Acronyms Flashcards
1
Q
3G
A
3rd-generation wireless data standard for cell phones and other mobile devices; max speed 168 Mbps
2
Q
4G
A
popularly implemented as LTE (long term evolution) with theoretical download speeds of 300 Mbps
3
Q
4to6
A
Internet connectivity technology that turn IPv4 into IPv6 to get to an IPv6 capable router
4
Q
6in4
A
IPv6 tunneling stanard that can go through IPv4 Network Address Translation (NAT)
5
Q
6to4
A
IPv6 tunneling protocol that doesn’t require a tunnel broker. Directly connect 2 routers that normally require public IPv4 address.
6
Q
8P8C
A
8 position 8 contact; 4-pair connector used on the end of network cable— RJ45 connector
7
Q
10 GbE
A
10 Gigabit Ethernet; very fast Ethernet designation, with a # of fiber-optic and copper standards
8
Q
10Base2
A
last true bus-standard network where nodes connected to a common share length of coaxial cable
9
Q
10BaseFL
A
Fiber-optic implementation of Ethernet that runs at 10Mbps using base-band signaling; max length is 2km
10
Q
10BaseT
A
Ethernet LAN designed to run on UTP cabling; runs 10Mbps with base-band signaling; max length between NIC and hub is 100m
11
Q
10GBaseER/10GBaseEW
A
10GbE stanard using 1500nm single-mode fiber; max length 40km
12
Q
10GBaseLR/10GBaseLW
A
10 GbE standard using 1310-nm single-mode fiber; max length 10km
13
Q
10GBaseSR/10GBaseSW
A
10 GbE standard using 850-nm multimode fiber; max lenth 300m.
14
Q
10GBaseT
A
10 GbE stanard designed to un on Cat 6a UTP cabling; max length 100m
15
Q
66 block
A
Patch panel used in telephone networks displaced by 110 blocks in networking
16
Q
100BaseFX
A
Ethernet LAN designed to run on fiber-optic cabling; runs at 100Mbps with baseband signaling; max length 400m for half-duplex and 2km for full-duplex
17
Q
100BaseT
A
Ethernet LAN designed to run on UTP cabling; runs at 100Mbps with baseband signaling; uses 2 pairs of wires on Cat 5 or better
18
Q
100BaseT4
A
Ethernet LAN designed to run on UTP cabling; runs at 100 Mbps and uses 4-pair Cat 3 or better cabling; made obsolete by 100BaseT
19
Q
100BaseTX
A
technically accurate but little used name for 100BaseT
20
Q
110 block
A
aka 110-punchdown block; connection gridwork used to link UTP and STP cables behind RJ-45 patch panel
21
Q
802 committee
A
IEEE committee responsible for all Ethernet standards
22
Q
802.1X
A
port-authentication network access control mechanism for networks
23
Q
802.3
A
Ethernet
24
Q
802.3ab
A
IEEE standard for 1000BaseT
25
802.3z
umbrella IEEE standard for all versions of Gigabit Ethernet other than 1000BaseT
26
802.11a
wireless standard that operates in the frequency range of 5GHz and throughput of up to 54 Mbps
27
802.11ac
wireless standard that operates on frequency range of 5 GHz and throughput of up to 1 Gbps
28
802.11a-ht
technical terms for mixed mode 802.11a and 802.11g operation; both tech are simultaneously supported
29
802.11b
1st popular wireless standard operating at frequency range of 2.4 GHz and throughput of up to 11 Mbps
30
802.11g
older wireless standard that operates on 2.4 GHz band with max throughput of 54 Mbps; superseded by 802.11n
31
802.11g-ht
goes along with 802.11a-ht standard; mixed mode operation
32
802.11i
wireless standard that added security features
33
802.11n
increases transfer speeds and adds support for MIMO by using multiple antennas; can operate on 2.4 or 5 GHz frequency band with max throughput of 400 Mbps; superseded by 802.11ac
34
1000BaseCX
Gigabit Ethernet standard using copper cabling with max 25m distance
35
1000BaseLX
Gigabit Ethernet standard using single-mode fiber cabling with max 5km distance
36
1000BaseSX
Gigabit Ethernet standard using multimode fiber cabling and max 500m distance
37
1000BaseT
Gigabit Ethernet standard using Cat5e/6 UTP cabling with 100m max distance
38
1000BaseTX
short-lived gigabit-over-UTP standard form; simpler to implement than 1000BaseT but required Cat 6 cable
39
1000BaseX
umbrella Gigabit Ethernet standard; aka 802.3z
40
A records
DNS records that map host names to their IPv4 addresses
41
AAA
Authentication, Authorization, Accounting; security philosophy where computer trying to connect to a network must first present credentials in order to be authenticated
42
AAAA Records
DNS records that map host names to their IPv6 addresses
43
absorption
quality of building materials to reduce or eliminate Wi-fi signal
44
acceptable use policy
document that defines what a person may and may not do on an organization's computers and network
45
access control
defines degree of permission granted to use a resource; from a switch pot to a particular file to a physical door in the building
46
ACL
access control list; defined list of permissions that a user can perform on a shared resource
47
ACS
Access Control Server; cisco program/process/server that makes decision to admit or deny a node based on posture assessment; directs access device to allow connection or redirection or denial
48
access port
regular port in switch that has been configured as part of VLAN; port that hosts connect to; opposite of a trunk port
49
Active Directory
form of directory services
50
activity light
LED on NIC, hub, or switch that blinks rapidly to show data transfers over network
51
ad hoc mode
each node is in direct contact with every other node in a decentralized free-for-all; similar to mesh topology
52
ANT+
Adaptive Network Technology; low-speed, high-power networking tech; used in place of Bluetooth (for smart phones and exercise machines)
53
ARP
Address Resolution Protocol; in TCP/IP suite used with command-line utility of same name to determine MAC address that goes with IP address
54
administrative accounts
specialized user accounts that have granted sufficient access rights and authority; some exist as default of system and have all authority throughout system
55
ADSL
asymmetric digital subscriber line; fully digital dedicated connection to telephone system that provides download speeds of 9 Mbps and upload of 1 Mbps
56
AES
Advanced Encryption Standard; block cipher created in late 1990s that uses a 128-bit block size and 128-, 192-. or 256-bit key size; practically uncrackable
57
adware
program that monitors types of web sites you frequent and targets ads to you
58
agent
software that runs within a client and reports client's security characteristics to ACS to be approved or denied
59
agent-less
client that has its posture checked and presented by non-permanent software that executes as part of connection process; does not run directly within the client but on behalf of the client
60
aggregation
router hierarchy; every router under high router uses subnet of router's existing routes
61
air gap
act of physically separating a network from every other network
62
Aircrack-ng
open source tool for penetration testing aspects of wireless networks
63
alert
proactive message sent from an SNMP manager as a result of a trap issued by agent; alert may be e-mail, SMS message, voicemail, or other
64
algorithm
set of rules for solving a problem given a # of steps
65
allow
permission for data or communication to pass through or access a resource; specific allowances are exceptions
66
ARIN
American Registry for Internet Numbers; parcels out IP addresses to large ISPs and major corporations in North America
67
amplification
aspect of DoS attack that makes a server do a lot of processing and responding
68
amplified DoS attack
sends a small amount of traffic to a service which produces a larger response that is sent to a spoofed IP address, overwhelming the victim machine
69
APC
Angled Physical Contact; Fiber-optic connector that make physical contact between 2 f-o cables; 8-degree angle to curved end, lowering signal loss
70
anti-malware program
software that attempts to block several types of threats to a client' i.e. viruses, worms, and other unapproved software installations and executions
71
antivirus
software that attempts to prevent viruses from installing or executing on a client; some can try to remove or eradicate effects of a virus
72
anycast
method of addressing groups of computers as though they were one computer; gives computers the same IP address
73
Apache HTTP Server
open source HTTP server program that runs on a variety of operating systems
74
application log
tracks application events; i.e. opening and closing; different types record different events
75
API
Application Programming Interface; shared functions, subroutines, and libraries that allow programs on a machine to communicate with OS and other programs
76
application/context aware
Advanced feature of some firewalls where content of data is inspected to make sure it's from appropriate application; bad packets are denied
77
approval process
1 or more decision makers consider a impact of change and funding; if the change, funding, and impact are acceptable the change is approved
78
archive
creation/storage of retrievable copies of electronic data for legal and functional purposes
79
archive bit
attribute of a file that shows whether the file has been backed up since the last change
80
Area ID
address assigned to routers in an OSPF (open shortest path first) network to prevent flooding beyond routers network
81
areas
groups of OSPF routers designed to maximize routing efficiency while keep broadcast traffic managed; assigned a 32-bit value
82
ARP cache poisoning
attacker associates his MAC address with someone else's IP address so all traffic is sent to him first; sends out unsolicited ARPs which can be requests or replies
83
arping
command used to discover hosts on a network (like a ping) but replies on ARP rather than ICMP; only works in broadcast domain
84
asset disposal
reusing, repurposing, or recycling computing devices that follows system life cycle policies in organizations
85
asset management
managing each aspect of a network from documentation to performance to hardware
86
ADSL
asymmetric digital subscriber line; fully digital, dedicated connection to telephone system that provides download speeds of 9 Mbps and upload speeds of 1 Mbps
87
asymmetric-key algorithm
encryption method in which key used to encrypt a message and decrypt are different
88
ATM
Asynchronous Transfer Mode; network tech that runs at speeds between 25 and 622 Mbps using fiber-optic cabling or Cat 5 or better UTP
89
attenuation
degradation of signal over distance for networking cable
90
authentication
process that proves good data traffic truly came from where it says it originated by verifying send/receive users and computers
91
AS
Authentication Server; In Kerberos, a system that hands out Ticket-Granting Tickers to clients after comparing client hash to its own
92
authoritative DNS servers
DNS servers that hold IP addresses and names of systems for a particular domain called forward lookup zones; they also have reverse lookup zones
93
authoritative name servers
another name for authoritative DNS servers
94
authorization
step in AAA philosophy during which client's permissions are decided upon
95
APIPA
networking feature in operating systems that enables DHCP clients to self-configure an IP address and subnet mask automatically when a DHCP server isn't available
96
AS
Autonomous System; one or more networks that are governed by single protocol which provides routing for Internet backbone
97
back up
save important data in a secondary location as a safety precaution against loss of data
98
backup
archive of important data that disaster recovery team can retrieve in case of disaster
99
BDR
backup designated router; 2nd router set to take over is designated router fails
100
backup generator
onsite generator that provides electricity if the power fails
101
badge
card-shaped device used for authentication; something you have; a possession factor
102
bandwidth
piece of the spectrum occupied by some form of signal; higher the bandwidth, the faster the signal; when one user is occupying it, others must wait
103
bandwidth saturation
frequency of a band is filled to capacity
104
bandwidth speed tester
web sites for measuring an Internet connection throughput, download and upload
105
banner grabbing
malicious user gains access to open port and uses it to probe a host to gain info and access
106
baseband
digital signaling that has only 1 signal on the cable at a time; 1, 0, or idle
107
baseline
static image of a system's performance when all elements are known to be working
108
basic NAT
translates a computer's private or internal IP address to a global IP address
109
BRI
Basic Rate Interface; consists of 2 B channels which can carry voice or data at 64 Kbps and a D channel which carries setup, config, and data at 16 Kbps
110
BSSID
Basic Service Set Identifier; naming scheme in wireless networks
111
baud
one analog cycle on a telephone line
112
baud rate
number of bauds per second; early days of telephone data the baud rate was often analogous to bits per second; not true anymore
113
B channel
Bearer channel; type of ISDN channel that carries data and voice info using standard DS0 channels at 64 Kbps
114
BiDi transceiver
bidirectional transceiver; full-duplex fiber-optic connector that relies on wave division multiplexing to differentiate wave signals on a single fiber, creating single-strand fiber transmission
115
biometric
human physical characteristic that can be measured and saved as authentication in granting the user access to a network; i.e. fingerprints, facial scans, retinal scans, voice pattern recognition, and other
116
biometric devices
scan fingerprints, retinas, sound of voice to provide foolproof replacement for passwords
117
BERT
Bit Error Rate Test; end-to-end test that verifies a T-carrier connection
118
block
access that is denied to or from a resource; can be on a firewall, ACS, or other secure gateway
119
block cipher
encryption algorithm in which data is encrypted in chunks of a certain length; popular in wired networks
120
blocks
contiguous ranges of IP addresses that are assigned to organizations and end users by IANA
121
Bluejacking
process of sending unsolicited messages to another Bluetooth device
122
Bluesnarfing
use of weaknesses in Bluthtooth standard to steal info from other Bluetooth devices
123
BNC connector
used for 10Base2 coaxial cable; have to be locked into place by turning locking ring 90 degrees
124
BNC coupler
passive connector used to join 2 segments of coaxial cables that are terminated with BNC connectors
125
bonding
2 or more NICs in a system working together to act as a single NIC
126
BOOTP
Bootstrap Protocol; allows computers to discover and receive an IP address from a DHCP server prior to booting the OS
127
BGP-4
Border Gateway Protocol; exterior gateway routing protocol that enables groups of routers to share ino so that efficient, loop-free routes can be established
128
botnet
group of computers under control of 1 operator for malicious purposes
129
bottleneck
spot on a network where traffic slows precipitously
130
bounce
signal sent by one device taking many different paths to get to receiving systems
131
bps
bits per second; measurement of how fast data is moved across a transmission medium; Gigabit Ethernet moves 1,000,000,000 bps
132
bridge
device that connects 2 networks and passes traffic between them based on node address so that traffic between nodes on 1 network doesn't appear on the other
133
bridge loop
negative situation in which bridging devices (i.e. switches) are installed in a loop configuration, continuously; switches using STP (Spanning Tree Protocol) prevent them by turning off loop ports
134
bridged connection
early type of DSL connection that made line function as if you snapped an Ethernet cable into your NIC
135
bridging loop
physical wiring of a cicuitous path between 2 or more switches causing them to loop
136
BYOD
Bring Your Own Device; users bring own network-enabled device to work; must use on-boarding and off-boarding technologies
137
broadband
analog signaling that sends multiple signals over cable at the same time; i.e. cable television; 0, 1, and idle states exist on multiple channels on same cable
138
broadcast
frame or packet addressed to all machines on a broadcast domain
139
broadcast address
address a NIC attaches to a frame when it wants every other NIC on the network to read it
140
broadcast domain
network of computers that will hear each other's broadcasts; aka collision domain
141
broadcast storm
result of one or more devices sending a nonstop flurry of broadcast frames on the network
142
browser
software program specifically designed to retrieve, interpret, and display web pages
143
brute force
type of attack where every permutation of data is tried in an attempt to discover protected info; most commonly used on password cracking
144
buffer
component of fiber-optic cable that adds strength to the cable
145
building entrance
location where all cables from outside world enter the building
146
bus topology
network topology that uses a single bus cable that connects all of the computers in a line; must be terminated to prevent signal reflection
147
BCP
business continuity planning; process of defining steps to be taken in event of physical corporate crisis to continue operations; includes creation of documents to specify facilities, equipment, resources, personnel, and their roles
148
butt set
device that can tap into a 66 or 110 punchdown block to see if a line is working
149
byte
8 continuous bits; fundamental data unit of personal computers; storing equivalent of 1 character; basic unit of measurement for computer storage; counted in powers of 2
150
CAB files
cabinet files; compressed and used during Microsoft operating system installation to store smaller files such as device drivers
151
cable certifier
powerful cable testing device used by professional installers to test electrical characteristics of cable then generate certification report if it passes TIA/EIA standards
152
cable drop
location where cable comes out of wall to workstation
153
cable modem
bridge device that interconnects cable company's DOCSIS service to user's Ethernet network; cable modem is demarc in most locations
154
cable stripper
device that enables creation of UTP cables
155
cable tester
generic name for device that tests cables; continuity, electrical shorts, crossed wires, other electrical characteristics
156
cable tray
device for organizing cable runs in drop ceiling
157
cache
special area of RAM that stores frequently accessed data; number of applications that take advantage of the cache
158
cached lookup
list kept by DNS server of IP addresses it already resolved so it won't have to re-resolve a FQDN that is already checked
159
cache-only DNS servers
do not have any forward lookup zones; resolve names of systems on Internet for network, but not responsible for telling other DNS servers names of clients
160
caching engine
server dedicated to storing cache info on your network; reduce overall network traffic dramatically
161
Cacti
popular network graphing program
162
CAN
campus area network; network installed in a medium-sized space spanning multiple buildings
163
CNAME
canonical name; less common type of DNS record that acts a computer's alias
164
captive portal
Wi-fi network implementation used in facilities that directs attempts to connect to network to an internal Web page for that facility; used to force terms of service on users
165
capture file
file in which collected packets from a packet sniffer program are stored
166
card
generic term for anything that you can snap into an expansion slot
167
CSMA/CA
carrier sense multiple access with collision avoidance; access method used on wireless networks; before hosts send out info they first listen for traffic, if it's free they send out a signal
168
CSMA/CD
carrier sense multiple access with collision detection; older Ethernet systems used in wired LAN technologies enabling frames of data to flow through network and reach address locations; if collision occurred they would have to resend
169
Cat 3
Category 3 wire; TIA/EIA standard for UTP wiring that can operate up to 16 Mbps
170
Cat 5
Category 5 wire; TIA/EIA standard for UTP wiring that can operate up to 100 Mbps
171
Cat 5e
Category 5e wire; TIA/EIA standard for UTP wiring with improved support for 100 Mbps using 2 pairs and 1000 Mbps using 4 pairs
172
Cat 6
Category 6 wire; TIA/EIA standard for UTP wiring with improved support for 1000 Mbps; supports 10 Gbps up to 55 meters
173
Cat 6a
Category 6a wire; TIA/EIA standard for UTP with support for 10 Gbps up to 100 meters
174
Cat 7
Category 7 wire; standard for UTP wiring with support for 10+ Gbps at 600 MHz max frequency
175
Cat rating
Category rating; grade assigned to cable to help network installers get right cable for right network technology; officially rated in MHz; indicating highest frequency bandwidth cable can handle
176
CCITT
Comite Consutatif Internationale Telephonique et Telegraphique; European standards body that established V standards for modems
177
central office
building that houses local exchanges and location where individual voice circuits come together
178
certificate
public encryption key signed with digital signature from a trusted 3rd party called certificate authority; key serves to validate identity of its holder when that person or company sends data to other parties
179
certifier
device that tests a cable to ensure that it can handle rated capacity
180
chain of custody
document used to track collection, handling, and transfer of evidence
181
CHAP
Challenge Handshake Authentication Protocol; remote access authentication protocol; serving system challenges remote client which must provide encrypted password
182
CRAM-MD5
Challenge-Response Authentication Mechanism-Message Digest 5; a tool for server authentication in SMTP servers
183
change management
process of initiating, approving, funding, implementing, and documenting significant changes to network
184
change management documentation
set of documents that defines procedures for changes to network
185
change management team
personnel who collect change requests, evaluate change, work with decision makers for approval, plan and implement approved changes, and document changes
186
change request
formal or informal document suggesting modification to some aspect of network or computing environment
187
channel
portion of wireless spectrum on which a particular wireless network operates; setting wireless networks to different channels enables separation of networks
188
channel bonding
wireless technology that enables wireless access points to use 2 channels for transmission
189
channel overlap
Drawback of 2.4 GHz wireless networks where channels shared some bandwidth with other channels; This is why only 3 2.4 GHz channels can be used in the US (1, 6, 11)
190
CSU/DSU
Channel Service Unit/Digital Service Unit; piece of equipment that connects a T-carrier leased line from telephone company to a customer's equipment; line encoding and conditioning functions and has loopback function for testing
191
chat
multiparty, real-time text conversation; internet's most popular version is known as Internet Relay Chat (IRC) which you converse in real-time.
192
checksum
simple error-detection method that adds a numerical value to each data packet; based on number of data bits in the packet; receiving node applies same formula to data and verifies numerical value is the same; if not data is corrupted and must be re-sent
193
CYOD
Choose your own device; deployment model where corporate employees select among catalog of approved mobile devices
194
cipher
series of complex and hard-to-reverse mathematics run on a string of ones and zeros in order to make a new set of seemingly meaningless ones and zeros
195
cipher lock
door unlocking system that uses a door handle, a latch, and a sequence of mechanical push buttons
196
ciphertext
output when cleartext is run through a cipher algorithm using a key
197
circuit switching
process for connecting 2 phones together on one circuit
198
Cisco IOS
Cisco's proprietary operating system
199
cladding
part of a fiber-optic cable that makes the light reflect down the fiber
200
class license
contiguous chunk of IP addresses passed out by IANA (Internet Assigned Numbers Authority)
201
CoS
Class of service; prioritization value used to apply to services, ports, or whatever a quality of service device might use
202
classful
Obsolete IPv4 addressing scheme that relied on original class blocks, such as Class A, Class B, and Class C
203
classless
IPv4 addressing scheme that does not rely on original class blocks
204
CIDR
CLassless Inter-Domain Routing; The basis of allocating and routing classless addresses, not restricting subnet masks to /8, /16, or /24
205
classless subnet
A subnet that does not fall into the common classes
206
cleartext credentials
Any login process conducted over network where account names, passwords, or other authentication elements are sent from client or server in unencrypted fashion
207
client
computer program that uses services of another computer program; software that extracts info form server
208
client/server
relationship in which client software obtains services from a server on behalf of a user
209
client/server application
performs some or all of its processing on an application server rather than on client; client receives results of processing
210
client/server network
network that has dedicated server machines and client machines
211
client-to-site
A type of VPN connection where single computer logs into remote network and becomes a member of that network
212
CCTV
Closed-circuit television; self-contained, closed system in which video camera feeds signal to specific, dedicated monitors and storage devices
213
cloud computing
using internet to store files and run applications; i.e. Google Docs is a cloud computing application that enables you to run productivity applications over the Internet
214
cloud/server based
remote storage and access of software, especially anti-malware, where it can be singularly updated; central storage allows users to access and run current versions of software easily; client must initiate access to and launching of software
215
cloud/server-based anti-malware
remote storage and access of software designed to protect against malicious software where it can be updated
216
clustering
multiple pieces of equipment (servers) connected which appear to user and network as one logical device, providing data and services to organization for redundancy ad fault tolerance
217
CWDM
coarse wavelength division multiplexing; optical multiplexing technology in which a few signals of different optical wavelength could be combined to travel a short distance
218
coaxial cable
type of cable that contains central conductor wire surrounded by insulating material which is then surrounded by braided metal shield; center wire and braided metal shield share common axis or centerline
219
CDMA
code-division multiple access; early cellular telephone tech that used spread-spectrum transmission; obsolete
220
cold site
location that consists of building, facilities, desks, toilets, parking, and everything else needed minus computers
221
collision
result of 2 nodes transmitting at same time on multiple access network such as Ethernet; both frames may be lost or partial frames may result
222
collision light
light on some older NICs that flickers when a network collision is detected
223
command
request, typed from a terminal or embedded in a file, to perform an operation or execute particular program
224
CIFS
Common Internet File System; protocol that NetBIOS used to share folders and printers; still common even on UNIX/Linux systems
225
community cloud
private cloud paid for and used by more than one organization
226
compatibility issue
when different pieces of hardware or software don't work together correctly
227
compatibility requirements
with respect to network install and upgrades, requirements that deal with how well new tech integrates with older or existing tech
228
complete algorithm
cipher and methods used to implement that cipher
229
computer forensics
science of gathering, preserving, and presenting evidence stored on a computer or form of digital media that is presentable in court
230
concentrator
device that brings together at a common center connections to a particular kind of network and implements that network internally
231
configuration management
set of documents, policies, and procedures designed to help you maintain and update your network in a logical, orderly fashion
232
configuration management documentation
define configuration of network; wiring diagrams, network diagrams, baselines, and policy/procedure/configuration documentation
233
configurations
settings stored in devices that define how they are to operate
234
connection
term used to refer to communication between 2 computers
235
connectionless
type of communication characterized by sending packets that are acknowledged by destination host; UDP is quintessential connectionless protocol in TCP/IP suite
236
connectionless communication
protocol that does not establish and verify a connection between hosts before sending data; sends data and hopes for the best; faster than connection-oriented protocols; UDP is an example
237
connection-oriented
network communications between 2 hosts that includes negotiation between hosts to establish comm session; data segments are then transferred between hosts, with each being acknowledged before another can be sent; closure of comm is conducted at end of data transfer; TCP only one
238
connection-oriented communication
protocol that establishes a connection between 2 hosts before transmitting data and verifies receipt before closing connection between hosts
239
console port
connection jack in a switch used exclusively to connect a computer that will manage switch
240
content filter
advanced networking device that implements content filtering, enabling admin to filter traffic based on signatures or keywords
241
content switch
advanced networking device that works at least at layer 7 and hides servers behind a single IP
242
contingency plan
documents that set out how to limit damage and recover from an incident
243
contingency planning
process of creating documents that set out how to limit damage and recover quickly from an incident
244
continuity
physical connection of wires in a network
245
continuity tester
inexpensive network tester that can only test for continuity on a line
246
convergence
point at which routing tables for all routers in a network are updated
247
copy backup
type of backup similar to normal or full, in that all selected files on a system are backed up; type of backup does NOT change archive bit of files being backed up
248
core
central glass of fiber-optic cable that carries the light signal
249
COBO
corporate-owned business only; deployment model where corporation owns all mobile devices issued to employees; whitelist of approved applications they can install
250
cost
arbitrary metric value assigned to a network route with OSFP-capable routers
251
counter
predefined event that is recorded to a log file
252
CRC
cyclic redundancy check; mathematical method used to check for errors in long streams of transmitted data with high accuracy
253
crimper
aka crimping tool; tool used to secure a crimp or an RJ-45 connector onto end of table
254
crossover cable
specially terminated UTP cable used to interconnect routers or switches or connect network cards without a switch; reverse sending and receiving wire pairs from one end to the other
255
cross-platform support
standards created to enable terminals from different companies to interact with each other
256
crosstalk
electrical signal interference between 2 cables that are in close proximity to each other
257
crypto-malware
malicious software that uses some form of encryption to lock a user out of system
258
CSMA/CA
carrier sense multiple access with collision avoidance; before host sends data they listen for traffic, if error is detected they wait and then try again; wireless
259
CSMA/CD
carrier sense multiple access with collision detection; obsolete
260
CSU/DSU
Channel Service Unit/Data Service Unit; connects a T-carrier leased line from telephone company to customer's equipment; performs line encoding and conditioning functions
261
CPE
customer-premises equipment; primary distribution box and customer owned/managed equipment that exists on customer side of demarc
262
daily backup
aka daily copy backup; makes a copy of all files that have been changed that day without changing the archive bits of those files
263
daisy-chain
method of connecting together several devices along a bus and managing the signals for each device
264
data backup
process of creating extra copies of data to be used in case primary data source fails
265
DES
Data Encryption Standard; symmetric-key algorithm developed by U.S. government in 1970s; used a 64-bit block and 56-bit key; 56-bit key made DES susceptible to brute-force attacks
266
DOCSIS
Data Over Cable Service Interface Specification; unique protocol used by cable modem networks
267
datagram
connectionless transfer unit created with User Datagram Protocol designed for quick transfer over a packet-switched network
268
DTLS VPN
datagram TLS Virtual Private Network; optimizes connections for delay-sensitive applications (i.e. voice and video)
269
DB-9
a 9-pin, D-shaped subminiature connector used in serial port connections
270
DB-25
25-pin, D-shaped subminiature connector used in parallel and older serial port connections
271
dead spot
place that should be covered by network signal but devices do not get signal
272
deauth attack
deauthentication attack; form of DoS attack that targets 802.11 Wi-Fi networks by sending out a fram that kicks a wireless client off its current WAP connection; rogue WAP nearby presents stronger signal and then intercepts communications to and from
273
dB
decibel; measurement of quality of signal
274
dedicated circuit
circuit that runs from a breaker box to specific outlets
275
dedicated line
telephone line that is always open, or connected, circuit; usually do not have telephone numbers
276
dedicated server
machine that does not use any client functions, only server functions
277
de-encapsulation
process of stripping all extra header info from packet as data moves up a protocol stack
278
default
software function or operation that occurs automatically unless user specifies something else
279
default gateway
IP address of router that interconnects the LAN to wider network like the Internet; routers IP address is part of configuration for communicating with multiple networks using IP
280
D channel
Delta channel; type of ISDN line that transfers data to Kbps
281
demarc
device that marks dividing line of responsibility for functioning of a network between internal users and upstream service providers
282
demarc extension
any cabling that runs from network interface to whatever box is used by customer as demarc
283
DMZ
demilitarized zone; lightly protected or unprotected subnet network positioned between an outer firewall and organization's highly protected internal network; used mainly to host public address servers
284
demultiplexer
device that can extract and distribute individual streams of data that have been combined together to travel along a single shared network cable
285
DoS
denial of service; an effort to prevent users from gaining normal use of a resource
286
DoS attack
denial of service attack; attack that floods networked server with so many requests that it becomes overwhelmed and ceases functioning
287
DWDM
dense wavelength division multiplexing; optical multiplexing tech in which large number of optical signals of different optical wavelength could be combined to travel over relatively long fiber cables
288
DR
designated router; main router in an OSPF network that relays info to all other routers in area
289
destination port
fixed, predetermined number that defines function or session type in a TCP/IP network
290
device driver
subprogram to control communications between computer and peripheral hardware
291
device ID
last 6 digits of MAC address, identifying manufacturer's unique serial number for NIC
292
device types/requirements
with respect to installing and upgrading networks, these determine equipment needed to build network and how it should be organized
293
DORA
DHCP 4-way handshake; process in which client gets a lease for IPv4 address--- Discover, Offer, Request, and Ask
294
DHCP lease
created by DHCP server to allow system requesting DHCP IP info to use info for certain amount of time
295
DHCP relay
router process that passes DHCP requests and responses across router interfaces; comms can cross from one network to another within a router that has DHCP relay enabled and configured
296
DHCP scope
pool of IP addresses that DHCP server may allocate to clients requesting IP addresses or other IP info like DNS server addresses
297
DHCP snooping
switch process that monitors DHCP traffic, filtering out DHCP messages from untrusted sources; used to block attacks that use rogue DHCP server
298
dial-up lines
telephone lines with telephone numbers; must dial to make connection as opposed to dedicated line
299
differential backup
similar to incremental backup in that it backs up files that have been changed since last backup; does not change state of archive bit
300
DiffServ
differentiated services; underlying architecture that makes quality of service (QoS) work
301
DS1
digital signal 1; signaling method used by T1 lines which uses simple frame consisting of 25 pieces; a framing bit and 24 channels; holds single 8-bit DS0 data sample; make 193 bits per DS1 frame; frames transmitted 8000 times per second making total throughput of 1.544 Mbps
302
digital signature
encrypted hash of a private encryption key that verifies sender's identity to those who receive it
303
DSL
digital subscriber line; high-speed internet connection tech that uses regular phone line for connectivity
304
dipole antenna
standard straight-wire antenna that provides most omnidirectional function
305
DC
direct current; type of electric circuit where flow of electrons is in complete circl
306
directional antenna
focuses signal more toward specific direction
307
DSSS
direct-sequence spread-spectrum; spread-spectrum broadcasting method defined in the 802.11 standard that sends data out on different frequencies at the same time
308
disaster recovery
means and methods to recover primary infrastructure from a disaster; starts with a plan and includes data backups
309
DAC
discretionary access control; authorization method based on idea that there is owner of a resource who may at their discretion assign access to that resource; much more flexible than MAC (mandatory access control)
310
disk mirroring
process by which data is written to 2 or more disk drives; read and write speed is decreased but redundancy is increased; aka RAID level 1
311
disk striping
process by which data is spread among multiple drives; increases speed for both reads and writes, but provides no fault tolerance; aka RAID level 0
312
disk striping with parity
process by which data is spread among multiple drives, with parity info as well to provide fault tolerance; most common is RAID 5 where data and parity info is spread across 3 or more drives
313
dispersion
diffusion over distance of light propagating down fiber cable
314
distance vector
set of routing protocols that calculates total cost to get to a particular network ID and compares cost to total cost of all other routes
315
DCS
distributed control system; small controller added directly to machine used to distribute computing load
316
DCF
Distributed Coordination Function; 1 of 2 methods of collision avoidance defined by 802.11 standard and only 1 currently implemented; specifies strict rules for sending data on network media
317
DDoS
distributed denial of service; multicomputer assault on network resource that attempts to prevent regular users from receiving services from resources; can be used to crash systems
318
distributed switching
centralized installation, configuration, and handling of every switch in a virtualized network
319
DLL
dynamic link library; file of executable functions or data that can be used by Windows application; DLL provides 1 or more particular functions and program accesses the functions by creating links to DLL
320
DNS cache poisoning
attack that adds or changes info in DNS server to point host names to incorrect IP addresses under attackers control; when client visits attackers site, malware is installed
321
DNS domain
specific branch of DNS name space; top-level DNS domains include .com, .gov, .edu
322
DNS forwarding
DNS server configuration that sends DNS requests to another DNS server
323
DNS resolver cache
used by Windows DNS clients to keep track of DNS info
324
DNS root servers
highest in hierarchy of DNS servers running Internet
325
DNS server
system that runs a special DNS server program
326
DNS tree
hierarchy of DNS domains and individual computer names organized into tree-like structure, top of which is root
327
document
mendium and data recorded on it for human use; report sheet or book; any record that has permanence and can be read by human or machine
328
documentation
collection of organized documents or info recorded in documents; instructional material specifying inputs, operations, and outputs of computer program or system
329
domain
describes a grouping of users, computers, and/or networks; group of computers and users that shares a common account database and common security policy; group of computers that shares common element in DNS hierarchical name
330
domain controller
specifically configured to store user and server account info for its domain; store all account and security info in Active Directory domain service
331
dig
domain information groper; command-line tool in non-Windows systems used to diagnose DNS problems
332
DNS
Domain Name System; TCP/IP name resolution system that resolves host names to IP addresses, IP addresses to host names, and other bindings like DNS servers and mail servers for a domain
333
domain users and groups
defined across entire network domain
334
door access controls
methodology to grant permission or deny passage through doorway; computer-controlled, human-controlled, token-oriented, or other means
335
dotted decimal notation
shorthand method for discussing and configuring binary IP addresses
336
download
transfer of information from a remote computer system to user's system
337
drive mirroring
process of writing identical data to 2 hard drives on same controller at same time to provide data redundancy
338
DS0
digital signal rate created by converting analog sound into 8-bit chunks 8000 times a second with data stream of 64 Kbps; simplest data stream of digital part of phone system
339
DS1
signaling method used by T1 lines which uses relatively simple frame consisting of 25 pieces: a framing bit and 24 channels; holds single 8-bit DS0 data sample; combine to make 193 bits per DS1 frame; transmitted 8000 times/sex making total throughput of 1.544 Mbps
340
DSLAM
DSL Access Multiplexer; device located in telephone company's central office that connects multiple customers to Internet
341
DSL modem
device that enables customers to connect to Internet using DSP connection; isn't really a modem-- more like ISDN terminal adapter
342
DSP
digital signal processor; specialized microprocessor-like device that processes digital signals at expense of other capabilities; used in such specialized hardware as high-speed modems, multimedia sound cards, MIDI equipment, and real-time video capture and compression
343
dual stack
networking device, such as router or PC that runs both IPv4 and IPv6
344
duplexing
similar to mirroring in that in that data is written to and read from 2 physical drives for fault tolerance; separate controllers used for each drive for both fault tolerance and additional speed; considered RAID level 1
345
dynamic addressing
way for a computer to receive IP info automatically from a server program
346
DAI
Dynamic ARP Inspection; Cisco process that updates database of trusted systems; watches for false or suspicious ARPs and ignores them to prevent ARP cache poisoning and other malevolent efforts
347
DDNS
Dynamic DNS; protocol that enables DNS servers to get automatic updates of IP addresses of computers in forward lookup zones, mainly by talking to local DHCP server
348
DHCP
Dynamic Host Configuration Protocol; enables DHCP server to set TCP/IP settings automatically for a DHCP client
349
DMVPN
dynamic multipoint VPN; virtual private network solution optimized for connections between multiple locations directly
350
DNAT
dynamic NAT; type of Network Address Translation in which many computers can share a pool of routable IP addresses that number fewer than computers
351
dynamic port numbers
port numbers 49152-65535 recommended by IANA to be used as ephemeral port numbers
352
dynamic routing
process by which routers in internetwork automatically exchange info with other routers; requires dynamic routing protocol such as OSPF or RIP
353
dynamic routing protocol
supports building of automatic routing tables such as OSPF or RIP
354
E1
European counterpart of T1 connection that carries 32 channels at 64 Kbps for total of 2.048 Mbps-- slightly faster than T1
355
E3
European counterpart of T3 line that carries 16 E1 lines (512 channels) for total bandwidth of 34.368 Mbps-- slower than American T3
356
EAP-TLS
Extensible Authentication Protocol with Transport Layer Security; defines use of RADIUS server as well as mutual authentication, requiring certificates on server and client
357
EAP-TTLS
Extensible Authentication Protocol with Tunneled Transport Layer Security; similar to EAP-TLS but only uses single server-side certificate
358
edge device
hardware device that has been optimized to perform a task in coordination with other edge devices and controllers
359
edge router
connects 1 Autonomous System to another
360
effective permissions
permissions of all groups combined in any network operating system
361
EMI
electromagnetic interference; interference from 1 device to another resulting in poor performance in device's capabilities; similar to having static on your TV while running hair dryer or placing 2 monitors too close together and getting a "shaky" screen
362
electronic discovery
process of requesting and providing electronic and stored data and evidence in legal way
363
e-mail
electronic mail; messages (text) sent from 1 person to another via computer; can automatically send to large number of addresses (mailing list)
364
E-mail alert
notification sent by e-mail as result of an event; typical use is a notification sent from SNMP manager as a result of out-of-tolerance condition in SNMP managed device
365
e-mail client
program that runs on a computer and enables a user to send, receive, and organize e-mail
366
e-mail server
aka mail server; accepts incoming e-mail, sorts e-mail for recipients into mailboxes, and sends e-mail to other servers using SMTP
367
emulator
software or hardware that converts commands to and from host machine to entirely different platform; a program that enables you to run Nintendo games on your PC
368
encapsulation
process of putting packets from one protocol inside another; example is Ethernet which places TCP/IP packes inside Ethernet frames
369
encryption
method of securing messages by scrambling and encoding each packet as sent across unsecured medium like the Internet; each level provides multiple standards and options
370
endpoint
in TCP/IP world, session info stored in RAM
371
endpoints
correct term to use when discussing data each computer stores about connection between 2 computers' TCP/IP applications
372
end-to-end principle
early network concept that meant that applications and work should happen only at endpoints in a network, such as in a single client and single server
373
EDGE
Enhanced Data rates for GSM Evolution; early cellular telephone tech that used a SIM card; obsolete
374
EIGRP
Enhanced Interior Gateway Routing Protocol; Cisco's proprietary hybrid protocol that has elements of both distance vector and link state routing
375
SFP+
enhanced small form-factor pluggable; Fiber-optic connector used in 10 GbE networks
376
environment limitations
with respect to building and upgrading networks; refers to degree of access to facilities and physical access to infrastructure; type of building must be considered; access to walls and ceilings will factor into construction of network
377
environmental monitor
device used in telecomm rooms that keeps track of humidity, temperature, and more
378
ephemeral port
arbitrary number generated by sending computer that receiving computer uses as destination address when sending a return packet
379
equipment limitations
with respect to installing and upgrading networks, the degree of usage of any existing equipment, applications or cabling
380
equipment rack
metal structure used in equipment rooms to secure network hardware devices and patch panels; most are 19" wide; devices designed to fit in rack use a height measurement call units or U
381
ESD
electrostatic discharge; the movement of electrons from 1 boy to another; real menace to PCs because it can cause damage to semiconductors
382
Ethernet
name coined by Xerox for 1st standard of network cabling and protocols; based on bus topology; IEEE 802.3 subcommittee defines current specifications
383
EoP
Ethernet over Power; IEEE 1901 standard (aka HomePlug HD-PLC) provides high-speed home networking through building's existing power infrastructure
384
evil twin
attack that lures people into logging into a rouge access point that looks similar to a legit access point
385
HSPA+
Evolved High- Speed Packet Access; final wireless 3G data standard; transferring max speed up to 168 Mbps; though it rarely passed 10 Mbps
386
executable viruses
literally extensions of executables and unable to exist by themselves; once infected executable is run the virus loads into memory and adds copies of itself to other EXEs that are run
387
Exim
E-mail server for every major platform; fast and efficient
388
exit plan
documents and diagrams that identify best way out of a building in the even of an emergency and procedures to follow
389
ESS
Extended Service Set; single wireless access point servicing a given area that has been extended by adding more access points
390
ESSID
Extended Service Set Identifier; SSID applied to Extended Service Set as a networking name convention
391
EUI-48
Extended Unique Identifier, 48-bit; IEEE term for 48-bit MAC address assigned to network interface; 1st 24 bits are assigned by IEEE as organizationally unique identifier
392
EUI=64
Extended Unique Identifier, 64-bit; last 64 bits of IPv6 address, which are determined based on calculation based on device's 48-bit MAC address
393
EAP
Extensible Authentication Protocol; wrapper that EAP-compliant apps can use to accept one of many types of authentication; substantial use is in wireless network
394
external connections
network's connections to wider Internet; major concern when setting up a SOHO network
395
EDB
external data bus; primary data highway of all computers; everything in computer is tied directly or indirectly to EDB
396
external firewall
sits between perimeter network and Internet; responsible for bearing the brunt of attacks from Internet
397
external network address
added to MAC address of every computer on IPX/SPX network that defines every computer on the network; often referred to as network number
398
external threats
threats to network through external means; virus attacks and exploitation of users, security holes in OS or weakness of network hardware
399
fail close
defines condition of doors and locks in event of emergency; doors should close and lock
400
fail open
defines condition of doors and locks in the event of emergency; door should be open and unlocked
401
FAQ
frequently asked questions
402
FEXT
far-end crosstalk; crosstalk on opposite end of cable from signal's source
403
Fast Ethernet
nickname for 100-Mbps Ethernet standards; originally applied to 100BaseT
404
fault tolerance
capability of system to continue functioning after some part of system failure: RAID is an example
405
F-connector
screw-on connector used to terminate small-diameter coaxial cable such as RG-6 and RG-59 cables
406
FDDI
Fiber Distributed Data Interface; older tech fiber-optic network used in campus-sized installations; transfers data 100 Mbps and uses bus topology
407
FCC
Federal Communications Commission; In US, regulates public airwaves and rates PCs and other equipment according to amount of radiation emitted
408
fiber-optic cable
high-speed physical medium for transmitting data that uses light rather than electricity; made of high-purity glass fibers sealed within opaque tube; faster than copper wire
409
FC
Fibre Channel; self-contained high-speed storage environment with own storage arrays, cables, protocols, and switches; critical part of storage area networks
410
file hashing
when download provider hashes the contents of a file and publishes resulting message digest
411
file server
computer designated to store software, courseware, administrative tools, and other data on LAN or WAN; gives info to other computers via network when users enter personal access code
412
FTP
File Transfer Protocol; set of rules that allows 2 computers to talk to one another as a file transfer is carried out; used when you transfer a file from 1 computer to another across Internet
413
fire ratings
developed by Underwriters Laboratories (UL) and National Electrical Code (NEC) to define risk of network cables burning and creating noxious fumes
414
firewall
device that restricts traffic between LAN and Internet
415
FireWire
IEEE 1394 standard to send wide-band signals over thin connector system that plugs into TVs, VCRS, PCs, etc... serial bus developed by Apple and Texas Instruments enables connection of 60 devices at speeds of 100-800 Mbps
416
first responder
person or robot whose job is to react to notification of possible computer crime by determining severity, collecting info, document findings/actions, and provide info to proper authorities
417
flat name space
naming convention that gives each device only one name that be unique; used by NetBIOS; TCP/IP uses hierarchical name space
418
flat-surface connector
early fiber-optic connector that resulted in gap between fiber-optic junctions due to flat grind faces of fibers; was replaced by Angled Physical Contact (APC) connectors
419
flood guard
tech in modern switches that can detect and block excessive traffic
420
flow
stream of packets from 1 place to another
421
flow cache
stores sets of flows for interpretation and analysis
422
forensics report
document that describes details of gathering, securing, transporting, and investigating evidence
423
forward lookup zone
storage area in DNS server to store IP addresses and names of systems for particular domain(s)
424
forward proxy server
acts as middleman between clients and servers, making requests to network servers on behalf of clients; results sent to proxy server and then passed on to original client
425
fractional T1 access
service provided by many telephone companies where customers can purchase a number of individual channels in a T1 line in order to save money
426
frame
defined series of binary data that is basic container for discrete amount of data moving across a network; created in Layer 2 of OSI model
427
FCS
frame check sequence; sequence of bits palced in a frame that is used to check primary data for errors
428
Frame Relay
extremely efficient data transmission technique used to send digital info such as voice, data, LAN, WAN traffic quickly and cost-efficiently to many destinations from 1 port
429
FreeRADIUS
server software for UNIX/Linux Systems
430
freeware
software that is distributed for free with no license fee
431
FDM
frequency division multiplexing; process of keeping individual phone calls separate by adding different frequency multiplier to each phone call; separate phone calls by unique frequency range
432
frequency mismatch
problem older wireless networks with manual settings where the WAP transmitted on 1 channel and wireless client was set to access on a different channel
433
FHSS
frequency-hopping spread-spectrum; broadcasting method defined in 802.11 standard that sends data one 1 frequency at a time, constantly shifting frequencies
434
FAQ
frequently asked questions
435
FUBAR
Fouled Up Beyond All Recognition
436
full backup
archive created where every file selected is backed up, and archive bit is turned off for every file backed up
437
full-duplex
any device that can send and receive data simultaneously
438
fully meshed topology
mesh network where every node is directly connected to every other node
439
FQDN
fully qualified domain name; complete DNS name of a system from host name to top-level domain name; textual nomenclature to domain-organized resource; written left to right with host on left followed by hierarchical subdomains within top-level domain on right; each level is separated from any preceding or following layer by a dot
440
gain
strengthening and focusing of radio frequency output from a WAP
441
gateway router
router that acts as a default gateway in TCP/IP network
442
general logs
record updates to applications
443
geofencing
process of using mobile device's built-in GPS capabilities and mobile networking capabilities to set geographical constraints on where mobile device can be used
444
Get (SNMP)
query from SNMP manager sent to agent of managed device for status of management info base object
445
giga
prefix generally refers to quantity 1,073,741,824; 1 gigabyte is that many bytes; with frequencies giga refers to 1 billion; 1 gigahertz is 1,000,000,000 hertz
446
GBIC
gigabit interface converter; modular port that supports a standardized, wide variety of gigabit interface modules
447
gigabyte
1024 megabytes
448
global routing prefix
first 48 bits of an IPv6 unicast address, used to get a packet to its destination
449
GSM
Global System for Mobile; Early cellular telephone networking standard-- obsolete
450
global unicast address
second IPv6 address that every system needs in order to get on Internet
451
GFS
grandfather, father, son; tape rotation strategy used in data backups
452
graphing
type of software that creates visual representations and graphs of data collected by SNMP managers
453
greenfield mode
1 of 3 modes used with 802.11n wireless networks wherein everything is running at higher speed
454
ground loop
voltage differential that exists between 2 different grounding points
455
Group Policy
feature of Windows Active Directory that allows an administrator to apply policy settings to network users en masse
456
GPO
Group Policy Object; Enables network administrators to define multiple rights and permissions to entire sets of users at one time
457
groups
collections of network users who share similar tasks and need similar permissions
458
guest
operating system running as virtual machine inside a hypervisor
459
guest network
can contain or allow access to any resource that management deems acceptable
460
H.320
standard that uses multiple ISDN channels to transport video teleconferencing over a network
461
H.323
VoIP standard that handles initiation, setup, and delivery of VoIP sessions
462
hackers
people who break into computer systems; malicious=black hat; positive=white hat; middle-ground=gray hat
463
half-duplex
any device that can only send or receive data at any given moment
464
hardening
applying security hardware, software, and processes to your network to prevent bad things from happening
465
hardware appliance
physical network device, typically a "box" that implements and runs software or firmware to perform tasks; firewall, switch, router, print server, or other device
466
hardware tools
cable testers, TDRs, OTDRs, certifiers, voltage event recorders, protocol analyzers, cable strippers, multimeters, tone probes/generators, butt sets, punchdown tools used to configure/troubleshoot network
467
hash
mathematical function used in cryptography that is run on a string of binary digits of any length that results in value of some fixed length
468
HEC
HDMI Ethernet Channel; Ethernet-enabled HDMI ports that combine video, audio, and data on single cable
469
header
first section of a frame, packet, segment or datagram
470
HVAC
heating, ventilation, and air conditioning; all of equipment involved in heating and cooling environments within a facility
471
hex
hexadecimal; hex symbols based on numbering system of 16 (computer short-hand for binary); use 10 digits and 6 letters to condense 0 and 1 to binary
472
hierarchical name space
naming scheme where full name of each object includes its position within hierarchy
473
HA
high availability; collection of technologies and procedures that work together to keep an application available at all times
474
high-speed WAN Internet cards
type of router expansion card that enables connection to 2 different ISPs
475
history logs
logs that track history of how a user access network resources
476
home automation
process of remotely controlling household devices, such as lights, thermostats, cameras, and washer/dryer
477
home page
either web page that browser is set to use when starts up or main web page for business, organization, or person
478
honeynet
network created by honeypot in order to lure in hackers
479
honeypot
area of a network that an admin sets up for express purpose of attracting a computer hacker
480
hop
passage of packet through router
481
hop count
older metric used in RIP routers; # of routers a packet must cross to get from router to network
482
horizontal cabling
cabling that connects equipment room to work areas
483
host
single device on TCP/IP network that has IP address
484
host ID
portion of IP address that defines a specific machine in a subnet
485
host name
individual computer name in DNS naming convention
486
host-based anti-malware
anti-malware software that is installed on individual systems as opposed to network at large
487
host-based firewall
software firewall installed on "host" that provides firewall services for just that machine
488
hostname
command-line tool that returns the host name of computer it is run on
489
host file
predecessor to DNS, static text file that resides on computer and used to resolve DNS host names to IP addresses
490
host-to-host
type of VPN connection in which single host establishes link with remote, single host
491
host-to-site
type of VPN connection where host logs into remote network as if it were any other local resource of that network
492
hot site
complete backup facility to continue business operations; has all resources in place, computers, network infrastructure and current backups
493
hotspot
wireless access point that is connected to cellular data network (4G); can be permanent or portable
494
HTML
Hypertext Markup Language; ASCII-based script-like language for creating hypertext doc like those on WWW
495
HTTPS
HTTP over SSL; secure form of HTTP in which hypertext is encrypted by TLS (Transport Layer Security) before being sent onto network
496
hub
electronic device that sits at center of star topology network, providing common point for connection of network devices
497
HMI
human machine interface; DCS (distributed control system) computer or set of controls that exists between controller and human operator
498
hybrid cloud
public and private cloud resources, connected to achieve some target result
499
hybrid topology
mix or blend of 2 different topologies
500
hypertext
document that has been marked up to enable user to select words or pictures within document, click them, and connect to further info
501
HTML
Hypertext Markup Language
