1.
A repeater operates at which layer of the OSI reference model?
Correct Answer
A. pHysical
Explanation
A repeater operates at the physical layer of the OSI reference model. The physical layer is responsible for transmitting raw bit streams over a physical medium, such as cables or wireless signals. A repeater receives the signals, amplifies them, and then retransmits them to extend the distance of the network. It does not interpret or modify the data in any way, making it a purely physical device.
2.
The Point-to-Point Tunneling Protocol was developed by which company?
Correct Answer
C. Microsoft
Explanation
The correct answer is Microsoft because the Point-to-Point Tunneling Protocol (PPTP) was indeed developed by Microsoft. PPTP is a network protocol that allows the secure transfer of data between remote clients and a private network over the internet. It was introduced by Microsoft in the 1990s as a part of their Windows operating systems. PPTP became widely used for creating VPNs (Virtual Private Networks) due to its simplicity and compatibility with various platforms.
3.
Which OSI reference model layer is responsible for data encryption?
Correct Answer
D. Presentation
Explanation
The Presentation layer of the OSI reference model is responsible for data encryption. This layer is responsible for formatting, encrypting, and compressing data to be sent across a network. Encryption ensures that data is secure and cannot be easily intercepted or accessed by unauthorized parties. Therefore, the Presentation layer is the correct layer for data encryption.
4.
Which form of ISDN provides bandwidth comparable to T1?
Correct Answer
A. PRI
Explanation
PRI (Primary Rate Interface) is a form of ISDN (Integrated Services Digital Network) that provides bandwidth comparable to T1. PRI is a digital telecommunications interface that allows for the transmission of voice, data, and video over traditional copper telephone lines. It consists of 23 B (Bearer) channels and 1 D (Data) channel, which together provide a total bandwidth of 1.544 Mbps, similar to the bandwidth of a T1 line. BRI (Basic Rate Interface) provides a lower bandwidth of 128 Kbps, while FRI and ASDI are not forms of ISDN.
5.
What is the D channel used for in ISDN networks?
Correct Answer
D. Out Of Band Signaling
Explanation
The D channel in ISDN networks is used for out-of-band signaling. This means that it is responsible for carrying control and signaling information between the user equipment and the network. It is used to establish and tear down calls, as well as to exchange information about call features and capabilities. The D channel operates separately from the B channels, which are used for actual data transfer. By using out-of-band signaling, the D channel ensures efficient and reliable communication between the user and the network.
6.
"Well-known port numbers" are assigned in what range, as specified in RFC 1060?
Correct Answer
A. 0-1023
Explanation
The well-known port numbers are assigned in the range of 0-1023 as specified in RFC 1060. These port numbers are commonly used by protocols and services that are widely recognized and standardized. They are reserved for specific purposes such as HTTP (port 80), FTP (port 21), and SSH (port 22), among others. This range is carefully regulated to ensure that these important services are consistently assigned and easily identifiable across different network devices and applications.
7.
Which of the following is not a Spanning-Tree Protocol port state?
Correct Answer
B. Reading
Explanation
The term "Reading" is not a valid Spanning-Tree Protocol (STP) port state. STP is a network protocol that prevents loops in Ethernet networks by creating a loop-free logical topology. The valid STP port states are Learning, Forwarding, and Blocking. The Learning state allows the port to learn MAC addresses, the Forwarding state allows the port to forward frames, and the Blocking state blocks the port from forwarding frames. Therefore, "Reading" is not a recognized STP port state.
8.
What protocol in the TCP/IP protocol suite is responsible for internetwork routing?
Correct Answer
A. IP
Explanation
The correct answer is IP. IP (Internet Protocol) is responsible for internetwork routing in the TCP/IP protocol suite. It is a network layer protocol that provides the addressing and routing mechanism for data packets to be transmitted across different networks. IP ensures that data packets are correctly routed from the source to the destination network by using IP addresses to identify the source and destination hosts. It also handles fragmentation and reassembly of data packets if they exceed the maximum transmission unit (MTU) size of a network.
9.
In a Class B IP address, how many octets are assigned to network addresses?
Correct Answer
C. 2
Explanation
In a Class B IP address, 2 octets are assigned to network addresses. Class B addresses have a default subnet mask of 255.255.0.0, which means that the first two octets are used to identify the network, while the last two octets are used to identify the host within that network. This allows for a large number of possible networks, as Class B addresses have a range of 16,384 networks.
10.
Which routing protocol is proprietary to Cisco Systems?
Correct Answer
B. EIGRP
Explanation
EIGRP (Enhanced Interior Gateway Routing Protocol) is a routing protocol that is proprietary to Cisco Systems. It is an advanced distance vector protocol that allows routers to exchange routing information and make efficient routing decisions. EIGRP provides fast convergence, load balancing, and supports multiple network protocols. It is widely used in Cisco networks and is not interoperable with other routing protocols, making it exclusive to Cisco devices.
11.
The first published RFC standardized which protocol in 1969?
Correct Answer
A. Network Control Protocol (NCP)
Explanation
In 1969, the first published RFC standardized the Network Control Protocol (NCP). NCP was the original protocol used in the early days of the ARPANET, the precursor to the modern internet. It was responsible for managing connections and providing basic error control for data transmission. However, NCP was later replaced by the Internet Protocol (IP) and the Transmission Control Protocol (TCP), which are still widely used today.
12.
Which company introduced the Token Ring networking technology in 1985?
Correct Answer
C. IBM
Explanation
IBM introduced the Token Ring networking technology in 1985. Token Ring was a local area network (LAN) technology that used a token passing mechanism to regulate access to the network. It was developed as an alternative to Ethernet and offered advantages such as deterministic performance and high reliability. IBM's introduction of Token Ring played a significant role in shaping the LAN industry during that time.
13.
An OC-48 network provides for what speed data transmission?
Correct Answer
C. 2.488 Gbps
Explanation
An OC-48 network provides a data transmission speed of 2.488 Gbps.
14.
What is loosely defined as a set of rules governing network communications?
Correct Answer
D. Protocols
Explanation
Protocols are a set of rules that govern network communications. They define the format, timing, sequencing, and error control of data transmission between devices in a network. Protocols ensure that data is transmitted accurately and efficiently, allowing devices to communicate and exchange information effectively. The other options, such as the Orange Book, Wide Area Network, and Baud Rate, are not directly related to the set of rules governing network communications.
15.
Where did the name 3Com come from?
Correct Answer
B. COMputer COMmunication COMpatibility
Explanation
The name 3Com comes from the combination of the words "COMputer" and "COMmunication" with "COMpatibility." This suggests that the company specializes in providing computer communication solutions that are compatible with various systems and technologies.
16.
Which company introduced the first commercially available modem?
Correct Answer
C. AT&T
Explanation
AT&T introduced the first commercially available modem. A modem is a device that converts digital information into analog signals that can be transmitted over telephone lines. AT&T's introduction of the modem revolutionized communication by allowing computers to connect to the internet and exchange data over long distances. This breakthrough technology paved the way for the widespread adoption of the internet and the development of modern telecommunications systems.
17.
A network frame sent to the MAC address of FF-FF-FF-FF-FF-FF is known as?
Correct Answer
B. A Broadcast Frame
Explanation
A network frame sent to the MAC address of FF-FF-FF-FF-FF-FF is known as a broadcast frame. In a broadcast frame, the destination address is set to FF-FF-FF-FF-FF-FF, which indicates that the frame should be received by all devices on the network. This type of frame is commonly used to send messages or data to all devices within a network, allowing for efficient communication and dissemination of information.
18.
A TCP/IP packet with a destination address of 255.255.255.255 is known as what?
Correct Answer
C. A Broadcast Packet
Explanation
A TCP/IP packet with a destination address of 255.255.255.255 is known as a broadcast packet. In a broadcast, the packet is sent to all devices on the network, allowing the sender to reach multiple recipients simultaneously. The destination address 255.255.255.255 is the broadcast address, which represents all devices on the network. Therefore, a TCP/IP packet with this destination address is considered a broadcast packet.
19.
Which of the following is a circuit-switched service?
Correct Answer
A. TelepHone (POTS)
Explanation
A circuit-switched service refers to a type of communication network where a dedicated physical connection is established between the sender and receiver for the duration of the communication session. In this case, the correct answer is Telephone (POTS) which stands for Plain Old Telephone Service. POTS utilizes circuit-switching to establish a direct connection between two telephone devices, allowing for real-time voice communication. This is in contrast to packet-switched services like ATM, leased lines, and LAN, where data is divided into packets and sent over a shared network.
20.
What is the name of a telco switching facility?
Correct Answer
D. Central Office
Explanation
A telco switching facility is commonly known as a Central Office. It is a location where telephone lines are connected and switched to allow communication between different phone lines. It serves as a hub for telephone exchanges and provides various services such as routing calls, managing connections, and providing access to other telecommunication networks.