CompTIA NETWORK + STUDY GUIDE
NETWORK + STUDY GUIDE
This "guide" (dump) was constructed through many attempts at practice exams, and each question I missed I made note of the correct info in this following list.
Each 1-? numbered list are the details I needed to review more after each practice exam attempt. Reading this list through before an exam attempt was helpful and I did eventually pass and get my Network + cert lol.
I definitely recommend making your own list using the method above when studying.
- Adhoc mode - computers can access each other but not other network resources - LAN, WAN, internet…
- wireless range extenders - use for small home/office layout with no more than 10 devices but with two dead spots
- 802.11a - provides the most non-overlapping channels (eight) and the shortest range
- Users report they cannot upload files to new file server - check ACL settings and blocked TCP/UDP ports
- 10GBaseER allows highest maximum cable run of up to 40km using single-mode fiber optic cable
- EAP-TLS = Extensible Authentication Protocol with Transport Layer Security authentication supports client-side digital certificates for auth with access points
- Phishing / e-mail hoax is a social engineering attack
- 802.11a uses 5GHz frequency band
- The protocols use the following ports
- port 20 = FTP ( it also uses port 21 )
- 23 = Telnet
- 25 = SMTP
- 53 = DNS
- 80 = HTTP
- SSH = 22
- DHCP = 67,68
- TFTP = 69
- POP3 = 110
- NTP = 123
- NetBIOS = 139
- IMAP = 143
- SNMP = 161
- LDAP = 389
- HTTPS = 443
- SMB = 445 or 139
- LDAPS = 636
- H.323 = 1720
- MGCP = 2427/2727
- RDP = 3389
- RTP = 5004/5005
- SIP = 5060/5061
- 10.0.0.0 through 10.255.255.255
- 172.16.0.0 through 172.31.255.255
- 192.168.0.0 - 192.168.255.255
- Physical network diagram - includes cable lengths , types, server names, IP address, server roles, network equipment locations, and number of users
- Network baseline - includes performance stats for the network
- APIPA - fe80::/10
- Private - fc00::/7
- Loopback ::1/128
- Bridges and switches operate at the data link layer
- Release and renew the DHCP lease for client computer:
- ipconfig /release
- ipconfig /renew
- establish if other users are having the same problem
- Coaxial cables have two conductors - the inner is covered by insulation
- Virus - is a malicious software that relies upon other application programs to execute and infect a system
- VLANs place users from many locations into the same broadcast domain
- You should implement Split Horizon to prevent routing loops
- Water or soda acid should be used to suppress a fire that has wood products and paper
- CompTIA password guidelines -
- create passwords that contain at least one symbol
- configure passwords to change periodically
- Class A Public - 188.8.131.52
- Class A Private - 10.6.55.44
- Class B Public - 184.108.40.206
- Class B Private - 172.20.5.5
- Class C Public - 220.127.116.11
- Class C Private - 192.168.103.213
- APIPA - 169.254.43.31
- APIPA assigns a class B IP address from 169.254. 0.0 to 169.254. 255.255 to the client when a DHCP server is either permanently or temporarily unavailable.
- Cable Certifier - used to collect network cable test data and print certification reports
- Cable Tester - used to test cable resistance levels but does not locate faults
- Multimeter - electronic measuring tool that tests voltage, current, and resistance
- OTDR - Optical Time Domain Reflectometer - used to check fiber cable resistance and locate faults
- Protocol Analyzer - used to capture and analyze data sent over a network
- TDR - Time Domain Reflector - used to check UTP/STP cable resistance and locate cable faults
- Tone Generator/ probe - used to identify and trace wires
- The IP address size increases from 32 to 128 bits
- Some of the header fields have been dropped
- Version 6 has less rigid length limits and the ability to introduce new options
- Packets will indicate a particular traffic type
- Support will be provided for data integrity and confidentiality
- The IPv6 header is 40 fixed bytes and has eight fields of information
- Host A → Switch → Host B
- allocate two networks with /22 masks, and the remaining four with /23
- first physical barrier against intruder - fence
- Valid reasons to assign a virtual IP address to an internet server
- To permit the same address to access multiple domain names
- To permit multiple servers to share the same address
- to eliminate host dependencies on specific, individual network interfaces
- To reduce congestion by decreasing network traffic
- to increase network security
- ex. College kids connecting personal devices between classes causing congestion
- 110 block supports higher frequencies than a 66 block
- requires less space
- supports both telephone & data ( 66 is only used on telephone networks)
- Use IPSec to secure RDP over the Internet with connection security rules and associations
- You cannot use 802.11a access points with 802.11b or 802.11g
- In a situation where IPsec is needed end-to-end only IPv6 makes sense as a solution
- Valid reasons for upgrading from IPv4 to IPv6
- Routing traffic is increasingly difficult due to the rapid growth of the internet
- IPv4 addresses are being depleted at an increasing rate
- 802.11g APs only have 3 non-overlapping channels (1,6,11 -US ) (1,6,13 -EU)
- Pin 1 on 568B spec should contain the Orange/White wire
- Remove leading zeros
- remove consecutive fields of zeros with double colon
- The double colon (::) can only be used once
- CAT 1 - up to 4 Mbps
- CAT 2 - 4
- CAT 3 - 10
- CAT 4 - 16
- CAT 5 - 100
- CAT 5e - 1000 Mbps or 1GB
- CAT 6 - 1000 Mbps
- CAT 6a - 10Gbps
- CAT 7 - 10Gbps
- 20 & 21 - FTP
- 110 - POP3
- 143 - IMAP
- 443 - HTTPS
- 3389 - RDP
- A crossover cable connects two legacy or non-MDIX compliant devices such as two computers, two hubs, or two switches
- A patch cable and a straight through cable are the same thing - this is the standard cable used to connect network devices
- configure the default gateway address as 18.104.22.168/24
- IPSec uses encapsulation security payload (ESP) and authentication header (AH) as security protocols for encapsulation
- can work in either tunnel mode or transport mode
- used in a virtual private network (VPN) implementation to secure transmissions
- network baseline
- physical network diagram
- It will NOT affect the logical network diagram or the wiring schematic
- SFP (small form-factor pluggable) works with SONET, GbE, Fibre Channel but will NOT work with 10GbE
- router ___ switch ___ host A
- ^__ host B
- Host A will send an ARP request for Host B’s MAC address
- Host A will send a frame with the destination MAC address of Host B
- The switch will forward the frame to Host B
- Disable device ports
- Disable unnecessary services
- Bus network ex. ( straight line all connected end to end )
- user1 — user2 — user3 — serverA — user4 — user5
- 22.214.171.124/18 is an example of a ‘slash x’ network
- with 18 bits used. The standard subnet mask is 11111111.11111111.11000000.00000000 or 255.255.192.0
- Shared authentication and open authentication were the two insecure methods of authentication under WEP. Under Shared Key Authentication (SKA) all clients used the same key making it very vulnerable to being cracked
- You instruct a user to issue the ifconfig command /release /renew options. Which situations would this be appropriate for?
- When recent scope changes have been made on the DHCP server
- When it has been issued an APIPA address
- Install another WAP that uses a different non-overlapping channel and the same SSID so the connections will be distributed
- Least Privilege
- Need to Know
- A - Maps a host name to an IPv4 address
- AAAA - Maps a host name to an IPv6 address
- CNAME - Maps an additional host name to an existing host record
- MX - Maps a mail server name to a domain
- PTR - ( pointer record ) Maps an IP address to a host name
- Physical layer - Network cable
- Data Link layer - FDDI (fiber distributed data interface)
- Network Layer - IPSec
- Transport Layer - TCP
- Session Layer - RPC (remote procedure call)
- Presentation - MIME (multipurpose internet mail extension)
- Application - DHCP
- 1000Base-TX transmits 500 Mbps and requires more expensive Cat6 copper cabling
- Also configure each router as a scope option for it’s appropriate scope. Each scope will have a different router or default gateway. For this reason router or default gateway info must be configured at the scope level
- You should be most concerned with Channel Overlap in this case
- Cat5 - Up to 100m and 100Mbps
- Cat6 - Up to 100m and 10Gbps
- Multi-mode fiber - up to 500m and 10Gbps
- Single-mode fiber - up to 40Km and 10Gbps
- ThickNet - up to 500m and 10 Mbps and uses RG-6 coaxial cabling
- ThinNet - up to 185m and 10 Mbps and uses RG-59 coaxial cabling
- eliminates host dependencies on specific , individual network interfaces
- permits multiple servers to share the same address
- permits the same address to access multiple domain names
- bits 3,5,6,8 are on
- 128, 64, 32, 16, 8 , 4 , 2 , 1
- 32 + 8 + 4 + 1 = 45
- Class A - 126.96.36.199
- Class B - 188.8.131.52
- Class C - 184.108.40.206
- APIPA - 169.254.1.1
- Private - 172.16.2.3
- Loopback - 127.0.0.1
- Multicast - 255.47.72.63
- Private address spaces
- The most likely valid reason for moving servers that contain confidential information onto a demilitarized zone (DMZ) is compliance with federal and state regulations
- Security guard personnel are the most expensive countermeasure used to reduce physical security risks. The cost of hiring, training, and maintaining them can easily outweigh the benefits
- Common Address Redundancy protocol (CARP) is an open standard that creates a redundancy group to share an IP address
- To avoid multipath distortion you should use the diversity antenna system.
- Multipath distortion is caused by the reflection of radio frequency (RF) signal on surfaces while traveling between the transmitter and receiver
- subnet: 172.16.4.0, broadcast: 172.16.5.255
- Port Address Translation (PAT) provides port address translation. This is based on port numbers
- Port authentication on your network switches is based on the switch’s MAC address. If the switch is not specifically configured with a MAC address the MAC address communication is not allowed through the switch port.
- 100Base-TX, known as Fast Ethernet, uses two pairs of CAT5 UTP cable, standard RJ-45 connectors are used. 100Base-TX transmits data at 100Mbps with a maximum segment distance of 100meters
- T1 lines can provide fast, digital connections of up to 1.544 Mbps, transmitting voice, data, and video. T1 line also provides a dedicated connection, which means it provides a 24hr link.
- 1000BaseCX Ethernet standard supports a data transmission rate of 1 gigabit per second over 150-ohm balanced copper cable. 1000BaseCX ethernet standard supports a max cable length of only 25meters
- A Unified Threat Management (UTM) appliance would be the best device to provide multiple security functions in a central location. UTM appliances incorporate multiple security and performance functions in one device.
- You should use channels 36-48 and 149-161 for indoor and outdoor wifi use. All 802.11n and 802.11ac client devices support use on these two bands.
- channels 52-64 are reserved for government weather radar systems
- channels 100-144 are also reserved for gov weather radar systems
- cable termination
- cable splices
- bulkhead adapters and receptacles
- cable storage
- 802.11a - 5Ghz up to 54 Mbps
- 802.11b - 2.4Ghz up to 11 Mbps
- 802.11g - 2.4Ghz up to 54 Mbps
- 802.11n - 2.4 or 5Ghz up to 600 Mbps
- 802.11g and b are backwards compatible
- 802.11ac - 5Ghz up to 1Gbs (good for streaming video to multiple devices)
- the reserved client options take precedence over all other options
- The order in which options are applied are as follows:
- server options
- scope options
- class options
- reserved client options
- Scope options always override server options if there is a conflict. Class options always override scope and server options. To use class options, DHCP clients must be configured with a specific DHCP Class ID. Reserved client options always override client, scope, and server options.
- Multimode - multimode cable makes use of thicker, graded light-conducting fibers that are cheaper to make and terminate, and that use cheaper and less precise light emitting and receiving elements in their transceivers. They are more limited in the distances such cables can span ( but can still cover 100s of meters) and are well suited for LAN applications
- Full duplex - communications means that both parties may transmit and receive simultaneously over a communications link. Because LAN applications require simultaneous, two-way comms, full duplex is needed
- Duplex cables - incorporate two fibers so that one may be used to send data for receipt by another party, while that other party may use the other fiber to send data for receipt by the first party, thus supports simultaneous, two-way comms and is well suited for LAN applications.
- Tagging and untagging ports
- to expand the network
- to reduce congestion
- to reduce CPU use
- to isolate network problems
- to improve security
- to allow combos of media because each subnet can support a diff medium
- You should deploy media converters between the wiring centers on each floor - if the media /cabling is dissimilar
- In both the (TIA) / (EIA) 568A and 568B specifications - Pins 4,5,7, and 8 contain the same colors.
- 568A Pin 1 = Green/white
- 568B Pin 1 = Orange/white
- The Forward lookup Zone is most likely to contain the IP address if Computer A is trying to communicate with Computer B but only knows Computer B’s FQDN (fully qualified domain name / whatever.somesite.org)
- An MAU is similar to a HUB and also operates on the Physical layer of the OSI model
- Asset tags can include RFID chips that provide electronic tracking
- Active Hubs or multiport repeaters amplify or regenerate signals to all other ports on the hub. All hubs operate on the Physical layer of the OSI model.
- Once a solution or workaround has been implemented the next step is to TEST the solution to be sure the problem is resolved. Later document the problem and the solution.
- Legacy systems would be best isolated on a separate network segment to reduce the attack surface by limiting it to only specific users.
- You have replaced all of the routers on your network with switches. You then decide to turn off CSMA/CD. What is the BEST description of the result of your actions?
- - Network devices will now operate in full-duplex mode. Because each switch port is connected to a single device and each device operates in its own collision domain, you can turn off CSMA/CD, thereby allowing full-duplex mode, meaning that traffic can be transmitted in both directions at the same time.
- After a client is authenticated on a network that uses Kerberos 5, the client is granted a ticket-granting ticket (TGT). To ensure that tickets expire correctly, clock synchronization used in Kerberos authentication. In Kerberos, a client is granted a TGT from an Authentication Server (AS), which is sometimes referred to as a ticket granting Server (TGS). The client then sends its TGT to a Key Distribution Center (KDC), and the KDC sends a session key to the client. The client then uses the session key to gain access to resources on a Kerberos network. Because the KDC relies on a timestamp to determine the age of a request, a timestamp is included during key exchanges. If the timestamp is older than the allowed grace period for requests, then it is possible that a hacker intercepted the request. Therefore, a network that relies on Kerberos for authentication requires some type of time synchronization service for hosts on a network.
- IMAP (Internet Message Access Protocol / version 4 = IMAP4) is an internet protocol for email retrieval that uses TCP port 143. IMAP works at the Application layer of the OSI model.
- Transceiver mismatch occurs when you have a fiber connector plugged into the wrong type fiber port. ex. Do not plug in SFP into an SFP+ port bc it won’t work.
- 802.11n WAP has a max distance of 230ft which is more than 802.11ac in which the max is only 115ft. Ordinarily 802.11ac would be the best choice for deployment because of its ability to support multiple simultaneous users, wide data channels, and higher data rates - but distance and cost limitations may call for 802.11n to be used instead.
- You should implement a virtual SAN (vSAN) if - you need to isolate two of the devices that are located on a SAN fabric containing 8 devices for example.
- 802.11a WLAN technology supports 23 non-overlapping or non-interfering channels that can be used in a single area.
- MPLS VPN - To allow all offices to connect to the same single-routed network and connect directly to the cloud - The best solution is to deploy a Multiprotocol Label Switching Layer 3 (MPLS L3) Virtual private network (vpn).
- To view the MAC address for a NIC installed on a Windows 7 computer use the following command
- - ipconfig /all
- MTBF - mean time between failures - will allow you to schedule replacement of a component at a convenient time as opposed to waiting for it to fail.
- - MTTR - mean time to recover - is the avg time it takes to recover or restore a system.
- A Wiring Schematic - includes the flow of network communication and symbols to indicate equipment function. They use horizontal and vertical lines to show how the system flow functions, not the physical layout of the devices on the network.
- - A Wiring Diagram - emphasizes network connections and uses horizontal and vertical lines to represent network wires. Components are represented by pictures instead of symbols.
- A Physical Network Diagram includes the actual network interfaces used. It represents the physical locations of the network devices and how they are connected. Can be used to determine the actual network interfaces used on all network devices.
- The netstat command displays incoming and outgoing connections, routing tables, and network interface statistics. Refer to netstat when documenting current network connections.
- The advantage of wireless bridges over E1/T1 lines is that wireless bridges support higher bandwidth than E1/T1 lines, and E1/T1 lines tend to be more expensive in the long term.
- IEEE 802.11 wireless LANs use a media access control protocol called Carrier Sense Multiple Access with Collision Avoidance (CSMA/CA). While the name is similar to Ethernet's Carrier Sense Multiple Access with Collision Detection (CSMA/CD), the operating concept is totally different.
- 802.11g devices are incompatible with 802.11a networks.
- - 802.11g devices are compatible with 802.11b networks
- - 802.11n networks allow the usage of 802.11a, 802.11b, and 802.11g devices
- A Quarantine Network should be set up in an office for devices that do NOT comply with the network access control (NAC) policies.
- Reasons to assign a virtual IP address to an Internet server
- - to permit multiple servers to share the same address
- - to eliminate host dependencies on specific, individual network interfaces
- - to permit the same address to access multiple domain names
- Class of Service (CoS) implements packet tagging in a local area network (LAN). It tags the different types of traffic, such as video streaming or VoIP.
- Deploy a VLAN if you need to implement an independent network within your private LAN
- SSL is assigned to the same port as HTTPS - Port 443
- You manage a network for your organization. The network contains one DNS server and three routers. You are setting up a new DHCP server.
You configure separate scopes for each subnet on your network. The routers are configured to forward DHCP requests. You need to ensure that DHCP clients receive the appropriate settings using the least administrative effort. What else should you do?
- - You should configure the DNS server as a server option. This will ensure that all DHCP clients receive the DNS server settings
- -You should also configure each router as a scope option for its appropriate scope. Each scope will have a different router or default gateway. For this reason, router or default gateway information must be configured at the scope level. If you configure this option at the server level, all the clients would receive the same router configuration, which would not work because you have three different subnets.
- ESD ( electrostatic discharge ) has most likely caused the network interface card (NIC) to malfunction if you know it was good but you see a spark when installing…
- In a situation where IPsec is needed end-to-end only IPv6 makes sense
- IPv6 Relative Network Sizes
1 IPv6 address
A network interface
1 IPv6 subnet
18,446,744,073,709,551,616 IPv6 addresses
256 LAN segments
Popular prefix size for one subscriber site
65,536 LAN segments
Popular prefix size for one subscriber site
65,536 /48 subscriber sites
Minimum IPv6 allocation
16,777,216 subscriber sites
256 times larger than the minimum IPv6 allocation
- The most significant difference between Data Link layer addresses and Network addresses is that network addresses are a network layer component (layer 3) and Data Link addresses are MAC addresses (Layer 2) used for unique identification.
- A bridge provides a quick and low-cost solution for dividing a network into different segments for the purposes of reducing network traffic. Bridges work by building routing tables based on MAC addresses. These routing tables enable bridges to determine which packets need to pass through the bridge to another segment, versus which packets should stay on the local segment. In this scenario, the Accounting department is currently sharing the bandwidth of the entire segment. Using a bridge to place this department on its own segment means the traffic of this segment will stay on the local segment, thus reducing the overall traffic of the network. Only packets destined for other segments will pass through the bridge.
- Training employees about proper licensing and use of an organization’s software and hardware includes the following:
- - To prevent unauthorized or improper consumption of licenses
- - To avoid liability from violating license rules or restrictions
- - To comply with license restrictions or limitations
- - To practice good organizational ethics and governance
- Which of the following are relevant to network segmentation when using switches?
- - VLANs
- - Tagging and untagging ports
- ~ ARP tables and MAC tables are NOT relevant to network segmentation
- Dual stack to the rescue.
ISPs have chosen an IP address transition method called dual stack. With the dual stack solution, every networking device, server, switch, router and firewall in an ISP's network will be configured with both IPv4 and IPv6 connectivity capabilities.