System for Mobile Communications
#ni	TDMA	Time-division multiple access
#ni	EDGE	Enhanced Data rates for GSM Evolution
#ni	CDMA	Code-division multiple access
#nf #ns	ICA	Independent Computing Architecture (Citrix)
#nf #ns	TightVNC	Tight Virtual Network Computing
#nf #ns	RDP	Microsoft Remote Desktop Protocol
#nf #ns	PPTP	Point-to-Point Tunneling Protocol
#nf #ns	L2TP/IPsec	Layer 2 Tunneling Protocol over IPsec
#nf #ns	EAP	Encapsulating Security Payload
#nf #ns	GRE	Generic Routing Encapsulation

Wireless Networking

The ubiquity of mobile devices makes mastering wireless networking a necessity.

Domain	Concept	Elaboration
#ni	SSID	Service Set Identifier
#ni	BSSID/ESSID	Basic/Extended Service Set Identifier
#ni	CSMA/CA	Carrier-sense multiple access with collision avoidance
#ni	DSSS	Direct-sequence spread-spectrum
#ni	OFDM	Orthogonal frequency-driven multiplexing
#ni	Wireless Ethernet versions	• 802.11a • 802.11b • 802.11g • (802.11i) • 802.11n • 802.11ac • 802.11ax
#ni	PoE	Power over Ethernet • PoE injector • PoE+ 802.3af, 15.4 watts • PoE+ 802.3at, 30 watts
#ni #nt	Wireless antennae	• Omni • Dipole • Patch • Directional/Yagi • Directional/Parabolic • SMA (SubMiniature version A) connector Gain measured in dBi
#ni	WPA2	Wi-Fi Protected Access version 2, encryption: CCMP-AES
#nt	APIPA	Automatic Private IP Addressing
#ns	Evil twin	Fake Wi-Fi access point to trick people into choosing it over the genuine one

Virtualization and Cloud Computing

This section covers virtual machines and key ideas in cloud computing.

Domain	Concept	Elaboration
#nf	Cloud	Considerations: • Scalability • Elasticity • Multitenancy • Security implications • Principle of least privilege Types: • Public • Private • Community • Hybrid
#nf	Hypervisor Type 1	Bare or native metal
#nf	Hypervisor Type 2	App-like VM on the operating system
#nf	IaaS	Infrastructure as a Service
#nf	PaaS	Platform as a Service
#nf	SaaS	Software as a Service
#nf	DaaS	Desktop as a Service
#nf	VDI	Virtual desktop infrastructure
#nf	IaC	Infrastructure as Code
#nf	vSwitch	Virtual switch
#nf	VPC	Virtual private cloud
#nf	NFV	Network function virtualization
#nf	SDN	Software-defined networking

Data Centers

The prevalence of cloud computing makes learning about data centers a necessity.

Domain	Concept	Elaboration
#nf	FCoE	Fibre Channel over Ethernet
#nf	FC	Fibre Channel
#nf	HBA	Host bus adaptor
#no	FHRP	First Hop Redundancy Protocol
#no	VRRP	Virtual Router Redundancy Protocol
#no	HSRP	Hot Standby Router Protocol
#no	UPS	Uninterruptible power supply
#no	HVAC	Heating, ventilation, and air conditioning
#no	PDU	Power distribution unit

Integrating Networked Devices

Know the differences between every type of “area network.”

Domain	Concept	Elaboration
#ni #ns	IoT	Internet of Things
#nf #ni	VoIP	Voice over IP
#ni	ICS	Industrial control systems
#ni	SCADA	Supervisory control and data acquisition system
#nf #ni	LAN	Local area network
#nf	WLAN	Wireless local area network
#ni	VLAN	Virtual LAN; split one broadcast domain into two
#nf	CAN	Campus area network
#nf	WAN	Wide area network
#nf	SD-WAN	Software-defined wide area network
#nf	MAN	Metropolitan area network
#nf	PAN	Personal area network
#nf	SAN	Storage area network

Network Operations

Network operations cover the actions needed to protect a network and its associated organization. Two main risks are security and business.

Domain	Concept	Elaboration
#no #ns	NDA	Nondisclosure Agreement
#no #ns	MOU	Memorandum of Understanding
#no #ns #nf	MSA	Multi-Source Agreement
#no #ns	SLA	Service Level Agreement
#no #ns	BYOD	Bring Your Own Device
#no #ns	SOW	Statement of Work
#ns	Incident response	• Forensics • First responder • Secure the area • Document the scene • Collect evidence • Chain of custody • Forensics report • Legal hold • Electronic discovery (e-discovery)
#no	RPO	Recovery point objective
#no	RTO	Recovery time objective
#no	MTTR	Mean time to repair
#no	MTTF	Mean time to failure
#no	MTBF	Mean time between failures
#no	BCP	Business continuity plan
#no #nt	AUP	Acceptable use policy
#no #nt	MDM	Mobile Device Manager
#no #nt	COBO	Corporate-owned, business only
#no #nt	COPE	Corporate-owned, personally enabled
#no #nt	CYOD	Choose your own device

Protecting Networks

This is a vital section, especially if you intend to embark on a career in cyber security.

Domain	Concept	Elaboration
#ns	CIA triad	Confidentiality, integrity, availability
#ns	Honeypot/honeynet	Individual/connected devices inviting attacks to capture information
#ns #nt	Rogue DHCP server	IP address is outside of the network ID
#ns	Screened subnet (demilitarized zone, DMZ)	Five components: • External network • External router • Perimeter network • Internal router • Internal network
#ni #ns #nt	Man-in-the-middle (MITM)/on-path attack	Intercept a two-party conversation for one’s advantage. Tools: • Ettercap • Wireshark • tcpdump
#ns	Spoofing	Digital misrepresentation • MAC • IP • VLAN
#ni #ns	DTP	Cisco Dynamic Trunking Protocol
#ns	ITAD	IT asset disposal
#ns	DNS poisoning	Exploit known DNS vulnerabilities
#ns	URL hijacking/typosquatting	Target URL typos
#ns	Replay attack	Intercept data and replay later
#ns	Downgrade attack	Force a network channel to switch to an unprotected or less secure data transmission standard
#ns	Session hijacking	Seize control of a user’s browsing session to gain access
#no #ns	Brute-force attack	Trying character combinations
#no #ns	Dictionary attack	Using lists of probable passwords
#ni #ns	VLAN hopping	Attacker can move from one VLAN to another
#ns	CVE	Common vulnerabilities and exposure: publicly disclosed list of security flaws
#ns	CNA	CVE Numbering Authority
#ns	Zero-day	Flaw discovered by third party sooner than vendor
#ni #ns	DAI	Cisco Dynamic ARP Inspection
#ni #ns	RA	Router Advertisement
#ni #ns	Control plane policing	Use QoS to stop Denial-of-Service attacks
#ni #nt #ns	Firewall	Filter for network traffic. - Hardware/software - Stateful/stateless - Network-based/host-based - Context-/application-aware
#ni #nt	UTM	Unified threat management
#ni	ACL	Access control list
#ni	DPI	Deep-packet inspection
#ns	Virus	Run on a computer without the user’s knowledge. Examples: Boot Sector, Macro, Program, Polymorphic, Stealth, and Multipartite.
#ns	Worm	Replicate itself across a network
#ns	Trojan Horse	Perform useful functions superficially but runs malicious programs covertly
#ns	Spyware	Spy on a computer and record its activities. Examples: keylogger and browser-hijacking adware
#ns	Rootkit	Gain administrator-level access to the system core undetected
#ns	Ransomware	Hold a computer hostage until the user pays
#ns	Adware	Unwanted software displaying advertisements
#ns	Remote Access Trojans (RATs)	Malware to remotely control an infected computer
#ns	Logic bomb	Start a malicious program upon fulfillment of certain logical conditions
#ns	Crypto-malware	Mine cryptocurrency that enriches perpetrators
#ns	Physical controls	• Deterrent: ○ Preventative ○ Detective ○ Corrective • Recovery • Compensating controls

Network Monitoring

Monitoring a network helps nip problems in the bud.

Domain	Concept	Elaboration
#ns	SIEM	Security Information and Event Management
#nf #no #ns	SNMP	Simple Network Management Protocol
#nf #no #ns	NMS	Network management system/station
#no	Event Viewer, Syslog	Tools to display logs

Network Troubleshooting

Apply the six technical troubleshooting steps (same as A+) to networking problems.

Domain	Concept	Elaboration
#nt	Additional considerations on the “establish theory” step	- Top-to-bottom/bottom-to-top - OSI model - Divide and conquer

Technical Troubleshooting Flow Chart — Technical Troubleshooting Best Practice Methodology (borrowed from our A+ Cheat Sheet)

Conclusion

We hope this CompTIA Network+ cheat sheet helps your learning or career journey. Check out our other articles on networking, strictly exam-related test taking tips, and Network+ accelerated certification training programs, which include supplemental sample tests and chapter-end test questions. No matter where you go next, we wish you all the best.

CompTIA Network+ Cert. (N10-008): The Total Course

4.8

★★★★★

CompTIA Network+ Cert. (N10-008): Practice Tests

4.9

★★★★★

Frequently Asked Questions

Is the CompTIA Network+ exam hard?

Yes, it’s challenging although it’s an entry-level certification for IT jobs in computer networking.

Is CCNA harder than Network+?

Yes. CCNA covers highly technical networking specifications. Read our article “Network+ vs CCNA” comparing both.

How many times can you fail the CompTIA Network+ exam?

Countless times. If you fail the first time, you can re-register for the Network+ exam immediately, but you must wait 14 days between future attempts.

Is Network+ or Security+ harder?

Security+ is harder because it’s the next step in the CompTIA Secure Infrastructure Specialist trifecta of A+ > Network+ > Security+ and builds upon the knowledge of Network+.

Is Network+ enough to get a job?

No. Jobs explicitly requiring Network+ are fewer than vendor-specific networking certifications such as CCNA, but many cyber security jobs require Security+, and Network+ preparation will help you study for Security+.

Can I skip A+ and do Network+?

Yes. The Network+ exam has no prerequisites, but A+ is a recommended prequel to it.

How long is Network+ valid?

The Network+ certification is valid for three years. Here’s how to renew it on the CompTIA website.

Can you use Notes on Network+ exam?

No, this is a closed-book exam. If you do so, you’ll lose your CompTIA certifications and ability to take future exams. Read more about CompTIA’s policy on cheating here.

Level Up in Cyber Security: Join Our Membership Today!

MEMBERSHIP

Cassandra Lee

Cassandra is a writer, artist, musician, and technologist who makes connections across disciplines: cyber security, writing/journalism, art/design, music, mathematics, technology, education, psychology, and more. She's been a vocal advocate for girls and women in STEM since the 2010s, having written for Huffington Post, International Mathematical Olympiad 2016, and Ada Lovelace Day, and she's honored to join StationX. You can find Cassandra on LinkedIn and Linktree.