1.3 Identifying Collision and Broadcast Domains

A. Hubs operate on the Physical Layer as they have no intelligence and send all traffic in all directions.

A _____________ is an example of a device that operates only at the physical layer. A. Hub B. Switch C. Router D. Bridge

Transport = End-to-end connection Network = Routing Data Link = Framing Physical = Conversion to bits

Match the OSI model layer definition on the left to its description on the right. Layer Description Transport Routing Physical End-to-end connection Data Link Conversion to bits Network Framing

Transport = Segment Network = Packet Data Link = Frame Physical = Bits

Match the OSI model layer to its Protocol Data Unit (PDU). OSI Layer PDU Transport Bits Data Link Segment Physical Packet Network Frame

C. Switches create separate collision domains within a single broadcast domain. Routers provide a separate broadcast domain for each interface.

Switches break up ____________ domains, and routers break up ____________domains. A. broadcast, broadcast B. collision, collision C. collision, broadcast D. broadcast, collision

C. Replacing the hub with a switch would reduce collisions and re-transmissions, which would have the most impact on reducing congestion.

The most effective way to mitigate congestion on a LAN would be to______________. A. Upgrade the network cards B. Change the cabling to CAT 6 C. Replace the hubs with switches D. Upgrade the CPUs in the routers

C. Wireless AP's are very popular today and will be going away about the same time that rock n' roll does. The idea behind these devices (which are layer 2 bridge devices) is to connect wireless products to the wired Ethernet network. The wireless AP will create a single collision domain and is typically its own dedicated broadcast domain as well.

What is a function of an access point (AP)? A. To monitor and control the incoming and outgoing network traffic B. To automatically handle the configuration of wireless access point C. To allow wireless devices to connect to a wired network D. To connect networks and intelligently choose the best paths between networks

B. Wireless LAN Controllers are used to manage anywhere from a few access points to thousands. The AP's are completely managed from the controller and are considered lightweight or dumb AP's as they have no configuration on the AP itself.

What is a function of the WLAN Controller? A. To monitor and control the incoming and outgoing network traffic B. To automatically handle the configuration of wireless access points C. To allow wireless devices to connect to a wired network D. To connect networks and intelligently choose the best paths between networks

C. Firewalls are used to connect our trusted internal network such as the DMZ, to the untrusted outside network—typically the internet.

What is the function of a firewall? A. To automatically handle the configuration of wireless access points B. To allow wireless devices to connect to a wired network C. To monitor and control the incoming and outgoing network traffic D. To connect networks and intelligently choose the best paths between networks

D. The Application layer is responsible for identifying and establishing the availability of the intended communication partner and determining whether sufficient resources for the intended communication exist.

Which layer in the OSI reference model is responsible for determining the availability of the receiving program and checking to see whether enough resources exist for that communication? A. Transport B. Network C. Presentation D. Application

A. The Transport layer segments data into smaller pieces for transport. Each segment is assigned a sequence number so that the receiving device can reassemble the data on arrival. D. The Network layer (layer 3) has two key responsibilities. First, this layer controls the logical addressing of devices. Second, the Network layer determines the best path to a particular destination network and routes the data appropriately.

Which of the following correctly describe steps in the OSI data encapsulation process? (Choose two.) A. The Transport layer divides a data stream into segments and may add reliability and flow control information. B. The Data Link layer adds physical source and destination addresses and an FCS to the segment. C. Packets are created when the Network layer encapsulates a frame with source and destination host addresses and protocol-related control information. D. Packets are created when the Network layer adds layer 3 addresses and control information to a segment. E. The Presentation layer translates bits into voltages for transmission across the physical link.

C. While it is true that the OSI model's primary purpose is to allow different vendors' networks to inter-operate, there is no requirement that vendors follow the model.

Which of the following is not a benefit of using a reference model? A. It divides the network communication process into smaller and simpler components. B. It encourages industry standardization. C. It enforces consistency across vendors. D. It allows various types of network hardware and software to communicate.

A. The following network devices operate at all seven layers of the OSI model: network management stations (NMSs), gateways (not default gateways), servers, and network hosts.

Which of the following is the only device that operates at all layers of the OSI model? A. Network host B. Switch C. Router D. Bridge

A. The top three layers define how the applications within the end stations will communicate with each other as well as with users.

Which of the following layers of the OSI model is not involved in defining how the applications within the end stations will communicate with each other as well as with users? A. Transport B. Application C. Presentation D. Session

C. The IEEE Ethernet Data Link layer has two sub-layers, the Media Access Control (MAC) layer and the Logical Link Control (LLC) layer.

Which of the following layers of the OSI model was later subdivided into two layers? A. Presentation B. Transport C. Data Link D. Physical

A. Routers by default do NOT forward broadcasts.

Which of the following statements is not true with regard to routers? A. They forward broadcasts by default. B. They can filter the network based on Network layer information. C. They perform path selection. D. They perform packet switching.

B. The contents of a protocol data unit (PDU) depend on the PDU because they are created in a specific order and their contents are based on that order. A packet will contain IP addresses but not MAC addresses because MAC addresses are not present until the PDU becomes a frame.

With respect to the OSI model, which one of the following is the correct statement about Protocol Data Units (PDUs)? A. A segment contains IP addresses. B. A packet contains IP addresses. C. A segment contains MAC addresses. D. A packet contains MAC addresses.

C. You should select a router to connect the two groups. When computers are in different subnets, as these two groups are, you will require a device that can make decisions based on IP addresses. Routers operate at layer 3 of the Open Systems Interconnect (OSI) model and make data-forwarding decisions based on layer 3 networking information, which are IP addresses. They create routing tables that guide them in forwarding traffic out of the proper interface to the proper subnet.

You are the Cisco administrator for your company. A new branch office is opening and you are selecting the necessary hardware to support the network. There will be two groups of computers, each organized by department. The Sales group computers will be assigned IP addresses ranging from 192.168.1.2 to 192.168.1.50. The Accounting group will be assigned IP addresses ranging from 10.0.0.2 to 10.0.0.50. What type of device should you select to connect the two groups of computers so that data communication can occur? A. Hub B. Switch C. Router D. Bridge

B. You should use a switch to accomplish the task in this scenario. A switch is used to provide dedicated bandwidth to each node by eliminating the possibility of collisions on the switch port where the node resides. Switches work at layer 2 in the Open Systems Interconnection (OSI) model and perform the function of separating collision domains.

You need to provide network connectivity to 150 client computers that will reside in the same subnetwork, and each client computer must be allocated dedicated bandwidth. Which device should you use to accomplish the task? A. Hub B. Switch C. Router D. Bridge