Cisco CCST 100-150 Networking Practice Exam

• A. Session layer
• B. Network layer Correct answer
• C. Data Link layer
• D. Transport layer

Option B, Network layer, is correct because it is the OSI layer responsible for logical (IP) addressing and determining the best path to route packets between different networks. Option C, the Data Link layer, handles local delivery using physical (MAC) addressing rather than routing between networks. Options C and D, Transport and Session, deal with end-to-end communication and dialogue control, not path selection.

• A. Network Access (Link) layer Correct answer
• B. Application layer
• C. Transport layer
• D. Internet layer

Option A, the Network Access (Link) layer, is correct because the four-layer TCP/IP model condenses the OSI model's Physical and Data Link layers into this single layer. Option D, the Internet layer, corresponds to the OSI Network layer instead. Options B and D correspond to the OSI Transport and Application layers respectively, not the combined Physical/Data Link functions.

• A. Packet - Network layer Correct answer
• B. Bit - Application layer
• C. Frame - Data Link layer Correct answer
• D. Segment - Physical layer

Options A and B are correct because Frame is the Data Link layer's protocol data unit and Packet is the Network layer's protocol data unit, both properly paired. Option D incorrectly pairs Segment with the Physical layer, when Segment actually belongs to the Transport layer. Option B incorrectly pairs Bit with the Application layer, when Bit is actually the Physical layer's unit.

• A. PC2
• B. SW2
• C. SW1
• D. R1 Correct answer

Option D, R1, is correct because it is the only device that sits between Site A and Site B, so it must examine the destination IP address to forward traffic between the two subnets. SW1 and SW2 only forward within their own site by MAC address, and PC2 is an end host, not a forwarding device.

• A. 203.0.113.0/24
• B. 8.8.8.0/24
• C. 1.1.1.0/24
• D. 192.168.0.0/16 Correct answer

Option D, 192.168.0.0/16, is correct because it is one of the RFC 1918 private address ranges reserved for internal use and not routable on the public internet. Options B, C, and D are all publicly routable address blocks, including well-known public DNS/documentation ranges, not private space.

• A. To assign MAC addresses to devices
• B. To resolve domain names to IP addresses
• C. To encrypt traffic between hosts
• D. To translate private IP addresses to a public IP address for internet access Correct answer

Option D is correct because NAT's primary purpose is translating private, internal IP addresses to a public address so devices can access the internet. Option C, encryption, is a separate function NAT does not perform. Options C and D describe MAC address assignment and DNS resolution, unrelated to NAT's address translation role.

• A. 10.0.0.0/8 Correct answer
• B. 172.32.0.0/12
• C. 192.168.0.0/16 Correct answer
• D. 11.0.0.0/8

Options A and B are correct because 10.0.0.0/8 and 192.168.0.0/16 are both valid private IPv4 ranges defined by RFC 1918. Option B, 172.32.0.0/12, falls outside the actual private range, which only spans 172.16.0.0 through 172.31.255.255. Option D, 11.0.0.0/8, is a publicly routable range, not one of the RFC 1918 private blocks.

• A. 192.168.1.1
• B. 192.168.1.10
• C. 203.0.113.1
• D. 203.0.113.5 Correct answer

Option D, 203.0.113.5, is correct because that is R1's outside interface address, and NAT translates PC1's private 192.168.1.10 source address to this public address before the traffic leaves the office for the Internet. R1's inside address (192.168.1.1) and PC1's own address are private and never appear as the source once traffic crosses onto the public Internet.

• A. SC
• B. RJ-11
• C. BNC
• D. RJ-45 Correct answer

Option D, RJ-45, is correct because it is the standard connector used to terminate twisted-pair copper Ethernet cabling. Option B, RJ-11, is used for telephone lines instead. Options C and D, BNC and SC, are used for coaxial and fiber optic connections respectively, not twisted-pair copper.

• A. RJ-45
• B. RJ-11 Correct answer
• C. LC
• D. F-type

Option B, RJ-11, is correct because it is the standard connector used to terminate traditional telephone lines. Option A, RJ-45, is used for Ethernet networking instead. Options C and D, LC and F-type, are fiber and coaxial connectors, neither used for telephone lines.

• A. PC1 to SW1
• B. None of these links
• C. R1 to ISP1 Correct answer
• D. SW1 to R1

Option C, R1 to ISP1, is correct because that link's description, a glass strand carrying signal 8 km, is a description of fiber-optic cabling, which uses fiber connectors rather than the RJ-45 connector used on the copper links shown elsewhere in the exhibit. The PC1-SW1 and SW1-R1 links are both explicitly described as copper, so they use RJ-45 connectors instead.

• A. Uplink Ethernet port
• B. Console port Correct answer
• C. USB storage port
• D. SFP port

Option B, Console port, is correct because it is specifically designed for out-of-band initial device configuration and management, independent of the network data path. Option C, a USB storage port, is used for loading files, not initial configuration access. Options C and D, uplink Ethernet and SFP ports, carry network data traffic rather than serving as the dedicated management access point.

• A. A DNS server
• B. The default gateway Correct answer
• C. The DHCP server
• D. An NTP server

Option B, The default gateway, is correct because a host sends traffic destined for networks outside its own subnet to its default gateway, typically a router interface, for forwarding. Option A, a DNS server, resolves names to addresses but doesn't forward traffic. Options C and D, DHCP and NTP servers, handle address assignment and time synchronization, neither routing traffic to other networks.

• A. 10.1.20.1
• B. 10.1.10.26
• C. 10.1.10.1 Correct answer
• D. 10.1.20.10

Option C, 10.1.10.1, is correct because that is SW1's interface address on PC1's own subnet, which is exactly what a device configures as its default gateway. Option A (10.1.20.1) belongs to R1's other interface on SRV1's subnet, Option D (10.1.20.10) is SRV1 itself, and Option B (10.1.10.26) is PC2's address, none of which PC1 can use as its own gateway.

• A. .log only
• B. .json
• C. .docx
• D. .pcap Correct answer

Option D, .pcap, is correct because it is the commonly used file extension for saved Wireshark packet captures. Options B and C, .docx and .json, are unrelated document and data formats, not used for packet captures. Option A, .log only, describes a different, more generic logging format, not the standard packet capture extension.

• A. ipconfig
• B. nslookup
• C. netstat
• D. ping Correct answer

Option D, ping, is correct because it uses ICMP echo requests and replies to test basic reachability to a remote host. Option B, nslookup, performs DNS name resolution, not reachability testing. Options C and D, netstat and ipconfig, show connection statistics and local IP configuration, neither testing remote host reachability.

• A. The technician's personal opinion of the user
• B. The user's unrelated past support history with other departments
• C. The steps taken and their results Correct answer
• D. A clear description of the reported symptom Correct answer

Options A and B are correct because a clear description of the reported symptom and the steps taken along with their results are both core elements of effective help desk documentation. Option A, a technician's personal opinion of the user, is inappropriate and unprofessional, not a documentation best practice. Option B, unrelated past support history with other departments, is irrelevant clutter that doesn't belong in documentation of the current issue.

• A. Confidentiality, Installation, and Auditing
• B. Confidentiality, Integrity, and Availability Correct answer
• C. Connectivity, Identity, and Authentication
• D. Capacity, Integrity, and Access

Option B, Confidentiality, Integrity, and Availability, is correct because these three properties together make up the foundational CIA triad in security. Option C lists unrelated terms not forming this recognized security model. Options C and D mix in unrelated or fabricated terms, capacity and installation, that aren't part of the actual CIA triad.

• A. DHCP relay
• B. VLAN trunking
• C. Phishing Correct answer
• D. NTP synchronization

Option C, Phishing, is correct because it specifically describes malicious emails that impersonate a trustworthy source to trick users into revealing sensitive information. Options B, C, and D describe unrelated networking protocols, NTP synchronization, DHCP relay, and VLAN trunking, none of which involve deceptive social engineering attacks.

• A. Denying traffic that matches a block rule Correct answer
• B. Assigning DHCP leases to hosts
• C. Resolving DNS queries
• D. Permitting traffic that matches an allow rule Correct answer

Options A and B are correct because permitting traffic matching an allow rule, and denying traffic matching a block rule, are both core functions performed by a firewall. Option B, assigning DHCP leases, is a DHCP server function, not a firewall's role. Option C, resolving DNS queries, is a DNS server function, also unrelated to firewall filtering.