Ch. 4 Ethernet Technology
You have a Layer 2 switch. You have left all ports in the default VLAN. You connect five workstations. How many broadcast domains exist on this switch?
1. By default, there is one broadcast domain on the switch. If you create additional VLANs, this will create additional broadcast domains.
What is the distance limitation of 10GBASE-LW?
10 km
What is the distance limitation of 10GBASE-LR?
10 km. 10GBASE-LR uses single-mode fiber (SMF) as its media type, has a bandwidth capacity of 10 Gbps, and a distance limitation of 10 km. 10GBASE-SW uses multimode fiber (MMF) as its media type, has a bandwidth capacity of 10 Gbps, and a distance limitation of 300 m. 10GBASE-ER and 10GBASE-EW both use single-mode fiber (SMF) as their media type, have a bandwidth capacity of 10 Gbps, and a distance limitation of 40 km. Also, 100GBASE-ER4 uses SMF as its media type, has a bandwidth capacity of 100 Gbps, and a distance limitation of 40 km.
You need to implement a data center for your company. In this data center, you plan to implement inter-rack connections that are limited to 25 meters (82 feet). Which Ethernet standard should you implement?
1000Base-CX. 1000Base-CX is designed for wiring closets. It has a transmission rate of 1,000 Mbps and a maximum segment length of 25 meters (82 feet).100Base-FX is the IEEE standard for a fiber-optic Fast Ethernet network topology. This standard transmits at 100 Mbps over a baseband connection, and uses fiber-optic cable as the transferring medium. It has a maximum segment distance of 2 kilometers (1.24 miles).
You are designing a SOHO network for your company. You want to use the Ethernet standard that supports a data transmission rate of 1 Gbps over copper cable. Which Ethernet standard should you use on the network?
1000BaseCX. The 1000BaseCX Ethernet standard supports a data transmission rate of 1 gigabit per second (Gbps) over 150-ohm balanced copper cable. The 1000BaseCX Ethernet standard supports a maximum cable segment length of only 25 meters (m). The 1000BaseCX Ethernet standard was designed to support connections between network nodes that are in close proximity, such as nodes in a network's wiring closet. The 1000BaseCX standard specifies 8-pin High Speed Serial Data Connectors (HSSDCs) or 9-pin D-subminiature connectors. HSSDC connectors are preferred over the 9-pin D-subminiature connectors because they provide a better electrical connection than the D connectors. Note that 1000BaseCX Ethernet equipment may be difficult to obtain, because it never became popular.
You are looking at implementing several different 10GBase networks. You need to implement the one that offers the longest cable run because of the distances you must cover for your company's network. Which 10GBase specification should you select?
10GBaseER. The 10GBaseER designation allows a maximum cable run of up to 40 kilometers (25 miles) using single-mode fiber optic cable.
You have been hired as a network administrator. The company wants to implement a 10 Gigabit Ethernet designation for use with a SONET network. Which of the following should you implement?
10GBaseSW
What is the maximum amount of power a switch is allowed to provide per port according to the IEEE 802.3af standard?
15.4W
What is the distance limitation of 10GBASE-SW?
300 m. 10GBASE-SW uses multimode fiber (MMF) as its media type, has a bandwidth capacity of 10 Gbps, and a distance limitation of 300 m.
What is the distance limitation of 100GBASE-ER4?
40 km
What is the distance limitation of 10GBASE-ER?
40 km. 10GBASE-ER and 10GBASE-EW each use single-mode fiber (SMF) as their media type, have a bandwidth capacity of 10 Gbps, and a distance limitation of 40 km. Also, 100GBASE-ER4 uses SMF as its media type, has a bandwidth capacity of 100 Gbps, and a distance limitation of 40 km.10GBASE-LW uses single-mode fiber (SMF) as its media type, has a bandwidth capacity of 10 Gbps, and a distance limitation of 10 km.10GBASE-SW uses multimode fiber (MMF) as its media type, has a bandwidth capacity of 10 Gbps, and a distance limitation of 300 m.
You have a Layer 2 switch. You have left all ports in the default VLAN. You connect five workstations. How many collision domains exist on this switch?
5. There is one collision domain for each device connected. Therefore, there are five collision domains.
Which IEEE standard, supported on some Ethernet switches, requires a user to authenticate themselves before gaining access to the rest of the network?
802.1X. The IEEE 802.1X standard specifies a method of enforcing user authentication. For example, a PC (that is, the supplicant) that wishes to gain access to a network via an Ethernet switch (that is, the authenticator) must provide appropriate credentials to a RADIUS server (that is, the authentication server). IEEE 802.3af and IEEE 802.3at are both Power over Ethernet (PoE) standards. IEEE 802.1Q is an Ethernet trunking standard.
What is the IEEE standard for link aggregation?
802.3ad is the open standard version of link aggregation.
What is the IEEE standard for the version of Power over Ethernet that offers a maximum of 15.4 Watts of power to an attached device?
802.3af. Both IEEE 802.3af and IEEE 802.3at are Power over Ethernet (PoE) standards. However, the 802.3af standard specifies a maximum wattage of 15.4 Watts, while the 802.3at standard specifies a maximum wattage of 32.4 Watts. IEEE 802.1Q is an Ethernet trunking standard. IEEE 802.1d is a standard for Spanning Tree Protocol (STP).
What is the IEEE standard for the version of Power over Ethernet that offers a maximum of 32.4 Watts of power to an attached device?
802.3at
Identify the distance limitation of a 1000BASE-T Ethernet network.
A 1000BASE-T Ethernet network features a distance limitation of 100 m.
What is a native VLAN?
A native VLAN is the VLAN on an IEEE 802.1Q trunk that does not have any tag bytes added. An IEEE 802.1Q trunk can simultaneously carry traffic for multiple VLANs. One, and only one, VLAN in a 802.1Q trunk is untagged. Frames belonging to all other VLANs each receive four tag bytes. The name of this untagged VLAN is the native VLAN. All traffic in a 802.1Q trunk is in-band. An EtherChannel virtual port does have a special VLAN type.
What device is used to create many different collision domains, thus helping to eliminate collisions in the modern network?
A switch operates at Layer 2 and functions based on Layer 2 MAC addresses. Switches are designed to create a collision domain for each connected device. This helps to eliminate collisions in the network.
You need to implement an independent network within your private LAN. Only users in the Research and Development department should be able to access the independent network. The solution must be hardware based. Which type of network should you deploy?
A virtual local area network (VLAN). You should deploy a VLAN. This type of network can be used to ensure that internal access to other parts of the network is controlled and restricted. A VLAN is usually created using a switch. VLANs provide a layer of protection against sniffers and can also decrease broadcast traffic. Creating a VLAN is much simpler than using firewalls or implementing a virtual private network (VPN).
Which of the following reflect the media type, bandwidth capacity, and distance limitation combination of 10BASE-T Ethernet?
Cat 3 (or higher) UTP/10 Mbps/100 m. 10BASE-T Ethernet uses Cat 3 (or higher) UTP, has a bandwidth capacity of 10 Mbps, and a distance limitation of 100 m.
Which IEEE 802.1X component checks the credentials of a device wanting to gain access to the network?
Authentication server
Your organization has several VLANs implemented on its network. The VLANs operate across several switches. What do all users on a VLAN have in common?
Broadcast domain. VLANs place users from many locations into the same broadcast domain. A single VLAN can span multiple physical LAN segments, collision domains, and TCP/IP segments. VLANs can be based on work function, common applications or protocols, department, or other logical groupings. VLAN assignment is configured at the switch for each device that is connected to the switch. VLANs enable many users at many locations to be in the same broadcast domain. Remember, routers define broadcast domains, and because switches are Layer 2 devices, they do not segment broadcast domains; instead, they segment collision domains. VLANs span multiple collision domains, subnets, and cable segments, so users would not have these aspects of the network in common. IEEE 802.1Q is the networking standard that supports VLANs on an Ethernet network. Broadcast domains can be created using switches or routers.
Which open standard creates a redundancy group to share an IP address?
CARP. Common Address Redundancy Protocol (CARP) is an open standard that creates a redundancy group to share an IP address.
What is the technology used in an Ethernet network that features a backoff timer?
CSMA/CD. CSMA/CD permits multiple systems on an Ethernet network to communicate. Collisions, if they occur, are detected and systems retransmit. This is different from CSMA/CA, which seeks to avoid collisions altogether. Wireless networks typically feature a CSMA/CA approach and half-duplex communications.
Which of the following reflects the media type, bandwidth capacity, and distance limitation combination of 10BASE2 Ethernet?
Coax/10 Mbps/185 m. 10BASE2 Ethernet (also known as thinnet) uses coax cable, has a bandwidth capacity of 10 Mbps, and a distance limitation of 185 m.
Which of the following reflect the media type, bandwidth capacity, and distance limitation combination of 10BASE5 Ethernet?
Coax/10 Mbps/500 m
In a topology running STP, every network segment has a single ______________ port, which is the port on that segment that is closest to the root bridge in terms of cost.
Designated. The designated port is forwarding, and there must be one on every network segment. Remember, all ports on a root bridge are designated by default.
If two devices simultaneously transmit data on an Ethernet network and a collision occurs, what does each station do in an attempt to resend the data and avoid another collision?
Each device sets a random back-off timer, and the device will attempt retransmission after the timer expires. A random back-off timer is used in the CSMA/CD network once a collision is detected.
Your company has decided to implement either a 1000Base-LX or 1000-Base-SX network. Which type of cable should you use?
Fiber optic
What technology allows devices to simultaneously transmit and receive data?
Full Duplex permits multiple systems on an Ethernet network to communicate simultaneously, avoiding collisions. Each port on a layer 2 switch that is operating in Full Duplex mode has a 1 pair of wires for sending, and another pair for receiving, which allows collision avoidance.
You have been asked to create several TIA/EIA 568A wiring cables for your network. Which color wire should be placed in Pin 1?
Green/White.
Which of the following standards specifies a method for sending traffic for multiple VLANs across a single link?
IEEE 802.1Q. A trunk is a single connection (either physical or logical (for example, an EtherChannel connection)) that can simultaneously carry traffic for multiple VLANs. A popular Ethernet trunking standard is IEEE 802.1Q (also known as "dot 1Q").
Your network uses a single switch that divides your network into three virtual LANs (VLANs). The devices in each VLAN are connected to a single port on the switch. You plan to implement a second switch on your network. You need to ensure that the VLANs that were originally implemented are spread across both switches. What should you do?
Implement frame tagging on both switches. You need to implement frame tagging on both switches to ensure that the VLANs that were originally implemented are spread across both switches. Tagging is a technique that adds a small header to the frame as it is passed between devices in order to maintain the original VLAN broadcast domain. In normal Ethernet, there is no tagging. Tagging is implemented only when trunking VLANs between devices is involved. If you only have one switch, an untagged VLAN is just fine. If you have two or more switches and you want all of the VLANs to talk with each other, they will all need the same tag. You should not create a port-based, protocol-based, or subnet-based VLAN on both switches. The original switch is already configured to use port-based switching. Port-based switching alone will not ensure that the VLANs that were originally implemented are spread across both switches. Neither will protocol-based or subnet-based switching.
Your network contains several virtual LANs (VLANs). What is a benefit of using this technology?
It allows networks to be segmented logically without being physically rewired. A virtual LAN (VLAN) is a networking technology that allows networks to be segmented logically without having to be physically rewired. In a traditional Ethernet network, you can replace all hubs with VLAN switches. This creates virtual network segments whose logical topology is independent of the physical topology of the wiring. Each station is assigned a VLAN identification number (ID), and stations with the same VLAN ID function as though they are all on the same physical network segment, no matter which physical switch they are connected to. Only devices with the same VLAN ID will receive broadcasts sent by a host. The assignment of VLAN IDs is done at the port level on the switches themselves. Moving a host to another department only requires the assignment of a different VLAN ID to the port on the switch to which the host is connected. No rewiring of cables is necessary. The primary benefit of having a VLAN is that users can be grouped together according to their need for network communication, regardless of their actual physical locations. Membership in a VLAN segment, called a VLAN group, is controlled by the network management software, which allows users to be grouped according to their needs.
You have decided to implement 802.1q. What does this standard do?
It implements VLAN trunking. If you implement 802.1q, you are implementing VLAN trunking. It allows traffic from all VLAN to cross a single cable between two switches. If 802.1q were not implemented, each separate VLAN would require its own port connection. Trunking (802.1q) allows different switches to support the same virtual LAN (VLAN) using frame-tagging. For example, when two ports on Switch A are connected to one port on Switch B, trunking has been implemented. Frame tags will be used to route the communication appropriately. If you need to add a switch to a room through which laptops can connect for full network access, you should configure a trunk on a switch port for both switches, including the new switch in the room and the switch to which the new switch connects. The 802.1d standard implements Spanning Tree Protocol (STP), which prevents looping.MAC filtering allows traffic to be permitted or denied based on the device's MAC address. MAC filtering is just one type of traffic filtering that you can configure on devices. You can also configure traffic filtering based on other criteria, such as device name or port used. Quality of Service (QoS) forwards traffic based on pre-configured priorities.
You want to enable port authentication on your network switches. On which setting is port authentication based?
MAC address. 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.
What kind of media is used by 100GBASE-SR10 Ethernet?
MMF. Multi-Mode Fiber.
While troubleshooting a network outage on a 10GBaseSW network, a technician finds a 500-meter fiber cable with a small service loop and suspects it might be the cause of the outage. Which of the following is most likely the issue?
Maximum cable length exceeded. On a 10GBaseSW network, the maximum cable length is 300 meters. A 10GBaseSW network uses multi-mode fiber cable.
What name is given to a VLAN on an IEEE 802.1Q trunk whose frames are not tagged?
Native VLAN. The 802.1Q native VLAN is the only VLAN in the Layer 2 domain that is not tagged.
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.
You are installing the wiring for a small office. You want to connect the fifty computers in the office to the switch. The Cat6 cables that you plan to use have RJ-45 connectors on both ends. Which component should you use?
Patch panel
What switch feature allows you to connect a network sniffer to a switch port and tells the switch to send a copy of frames seen on one port out the port to which your network sniffer is connected?
Port mirroring. Port mirroring permits frame analysis in a switched network.
Which Ethernet switch feature allows an Ethernet switch to provide power to an attached device?
Power over Ethernet (PoE) allows an Ethernet switch to provide power to an attached device (for example, an IP phone or a wireless access point).
You are implementing several switches on your network. The network contains client computers that run both Internet Protocol (IP) and Internetwork Packet Exchange (IPX). To increase network efficiency, you need to configure the switches so that the two different types of traffic are isolated. Which type of virtual local area network (VLAN) should you implement?
Protocol-based VLAN.
For a branch office network deployment, you have been asked to select network switches for the wiring center in your office building. You need a solution that does not rely on the availability of wall outlets to plug in IP-attached surveillance cameras, IP phones, and wireless access points near the RJ-45 wall jacks where those devices will be attached to the network. Which of the following options within a switch will solve this problem?
PoE. Power over Ethernet (PoE), also known as in-line power, allows a network switch to provide power to network-attached devices, including video surveillance cameras, IP phones, and wireless access points (WAPs), through the wall jack that delivers an Ethernet connection. This relieves network designers of the need to ensure adequate power outlets where they wish to stage network devices. While switches usually provide configuration files (or data) for most common devices they are likely to service, including cameras, phones, and WAPs, this has nothing to do with relieving the network designer of concerns about the proximity or availability of a power outlet. This only helps you to have easy access to the configuration files. While most modern switches provide a Web-based UI for setup, configuration, monitoring, and management, this has nothing to do with relieving the network designer of concerns about the proximity or availability of a power outlet. This only ensures that you can remotely manage the switch settings. Because network switches usually run 24/7/365, they can incur very high bills for electricity consumption. Green, energy efficient fanless chassis help to alleviate some of the power cost concerns. Buyers are paying increasing attention to energy efficiency and eco-friendliness. However, cost efficiency will not relieve the network designer of concerns about the proximity or availability of a power outlet. Quality of Service (QoS) support means that a switch can prioritize traffic. This allows important or time-sensitive traffic to get through faster and less important or time-insensitive traffic to get through when it can. QoS can be important on networks with real-time or time-sensitive traffic such as VoIP (voice) or streaming media. However, this will not relieve the network designer of concerns about the proximity or availability of a power outlet.
What Ethernet switch feature allows a PC running packet capture software and connected to one switch port to receive a copy of traffic seen on another switch port?
Port mirroring is a feature that makes a copy of traffic seen on one port and sends that duplicated traffic out another port (to which a network sniffer could be attached).
Which Ethernet switch feature allows an Ethernet switch to make a copy of frames seen on one switch port and send those copies out of another Ethernet switch port? (NOTE: This feature is often used to allow a network analyzer connected to one switch port to see traffic present on a different switch port.)
Port mirroring. Port mirroring allows an Ethernet switch to make a copy of frames seen on one switch port and send those copies out of another Ethernet switch port, to which a network analyzer might be attached.
You need to copy the traffic from a single port to a different port, but prevent bidirectional traffic on the port. Which switch feature should you use?
Port mirroring. Port mirroring copies the traffic from a single port to a different or mirror port, but prevents bidirectional traffic on the port. It allows you to view all of the traffic for a single VLAN, no matter the switch where the traffic originates. Local port mirroring only uses ports from the same switch. Remote port mirroring uses ports from multiple switches.
You have decided to implement frame tagging in a port-based switching network. What does this technique ensure?
That a single VLAN can be distributed across multiple switches.
Your company's networking team wants to deploy 10 Gbps Ethernet (10GbE) over fiber optic cables for its core or backbone network segments. Which of the following types of transceivers are they most likely to plug directly into their switches, routers, and server network adapters?
SFP+. They are most likely to plug an SFP+ transceiver into their switches, routers, and server network adapters. As data rates increase to 10 Gbps and beyond, networks make increasing use of fiber optic cables to convey the signals necessary to encode and transport the huge volumes of information involved. Likewise, fiber optic cable is a must for long-haul communications and for distances over 1 km for cable runs. A fiber optic transceiver acts to convert digital data into pulses of light for transmission, and to convert those pulses of light into digital data upon reception. A variety of fiber optic transceiver types can support 10GbE, but only one of them is currently widely deployed and used for that purpose in equipment from vendors that include Cisco, Aruba (HPE), Juniper, Dell and so forth. This is the plus version of the small form-factor pluggable (SFP+) fiber optic transceiver.
You need to deploy a fiber distribution panel offer for datacenter, remote office, or local area networking use. Which of the following features are not important for such uses?
Support for SFP+ and for GBIC connectors is not important for such uses. These two options represent connectors used at endpoints, such as routers, switches, and network interfaces, not connectors or functions present in FDPs themselves. GBIC connectors are used for end-point termination at a device interface of some kind. They are neither typically used nor necessary on a fiber distribution panel. SFP+ stands for the enhanced, or plus, version of the small form-factor (hot) pluggable (or SFP) fiber optic connector. Such connectors are used for endpoint connections, not in FDPs where no optical-to-digital or digital-to-optical conversion need necessarily occur. A fiber distribution panel (FDP), also known as a fiber optic distribution panel, offers the following for datacenter, remote office, or local area networking use: Cable termination: FDPs usually provide a common point for terminating fiber optic cables so that they may be connected to fiber optic terminal equipment, such as switches, routers, and network interfaces of all kinds. Bulkhead adapters and receptacles: In an FDP, distribution pigtails with their single connectors (the other end will be spliced to another fiber optic cable coming either from off or on the current premises) are routed through cable distribution trays or cable management trays and will be terminated in bulkhead adapters and attendant receptacles. Cable splices: FDPs provide facilities for mounting and protecting fiber optic cable splices, including clamps and mounts to secure spliced cables. They may also include one or more splice trays, where spliced cross- or pass-through fiber optic connections may be stored. Splice trays also usually house the splice chips used to create necessary fiber optic cable splices on location. Cable storage: FDPs usually include cable reels for storing pigtails and patch cables, and may include other cable storage space and options as well. Often, splice tray(s) and extra cable storage is provided at the bottom of an FDP chassis. FDPs offer fiber optic cable management, cable routing, and cable control for high-density fiber optic deployments. In particular, FDPs generally provide space for fiber optic cable termination, fiber optic cable storage (for pigtails and patch cables), fiber optic cable splices (up into the hundreds, depending on the specific FDP under consideration or in use), and access to bulkhead adapters and receptacles for fiber optic cables.
You are implementing a SOHO network for a small business. The business owner has asked that you implement a 1 gigabit per second (Gbps) network. Which Ethernet standard specifies a data transfer rate of 1 Gbps?
The 1000BaseT Gigabit Ethernet standard specifies a maximum data transfer rate of 1 Gbps. Category 5 unshielded twisted-pair (CAT5 UTP) cable and RJ-45 connectors are typically used on 1000BaseT Ethernet networks.
You are setting up your company's VoIP infrastructure. One remote office location has audio problems when placing or receiving calls. At times, speech quality is poor, or there is a noticeable and distinct echo for call audio. In troubleshooting a possible system configuration issue, which of the following possibilities do you want to eliminate first?
The call terminates on an analog endpoint. You should first determine whether the call terminates on an analog endpoint. Dealing with audio quality issues on Voice over Internet Protocol (VoIP) is an occasional necessity. But before digging into the usual troubleshooting routine, it is essential to establish if the problem call or connection terminates on VoIP equipment on both sides. If one end of a call terminates on an analog endpoint, occasional audio problems are inevitable. Non-VoIP equipment cannot provide routine compression, echo cancellation, and sound quality enhancements. When a call terminates on an analog endpoint, this is really nothing to troubleshoot (aside from replacing the analog endpoint). So that possibility should be eliminated first before troubleshooting commences. All of the other steps should be verified after you ensure that both endpoints are VoIP, not analog. If echo cancellation is misconfigured or not enabled, echoes are far more likely on VoIP calls. But these two steps apply only if the call is VoIP from end-to-end. Ideally, both ends of a VoIP call should use the same compression mode settings, because that offers the best assurance for the highest possible signal quality. The H.323 protocol is the most widely used protocol for packet voice communications. Its selection versus other voice protocols, such as SIP, does not significantly affect call quality and echo one way or other. On any kind of software system, checking to make sure updates have been applied is a time-honored best practice for system management. However, such updates may have nothing to do with call quality if one end of the call terminates on an analog endpoint.
A system on an Ethernet network detects a collision. How does it respond?
The device retransmits after waiting for a period dictated by the backoff timer. After a collision is detected in a CSMA/CD network, the device will resend the traffic. It will do so after waiting for a time period dictated by the backoff timer. There is no attempt to contact the other station directly, nor is there any central mediator. The frame that is re-sent is the original frame.
You are deploying fiber optic links and connections on a local area network. You need to ensure proper and efficient data communications. Which transceiver or fiber optics characteristics are essential?
The following transceiver or fiber optics characteristics are essential: 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 hundreds of meters) and are well-suited for LAN applications. Full duplex: Full-duplex communications means that both parties may transmit and receive simultaneously over a communications link. Because LAN applications require simultaneous, two-way communications, full duplex is needed. Duplex cables: 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, this supports simultaneous, two-way communications and is well-suited for LAN applications.
What device in an STP domain features all ports in a Designated state?
The root bridge is the root of the spanning-tree domain. All of its ports are forwarding and in the Designated state. All other options here do not exist in STP.
You have been hired as the network administrator. The company's network consists of several subnetworks located in various locations across the southeast United States. You want to deploy switches across the different locations so that you can implement virtual local area networks (VLANs). What is the primary benefit of this implementation?
Users can be grouped by their work functions, by shared applications or protocols, or by department, regardless of their geographical location. VLANs place users from many locations into the same broadcast domain. A single VLAN can span multiple physical LAN segments. VLANs can be based on work function, common applications or protocols, departments, or other logical groupings. An example of a work function VLAN would be grouping all executives into the same broadcast domain. The three main benefits of VLANs are security, segmentation, and flexibility. Flexibility and segmentation are important because today's networking environment is no longer limited to a single location. With multiple district, branch, and home offices, traditional LANs are very inefficient. VLANs address these issues by allowing users to be grouped by functions, common applications, departments, and various other logical groupings. However, whichever criterion you use to group VLANs, you should be consistent throughout the network. VLANs improve security by controlling broadcasts and forcing upper-layer security checks so that all devices cannot communicate using Layer 2 alone. A VLAN's primary purpose is not to provide micro-segmentation for a single geographic location. VLANs do not provide switchless networking using virtual addresses, and VLANs can be grouped by multiple criteria, not just by their physical location. Note that each switch port is assigned to a single VLAN.
Which Ethernet switch feature allows you to create a VLAN on one switch and have that VLAN be automatically created on other switches?
VLAN Trunking Protocol (VTP) is a Cisco-proprietary Ethernet switch feature that allows you to create, modify, or delete a VLAN on one switch and have that change propagated to all other switches in a VTP domain.
You have been hired as a network administrator for a large corporation. This network includes a large number of switches that must be identically configured. In the past, this information has been configured manually. You want to automatically propagate the VLAN information to all switches on the LAN. What should you use?
VTP, 802.1q. To automatically propagate VLAN information to all switches on the LAN, you should use VLAN Trunking Protocol (VTP), which is also referred to as 802.1q. VTP configuration will prevent the VLAN information from having to be manually configured on all of the switches. VTP allows two switches to share VLAN information.
You need to implement Spanning Tree Protocol (STP) to prevent network loops when more than one path can be used. Which two devices could you deploy?
You could deploy bridges or switches, which use STP to prevent loops in the network when more than one path can be used. STP uses the Spanning Tree Algorithm (STA) to help a switch or bridge by allowing only one active path at a time. STP can prevent network congestion and broadcast storms. Routers and hubs do not use STP. There are two types of STP: spanning tree (802.1d) and rapid spanning tree (802.1w). 802.1d is an older standard that was designed when a minute or more of lost connectivity was considered acceptable downtime. In Layer 3 switching, switching now competes with routed solutions where protocols such as Open Shortest Path First (OSPF) and Enhanced Interior Gateway Routing Protocol (EIGRP) provide an alternate path in less time. You can implement a layer 3 switch and virtual LANs (VLANs) to limit the amount of broadcast traffic on a network and allow different segments to communicate with each other. The 802.1w protocol was developed to improve performance. 802.1w bridges are fully distributed, while 802.1d switches agree on a root port. This root port acts differently than the other switches and is responsible for the network's connectivity.802.1w defines roles for the ports and a new bridge protocol data unit (BPDU) format, which introduces the proposal/agreement mechanism. BPDU's handling and convergence is different in each protocol. 802.1w introduces these new features: Rapid Transition To Forwarding State - includes new Edge Ports and Link Types variables. Uplink Fast - distinguishes between port roles and uses alternate ports. By default, unknown unicast and multicast traffic is flooded to all Layer 2 ports in a VLAN. This unknown traffic flooding can be prevented by blocking unicast or multicast traffic on the switch ports. However, keep in mind that there may be times when you need to use unicast or multicast traffic. You can also configure forwarding and blocking on a switch port. If you configure forwarding, certain types of traffic based on the rules you configure will be forwarded to a certain port. If you configure blocking, certain types of traffic can be blocked from a switch port. For the Network+ exam, you also need to understand Link Aggregation Control Protocol (LACP), also referred to as 802.3ad. LACP supports automatic link configuration and prevents an individual link from becoming a single point of failure. With this protocol, traffic is forwarded to a different link if a link fails. You can manually or automatically assign the IP address for the switch. Automatic configuration uses a DHCP server to obtain the IP address and all other information that you have configured the DHCP server to assign. The DHCP server does not have to be on the same subnetwork as the switch. If you manually configure the IP address, you need to ensure that all settings are correct. Switches should be given their own IP address and default gateway to use so that they can be remotely managed. For IP address assignment for devices attached to the switch, some switches can also be configured to act as a DHCP server and assign IP addresses to attached devices. However, you must ensure that the DHCP ranges configured on the switch do not overlap the ranges configured on other DHCP servers. Otherwise, you may have a single IP address assigned to multiple hosts on the network, thereby affecting communication. For switches, you also need to understand Power over Ethernet (PoE), Defined by the IEEE 802.3af and 802.3at standards. PoE allows an Ethernet switch to provide power to an attached device by applying power to the same wires in a UTP cable that are used to transmit and receive data. PoE+ is an enhanced version of PoE that provides more power and better reliability. PoE+ is most commonly deployed in enterprise networks, while PoE is usually sufficient for small business or home networks.
You are wiring a small office for a client. The client has purchased several 568A and 568B wall jacks and enough 568A wiring cables to attach all devices correctly. You want to configure the network for ease of administration.
You should use only 568A wall jacks. Both the 568A and 568B wiring specifications will work for a network configuration. However, you must use the same specification throughout your network. Because the client has purchased enough 568A wiring cables to attach all devices correctly, you should choose to use the 568A wiring scheme.
What media type is used by 10GBASE-SR?
multimode fiber (MMF)
What media type is used by 1000BASE-ZX?
single-mode fiber (SMF)