220-1201 Questions Bank

Network jitter is variation in the amount of time packets take to reach their destination. Real-time video and audio applications require packets to arrive at relatively consistent intervals.

When jitter becomes excessive, video packets may arrive late or out of sequence. The videoconferencing application may temporarily run out of usable video data, causing the displayed image to freeze. When sufficient packets arrive again, the video resumes.

High bandwidth generally improves the ability to carry video traffic.

Port flapping means a network switch port repeatedly transitions between up and down states. It can cause intermittent connectivity, but a temporary freeze followed by recovery is more directly associated with jitter.

Low latency is desirable because it means packets are delivered with little delay.

CompTIA objective 5.5 explicitly identifies jitter as a common network troubleshooting symptom. Cisco also states that network impairments such as jitter, delay, and packet loss can negatively affect videoconferencing quality.

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An MX, or Mail Exchanger, record is a type of DNS resource record. It identifies the mail server responsible for accepting email for a particular domain. Consequently, an MX record is created or modified in the domain’s DNS zone , which is hosted on a DNS server.

Although the MX record points to a mail server, the record itself is configured through DNS. The mail server is the destination identified by the record, not the service in which the DNS record is stored.

A proxy server intermediates network requests, commonly for filtering, caching, or privacy.

A mail server sends, receives, and stores email, but DNS tells other systems how to locate it.

A print server manages printers and print jobs.

CompTIA objective 2.4 specifically includes DNS record types such as A, AAAA, CNAME, MX, and TXT. Microsoft also defines an MX record as a DNS resource record that identifies a domain’s mail server.

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In CompTIA A+ Core 1 (220-1201) cloud concepts, the key differentiator between cloud deployment models is where the service is hosted and who owns/uses the underlying infrastructure. If a company’s directory services server (for example, a domain controller providing authentication/authorization and centralized identity management) is located on premises, that points to infrastructure that is owned and operated by the organization for its own internal use. This aligns best with a private cloud model, which is defined as cloud resources dedicated to a single organization and can be implemented on-premises (internally hosted) or in a dedicated off-site environment.

It is not a public cloud because public cloud services are hosted by a third-party provider and shared across multiple customers. It is not hybrid cloud because hybrid requires a mix of on-prem resources and public cloud resources working together (the question only specifies on-prem). It is not community cloud because that involves shared infrastructure among multiple organizations with common needs.

A router is a network device that forwards data between different networks by examining packet headers, specifically the IP address information contained in Layer 3 (Network Layer) of the OSI model. According to the CompTIA A+ Core 1 (220-1201) networking objectives, routers use routing tables and packet header analysis to determine the best path for data to travel from a source network to a destination network. When a packet arrives at a router interface, the router reads the destination IP address in the packet header, compares it against its routing table, and then forwards the packet to the appropriate next hop or network interface. This function allows routers to connect multiple networks such as LANs, WANs, and the internet.

The other options do not perform this function. A hub operates at Layer 1 (Physical Layer) and simply broadcasts incoming signals to all connected ports without inspecting any packet information. A repeater also operates at the physical layer and is used only to regenerate or amplify signals to extend network distance. An unmanaged switch operates mainly at Layer 2 (Data Link Layer) and forwards frames based on MAC addresses, not IP packet headers. Because only routers analyze packet headers and forward traffic between different networks, Router is the correct answer.