CNT 125 Chapter 11

traffic shaping

-Delaying less-important traffic -Increasing the priority of more-important traffic

traffic policing

-Limiting the volume of traffic flowing in to or out of an interface during a specified time period -Limiting the momentary throughput rate for an interface

Generator

A _________ serves as a backup power source, providing power redundancy in the event of a total blackout. ____________ can be powered by diesel, liquid propane gas, natural gas, or steam.

standby

A __________ UPS provides continuous voltage to a device by switching virtually instantaneously to the battery when it detects a loss of power from the wall outlet. Upon restoration of power, the ___________ UPS switches the device back to AC power. The problem with a _________ UPS is that, in the brief amount of time it takes the UPS to discover that power from the wall outlet has faltered, a device may have already detected the power loss and shut down or restarted.

protocol analyzer

A _________________, can monitor traffic at a specific interface between a server or client and the network.

network monitor

A __________________ is a tool that continually monitors network traffic.

blackout

A complete power loss.

jabber

A device that handles electrical signals improperly - device always re-transmitting (bad NIC or electrical interference)

DC

A flashlight, uses ______. The batteries in a flashlight have positive and negative poles, and the current always flows at a steady rate in the same direction between those poles,

brownout

A momentary decrease in voltage; also known as a sag. An overtaxed electrical system can be the cause.

surge

A momentary increase in voltage due to lightning strikes, solar flares, or electrical problems.

FCoE

A newer technology that allows FC to travel over Ethernet hardware and connections. FC frame is encapsulated inside an ______ frame, which is then encapsulated inside an Ethernet frame

online

An __________ UPS uses the AC power from the wall outlet to continuously charge its battery, while providing power to a network device through its battery. In other words, a server connected to an __________ UPS always relies on the UPS battery for its electricity.

disaster

An extreme type of incident, involving a network outage that affects more than a single system or limited group of users.

incident

Any event, large or small, that has adverse effects on a network's availability or resources. This could be a security breach, such as a hacker gaining access to a user's account, an infection, such as a worm or virus, or an environmental issue, such as a fire or flood.

managed device

Any network node monitored by the NMS- each object is assigned an OID

SNMP

Application layer protocol that communicates data between the managed device (the agent) and the management console (NMS)

differential backup

Backs up data that has changed since the last full backup

full backup

Backs up everything every time a backup is done

incremental backup

Backs up only data that has changed since the last backup

HSRP

CARP is a free alternative to VRRP (Virtual Router Redundancy Protocol), or Cisco's propriety version called _________. Although VRRP and _______ function somewhat differently than CARP and are used solely for routers, the general idea is the same.

Hot Site

Computers, devices, and connectivity necessary to rebuild a network exist, and all are appropriately configured, updated, and connected to match your network's current state.

Cold Site

Computers, devices, and connectivity necessary to rebuild a network exist, but they are not appropriately configured, updated, or connected.

Warm Site

Computers, devices, and connectivity necessary to rebuild a network exist, with some pieces appropriately configured, updated, or connected.

RAID 1

Data is mirrored—or duplicated—on multiple disks to provide fault tolerance. If one copy is lost, the other copy is still available.

RAID 5

Data is striped across three or more drives, and parity information is added to the data. Parity checking can be used to recreate data from any one drive if that drive fails, even though only one copy of the data is stored.

RAID 0

Data is striped—or written across—multiple disks to improve performance. Provides no real redundancy, in that only one copy of data is stored.

noise

Fluctuation in voltage levels caused by other devices on the network or EMI.

LACP

For multiple NICs or ports to use link aggregation, they must be properly configured in each device's operating system. _______ dynamically coordinates communications between hosts on aggregated connections, kind of like what DHCP does for IP addressing.

promiscuous

In __________ mode, also called monitoring mode, a device driver directs the NIC to pass all frames to the operating system and on to the monitoring software, not just those broadcast or intended for the host.

availability

In the world of networking, the term _____________ refers to how consistently and reliably a connection, system, or other network resource can be accessed by authorized personnel. It's often expressed as a percentage, such as 98% or 99.5%.

in-line monitoring

Install a device, called a network TAP (test access point) or packet sniffer, in line with network traffic.

IB

Like FC, requires specialized network hardware. It's very fast, _____ tends to serve a few niche markets rather than being widely available. ________ falls on the difficult end of the installation and configuration spectrum, and runs on the expensive side as well.

port mirroring

Program a switch to use ________, whereby all traffic sent to any port on the switch is copied to this specified port

wireless monitoring

Run monitoring software on a computer connected wirelessly to the network

trap

SNMP agents can be programmed to detect certain abnormal conditions (port goes down) that prompt the generation of SNMP ________ messages, where the agent sends the NMS unsolicited data once the specified condition (port goes down) on the managed device are met.

error rate

The calculated percentage of how often Bits are damaged in transit due to EMI or other interference

business continuity

The goal of a disaster recovery plan is to ensure ____________, which is the ability of the company to continue doing business with the least amount of interruption possible.

packet drops

The quantity of packets that are dropped due to .... being damaged beyond use, arrive after their expiration, or are not allowed through an interface

CoS

The term QoS refers to techniques that are performed at various OSI layers via several protocols. By contrast, the term ______________ refers only to techniques performed at Layer 2, on Ethernet frames, and is one method of implementing QoS.

baseline

To identify when there's a problem on the network, you must first know what is normal for that network. A(n) ____________ is a report of the network's normal state of operation and might include a range of acceptable measurements.

QoS

To support voice and video traffic on a network, network administrators must pay attention to a network's _________, which is a group of techniques for adjusting the priority a network assigns to various types of transmissions

iSCSI

Transport layer protocol that runs on top of TCP to allow fast transmissions over LANs, WANs, and the Internet. It can work on a twisted-pair Ethernet network with ordinary Ethernet NICs. ______ is an evolution of SCSI (Small Computer System Interface), which is a fast transmission standard used by internal hard drives and operating systems in file servers.

syslog

UNIX or Linux based computer log containing monitored device information

RAID 10

Using four or more disks, data is mirrored within each pair of disks, and then striped to multiple pairs of disks.

jitter

When successive packets experience varying amounts of latency, resulting in their arriving out of order

event log

Windows-based computer log containing monitored device information

UPS

_____ is a battery-operated power source directly attached to one or more devices and to a power supply, such as a wall outlet, that prevents undesired fluctuations of the wall outlet's AC power from harming the device or interrupting its services.

AC

_____ power comes from the power station through the wall outlet to a device for it's use.

NAS

________ is a specialized storage device or group of storage devices that provides centralized, fault-tolerant data storage for a network. You can think of _______ as a unique type of server dedicated to data sharing.

SAN

_________ is a distinct network of storage devices that communicate directly with each other and with other networks.

CARP

____________ allows a pool of computers or interfaces to share one or more IP addresses. This pool is known as a group of redundancy or redundancy group. When using _______, one device, acting as the group master, receives requests for an IP address, then parcels out the requests to one of several devices in the group.

DiffServ

____________ is a simple technique that addresses QoS issues by prioritizing traffic at Layer 3. _______ takes into account all types of network traffic, not just the time-sensitive services such as voice and video. That way, it can assign voice streams a high priority and at the same time assign unessential data streams (for example, an employee surfing the Internet on his lunch hour) a low priority.

Network Management

_____________ refers to the assessment, monitoring and maintenance of all aspects of a network.

Spiceworks

______________ is a type of network monitoring software because it can be configured to monitor multiple devices on a network at one time.

Wireshark

______________ is a type of protocol analyzer because it monitors traffic on the interface between a single device and the network.

Clustering

______________ refers to the technique of grouping multiple devices so they appear as a single device to the rest of the network. ____________ can be configured with groups of servers, routers, or applications.

Incident response policy

______________ specifically define the characteristics of an event that qualifies as a formal incident and the steps that should be followed as a result. Qualifying incidents take into account the full spectrum of possible events, which might include a break-in, fire, weather-related emergency, hacking attack, discovery of illegal content or activity on an employee's computer, malware outbreak, or a full-scale, environmental disaster that shuts down businesses throughout the city or state. The policy is written with the intent of keeping people safe; protecting sensitive data; ensuring network availability and integrity; and collecting data to determine what went wrong, who is responsible, and what actions should be taken in the future to prevent similar damage.

fault tolerance

___________________ is the capacity for a system to continue performing despite an unexpected hardware or software malfunction.

disaster recovery

____________________ is the process of restoring your critical functionality and data after an outage that affects more than a single system or a limited group of users.

automatic failover

a component that is able to automatically assume the responsibilities of an identical component that fails - example: a backup router automatically assumes the role of a failed router

load balancing

automatic distribution of traffic over multiple connections to optimize performance and fault tolerance

MTTR

average amount of time required to repair the failed device

MTBF

average amount of time that will pass before the next failure is expected to occur

polling

collecting data from multiple network devices on regular intervals

fault management

detection and signaling of device, link, or component failures

failure

deviation from a specified level of system performance for a given period of time

ghosts

frames that are not actually frames - caused by device misinterpreting stray voltage on wire

MIB

list of objects managed by the NMS, as well as the descriptions of these objects - contains data about an object's performance in a database format that can be mined and analyzed

fault

malfunction of one component of a system

utilization

metric refers to the actual throughput used as a percentage of available bandwidth

performance management

monitoring how well links and devices are keeping up with the demands placed on them

giants

packets larger than maximum packet size (more than 1518 bytes)

packet loss

packets lost due to unknown protocol, unrecognized port, network noise - never arrive at destination

runts

packets smaller than minimum packet size (less than 64 bytes)

discarded packets

packets that arrive at destination but are discarded due to buffer overflow, latency, bottlenecks or congestion

interface resets

repeated resets of the connection (interface misconfiguration)

network management agent

software routine that collects information about the device's operation and provides it to the NMS

Fibre Channel

storage networking architecture that runs separately from Ethernet networks to maximize speed of data storage and access. Fiber-optic cable is much more commonly used. Requires special hardware, which makes it an expensive storage connection technology.

NMS

the central collection point .... the management console - the software installed on the management console that collects and displays the data gathered from the managed devices

link aggregation -or- port aggregation

the combination of multiple network interfaces or ports to act as one logical interface