Short Definitions Flashcards
Become Familiar with common terms
Private Cloud
A cloud infrastructure operated solely for a single organisation that can be managed internally or by a third party and host internally or externally
Public Cloud
When the cloud is rendered over a network that is open for public use
Community Cloud
Shares infrastructure between several organisations from a specific community that can be managed internally or by a third party and hosted internally or externally
Hybrid Cloud
Two or more clouds (private, public or community) that retain unique names but are bound together, offering the benefits of multiple deployment models
SNMP
Simple Network Management Protocol is a protocol that governs network management. The protocol reports on whether a device is functioning properly
DoS - reflective/amplified
Uses potentially legitimate thridparty component to send the attack traffic to a victim, hiding the attackers identity. The attackers send packets to the reflector servers with a source IP address set to their victim’s IP, indirectly overwhelming the victim with the response packets. DNS and NTP servers are particularly susceptible to this attack
DoS - Smurfing
a DDoS attack in which large numbers of Internet Control Message Protocol (ICMP) packets with the intended victim’s spoofed source IP are broadcast to a computer network using an IP broadcast address. The target of the attack is flooded with packets, causing performance to decline
DoS - Friendly/Unintentional
a DoS attack that is carried out by devices that have legitimate access to the attacked server. This can occur as part of a DDoS where the legitimate device is a botnet. It could also occur when a user inadvertently causes a DoS attack due to initialising multiple requests that hang up the server
DoS - Physical Attack
an attack where an attacker attacks a device in such a way as to permanently put it out of commission. Also referred to as permanent DoS, this attack may involve affecting the firmware or infecting the device with malware
Cable tester
Verifies that a cable is good
Crimper
Attaches media connectors to the ends of the cable
Loopback Plug
Echoes signals over a port to ensure it is working properly
Multimeter
Includes a voltmeter, an ohmmeter, and an ammeter to measure voltage, current and resistance
Punchdown Tool
Attaches cable to a patch panel
Toner Probe
Includes a tone generator and a tone locater to locate the ends of a cable
Shorts
Shorts occur when two copper connectors touch each other, resulting in current flowing through that short because the short has lower resistance. Use a cable tester to determine if a short has occurred
Opens
Opens occur when there is a break or improper termination in the cabling that prevent current from flowing through a circuit. Use a cable tester to determine if an open has occurred
Bad Connector
A bad connector will cause a connection to be unsuccessful. You can either replace the entire cable or replace the connector depending on the length of run.
Bad Wiring
Bad wiring, like a bad connector, will cause a connection to be unsuccessful. If the wiring is the problem, it is best to replace the cable
Split Pairs
A split pair is a wiring error where two wires of a twisted pair are instead connected using two wires from different pairs. It most commonly occurs when a punch-down block is wired incorrectly or when RJ-45 connectors are crimped onto the wrong wires. In both these situations, you will need to rewrite the block or connector.
Tx/Rx reversed
A straight-through cable has the same transmit (Tx) or receive (Rx) leads at each end, while they are reversed at one end in a crossover cable. A straight-through cable connects dissimilar devices, while a crossover cable connects like devices.
MDIX (Medium dependent interface crossover)
Allows a switch port to properly configure its leads as Tx or Rx. If a network device does not support MDIX you MUST use the appropriate cable
Bad SFP/GBIC module (Cable or Transceiver)
Switches can include Gigabit interface converter (GBIC) and small form-factor pluggable (SFP) modules. If one of these modules goes bad, you can either replace it if possible. Otherwise the switch will have to be replaced. To determine if the module has failed you need to use an LC loopback tester
What can effect copper cabling transmissions?
EMI/RFI, crosstalk, cable misplacement, signal attenuation and distance limitations
Physical Network Diagram
Includes cable lengths and types, server names, IP addresses, server roles, network equipment locations and number of network users. Also referred to as network maps.
Network Baseline
Includes performance statistics for your network. Without a baseline you cannot determine if performance improvements have occurred
Logical Network Diagram
Includes server roles, domain architecture, protocols used and trust relationships
Wiring Schematic
The wiring schematic emphasises the flow of the network. It includes equipment symbols and lines that indicate the flow
Procedures
Set forth steps that must be taken to enforce the network owner’s policies
Policies
Set forth the network rules, including the who, what and when of the rules. Policies tell what the rules are, who is covered by the rule and when the rule applies
Regulations
Governmental guidelines that a re written by federal or state agencies based on the laws passed by a federal or state government
Service Legal Agreement (SLA)
Defines the minimum level of service that will be provided. An SLA is often implemented between an Internet Service Provider (ISP) and the company obtaining services from the ISP
Memorandum of Understanding (MOU)
Defines the roles and parameters of an agreement between two parties. It is often not a legally binding document. Some companies will use MOUs to define services within the organisation such as the services that will be provided by the IT department
Master Service Agreement (MSA)
Specifies payment terms, product warranties, intellectual property ownership, dispute resolution and other aspects between two parties. It will be used to govern all future statements of work (SOWs) between the two parties
Disaster Recovery Plan (DRP)
A document that sets forth the policies, tools and procedures designed to enable the recovery or continuation of vital infrastructure and systems that are needed to support critical business functions. DRPs are often seen as subsets of business continuity plans
Business Continuity Plan (BCP)
A plan that is designed to ensure that the business can produce their products or continue their work at acceptable levels following a disruptive incident. Unlike a DRP a BCP targets incidents such as the loss of a key member of an organisation or how the organisation responds in the event of a device failing or something that would cause a similar network disruption
VDSL
Very high data rate Digital Subscriber Line (VDSL) provides the highest data rate at 51 to 55 megabits per second over cable lengths of up to 1000ft or 300 metres
ADSL
Asymmetric DSL (ADSL) up to 6.1Mbps downstream, up to 640Kbps upstream
HDSL / SDSL
High bit rate DSL (HDSL) and Symmetric DSL (SDSL) both provide data transmission rates up to 1.544Mbps in North America and 2.048Mbps in Europe
DSL
DSL lines use UTP/STP cabling. The maximum length for ADSL is 18,000ft. The maximum length for HDSL is 12,000ft. The maximum length for VDSL is 4,000ft. DSL is a packet-switched network
UTP Category 1 Cable
Up to 4 Mbps
UTP Category 2 Cable
Up to 4 Mbps
UTP Category 3 Cable
Up to 10 Mbps
UTP Category 4 Cable
Up to 16 Mbps
UTP Category 5 Cable
Up to 100Mbps up to 100m
UTP Category 5e Cable
Up to 1000 Mbps
UTP Category 6 Cable
Up to 1000 Mbps or 1Gbps up to 100m
UTP Category 6a Cable
Up to 10Gbps up to 100m
UTP Category 7 Cable
Up to 10Gbps up to 100m
UTP Category 8 Cable
Up to 40 Gbps and 30m, 100m when supporting 10Gbps
Types of Media Converters
- Single-mode fibre to Ethernet
- Multi-mode fibre to Ethernet
- Fibre to coaxial
- Single-mode fibre to Multi-mode fibre
DHCP Term - Lease
A single IP address that is being used by a DHCP client
DHCP Term - Option
A parameter that can be used to assign router, DNS server and other information to DHCP clients
DHCP Term - Scope
A range of possible IP addresses that a DHCP server can assign
DHCP Term - Reservation
An allocation of a single IP address to a MAC address
Loopback Interface
Allows you to test to ensure that the local network interface is working properly. The IPv4 address for the locate loopback is 127.0.0.1, and the IPv6 address for the loopback is ::1.
Routing Loop
A network problem that happens when a data packet continually loops through the same routers over and over. This is a problem associated with Distance Vector Protocols, such as RIP and RIPv2. Methods for dealing with loops include maximum hop count, split horizon, route poisoning and hold down times
Routing Table
A data table that lists the routes to particular network destinations. They can be stored on a router or a computer.
Default Route
The route that takes effect when no other route can be determined for a given destination. All pacKets for destinations not established in the routing table are sent via the default route. In most cases the default route is the router closest to the computer.
Interior Gateway Routing protocols versus Exterior Gateway Protocols
Protocols that route between autonomous systems or routing domains are referred to as Exterior Gateway Routing Protocols. Interior Gateway Protocols discover paths between networks within the same organisational boundary.
Autonomous Numbers Authority (AS)
Numbers assigned to network operators by the Internet Assigned Numbers Authority (IANA) and the Regional Internet Registries (RIRs)
Route Distribution
When you take a route from one routing protocol and distribute it to another protocol. By default routers only advertise and share routes with other routers running the same protocol.
Hot Standby Router Protocol (HSRP)
A Cisco proprietary first-hop redundancy protocol (FHRP) designed to allow for transparent fail-over of the first-hop IP router
Route Aggregation
Minimises the number of routing tables required in an IP network organising network layer IP addresses in a hierarchical way so that addresses are topologically significant.
Shortest Path Bridging (SPB)
A routing protocol that identifies loop-free shortest paths to help with traffic engineering.
Role Separation
Involves dividing server duties amongst two or more servers to reduce an attack profile.
Penetration Testing
Using hacking methodologies and tools to test the security of a clients network on behalf of the client
File Integrity Monitoring
Helps to identify unauthorised changes to files
Honeypot
A file or object on a network designed to lure in a hacker, often to divert attention from other resources
PAT
Port Address Translation provides port address translation. When using PAT you are able to share a single public IP address among multiple computers on the same network
NAT
Network Address Translation provides network address translation. This is based on the individual private IP addresses of the NAT clients
APIPA
Automatic Private IP Addressing is a private addressing scheme. In APIPA clients that are configured to obtain a dynamic IP address and cannot locate a DHCP server will assign themselves an IP address in the APIPA range (169.254.x.x)
DHCP
Dynamic Host Configuration Protocol is a dynamic IP addressing scheme whereby DHCP servers assign IP addresses based on the DHCP client requests
RFC 1918
RFC 1918 was used to create the standards for assigning IP address within a private network to various pieces of networking equipment. It facilitated the expansion of usable IP addresses under IPv4 to prevent the exhaustion of public addresses available
T1
1.544Mbps, 650ft, UTP/STP/Coaxial
T3
44.736Mbps, 450 ft, Coaxial
E1
2.048Mbps, 650ft, UTP/STP/Coaxial
E3
34.368Mbps, 450 ft, Coaxial
802.11a
5GHz, up to 54Mbps
802.11b
2.4GHz, up to 11Mbps
802.11g
2.4GHz, up to 54Mbps
802.11n
2.4/5GHz, up to 600Mbps
802.11ac
5GHz, up to 1.3Gbps
802.11ax
2.4/5/6GHz, up to 9.6Gbps
UTM
Unified threat Management - This device bundles multiple security functions into a single physical or logical device. Features included could be IPS, IDS, anti-virus, anti-malware, anti-spam, NAT and other functions
FTP
File Transfer Protocol - 20, 21
SSH, SFTP
Secure Shell, Secure File Transfer Protocol - 22
TELNET
23 - Telnet is a network protocol used to virtually access a computer and provide a two-way, collaborative and text-based communication channel between two machines. It follows a user command TCP/IP networking protocol that creates remote sessions.
SMTP
Simple Mail Transfer Protocol - TCP 25, Application Layer
DNS
Domain Name Server - 53
DHCP
Dynamic Host Configuration Protocol - 67, 68
TFTP
69 - Trivial File Transfer Protocol (TFTP) is a simple protocol that provides basic file transfer function with no user authentication.
HTTP
HyperText Transfer Protocol - 80
POP3
110 - Post Office Protocol version 3 is an email message retrieval protocol that uses TCP 110. Application layer
NTP
Network Time Protocol - UDP 123
NetBIOS
NetBIOS provides three distinct services: Name service for name registration and resolution (ports: 137/udp and 137/tcp) Datagram distribution service for connectionless communication (port: 138/udp) Session service for connection-oriented communication (port: 139/tcp)
IMAP
TCP port 143 - Internet Message Access Protocol is an internet protocol for e-mail retrieval. IMAP4 works at the application layer of the OSI model
SNMP
Simple Network Management Protocol - 161/162
LDAP
The Lightweight Directory Access Protocol (LDAP) is a vendor-neutral software protocol used to lookup information or devices within a network. Whether you want to build a central authentication server for your organization or want to simplify access to internal servers and printers, LDAP is the answer. - 389
HTTPS
HyperText Transfer Protocol Secure - 443
SMB
Server Message Block - 445 - The Server Message Block protocol (SMB protocol) is a client-server communication protocol used for sharing access to files, printers, serial ports and other resources on a network.
Syslog
System Log - 514 - a type of logging that allows a system administrator to monitor and manage logs from different parts of the system. It can be used to track events and errors, as well as provide information about system performance.
SMTP TLS
Simple Mail Transport Protocol Transport Layer Security - 587 - encrypts data as it traverses a network.
LDAPS
Lightweight Directory Access Protocol Secure - 389 - uses TLS/SSL as a transmission protocol.
IMAP over SSL
IMAP traffic travel over a secure socket to a secure port, typically TCP port 993.
POP3 over SSL
The POP3S protocol over port 995 provides for secure email downloads by using SSL/TLS encryption.
SQL Server
Structured Query Language Server - 1433 - is a programming language for storing and processing information in a relational database.
SQLnet
The SQLNET protocol is used by Oracle SQL servers to execute SQL commands from clients, including load balancing and application-specific services. Support of stateful firewall and NAT services requires that you configure the SQLNET ALG for TCP port 1521.
H.323
H. 323 is one of the oldest standards which are generally used for VoIP telephony and video conferencing. It is a system of various protocols and elements that allows transferring media data over packet networks. - 1720
MGCP
The Media Gateway Control Protocol (MGCP) is a telecommunication protocol for signaling and call control in hybrid voice over IP (VoIP) and traditional telecommunication systems. - 2427/2727
MySQL
MySQL is a relational database management system - 3306
RDP
The Remote Desktop Protocol (RDP) is a protocol, or technical standard, for using a desktop computer remotely. - 3389
RTP
Real-time Transport Protocol (RTP) is a network standard designed for transmitting audio or video data that is optimized for consistent delivery of live data. - 5004/5005
SIP
5060/5061 - The Session Initiation Protocol (SIP) is a signaling protocol used for initiating, maintaining, and terminating communication sessions that include voice, video and messaging applications. SIP is used in Internet telephony, in private IP telephone systems, as well as mobile phone calling over LTE (VoLTE).
Gateway
A gateway is used to connect networks that use different protocols
CSU/DSU
A Channel Service Unit/Digital Service Unit is a device typically required by leased lines, such as T1 lines, to terminate their media connection to your LAN
Wireless NIC
Wireless Network Interface Card is designed specifically for wireless networks. It is the piece of hardware that enables wireless communication for a computer
Device Density
The ratio of users to access points
Wireless Controller
A centralised device that can be used to manage multiple wireless access points
VLAN pooling
assigns IP addresses to wireless clients from a pool of IP subnets and their associated VLANs
Antenna Properties
Gain, Beamwidth, Transmission angle
ICMP
Internet Control Message Protocol sends error messages indicating, for example, that a requested service is not available or that a host or router could not be reached. It operates on the Internet layer of the Internet protocol suite (TCP/IP)
UDP
User Datagram Protocol sends messages, called datagrams, to other hosts on an internet protocol (IP) network without prior communications to set up special transmission channels or data paths. It operates on the Transport Layer of the internet protocol suite (TCP/IP model)
TCP
Transmission Control Protocol provides reliable, ordered and error-checked delivery of data between applications running on hosts communicating over an IP network. It operates on the Transport Layer of the internet protocol suite (TCP/IP). TCP is the protocol used by the World Wide Web, Email, Remote administration and file transfer applications
CoS
Class of Service implements packet tagging in a local area network. It tags the different types of traffic, such as video streaming or VoIP. the tag is a value between 0 and 8, with 0 being the highest priority
QoS
Quality of Service uses the CoS tag to determine which traffic gets priority but Qos does not implement the tags. Layer 3 technology that allows the network to provide increased levels of service based on the type of traffic. Can provide dedicated bandwidth and control jitter
Traffic Shaping
The overall mechanism that encompasses Cos, QoS and differentiated services
Differentiated services (Diffserv)
Uses CoS classifications for identification and subsequently utilises the QoS parameters to differentiate traffic. It is the term used for end-to-end QoS model
X.25
A WAN protocol that is used to create a continuous link between two offices. It employs switches, routes and circuits to produce the best route to transfer data at any given time
MTBF
MTBF - Mean Time Between Failures is the average, or mean time between failures on a device or system. It is an expression of reliability
MTTR
Mean Time To Recover is the average, or mean, time that it takes to recover or restore a system. In terms of a backup the term would refer to the time needed to restore a system from a full, full+incremental, or full+differential backup. The term can also be applied to full system failure or hardware component failure such as hard drive, RAM or power supply
SLA
Service Level Agreement requirements determine what the vendor who provides technology services is obligated to provide to the customer. Items that are outlined in the SLA can include response time, repair time, network reliability expectations, escalation protocols, dispute resolution and more. Often the terms MTBF and MTTR may be included in an SLA
RADIUS
RADIUS server provides authentication, authorisation and accounting, may also be referred to as AAA server
TACACS
Terminal Access Controller Access Control System is the CISCO implementation of RADIUS.
XTACACS
The second generation of TACACS and separates the authentication, authorisation and auditing processes
TACACS+
The third generation of TACACS, provides all features of XTACACS along with extended two-factor user authentication.
ipconfig /flushdns
Flushes the contents of the client computer’s DNS cache
ipconfig /all
Displays all the TCP/IP settings for the computers
ipconfig /registerdns
registers the computer’s DNS hostname with the DNS server
ipconfig /displaydns
displays the contents of the computer’s DNS cache
ipconfig /renew
command will renew the client’s DHCP lease
ipconfig /release
will release the client’s DHCP lease
ipconfig /showclassid
will display the DHCP class ID assigned to the client computer
ipconfig /setclassid
will configure the DHCP class ID for the client computer
Physical Network Diagram
Contains cable lengths and types, server names, IP addresses, server routes, server roles, network equipment locations and number of network users
Logical Network Diagram
Contains server roles, Domain architecture, protocols used and trust relationships. NOT IP addresses and server names
Wiring Schematic
Emphasises the flow of the network. It includes equipment symbols and lines that indicate the flow
BNC Connector
Coaxial Cable, can also use F connector
SC Connector
Fibre-optic cable, can also use an ST or LC connector
RJ-45 Connector
Twisted Pair Cable, RJ-45 in networks, RJ-11 in telephone deployments
IPv6 APIPA
fe80::/10
Private IPv6
fc00::/7
Loopback IPv6
::1/128
Multi-mode Fibre
Up to 10Gbps and 500m
Single-mode Fibre
Up to 10Gbps and 40km
Thicknet
Uses RG-6 coaxial cabling, up to 10Mbps and 500m
Thinnet
uses RG-59 coaxial cabling, up to 10Mbps and 185m
WEP
Wired Equivalent Privacy - Uses a 40-bit or 104-bit key
WPA/WPA2 Personal
Wifi Protected Access - Uses a 256-bit pre-shared key
WPA/WPA2 Enterprise
Wifi Protected Access - Requires a RADIUS server, For large networks
TDMA
TDMA - Time Division Multiple Access is obsolete. A 2G technology decommissioned in 2007-2009
CDMA
Code-division Multiple Access - refers to a multiplexing technique, applies to 2G and 3G, still used today
EDGE
Enhanced Data Rates for GSM Evolution is three times faster than GSM (but based on GSM technologies), Still in use
GSM
Global System for Mobile communications is the world’s most widely used cellphone technology. Still widely used today
LTE
Long Term Evolution is an IP-based 4G cellular technology rolled out in 2012
UTM
Unified Threat Management appliance provides multiple security functions in a central location. Some services/functions include load balancing, email security, URL filtration and wireless security
VoIP PBX
A Voice over IP Private Branch Exchange allows a company to use a single public-facing telephone number while having individual (extensions) for employees in a VoIP phone system
NTP
Network Time Protocol is used to synchronise the clocks of computers on the network
iptables
The iptables Linux command allows you to control a firewall and filter packets
tcpdump
The tcpdump command allows you to analyse wired or wireless network traffic on a Linux system
nslookup
The nslookup command (Linux) is used to query the DNS server. nslookup with a domain name will return the A record. nslookup with an IP address will return the ptr record
ifconfig
ifconfig (Linux) is the counterpart to the Windows ipconfig command and provides information about the network interface card
MPLS VPN
Multiprotocol Label Switching Layer 3 Virtual Private Network. This will allow all offices to connect to the same single-routed network and connect directly to the cloud
Fast Ethernet 100Base-Tx network
100 Mbps data-transmission rate, Maximum segment length of 100m, Two pairs of wires with a Cat5 UTP cabling
ESD
Electrostatic Discharge
FTP (port)
21
POP3 (port)
110
IMAP (port)
143
HTTPS (port)
443
RDP (port)
3389
SMTP (port)
25
LDAP (port)
389
APIPA IPv6
fe80::/10
Private IPv6
fc00::/7
Loopback IPv6
::1/128
VPN concentrator
Terminates VPN tunnels
LC - Lucent Connector, Fibre-optic, Small
A (DNS)
Maps a host name to an IPv4 address
AAAA (DNS)
Maps a host name to an IPv6 address
CNAME (DNS)
Maps an additional host name to an existing host record
MX (DNS)
Maps a mail server name to a domain
PTR (DNS)
Maps an IP address to a host name
CIDR values for class A
/8 - /15
CIDR values for Class C
/24 - /30
CIDR values for Class B
/16 - /23
You have been hired as a network administrator. The company wants to implement a 10 Gigabit Ethernet designation for use with SONET network. Which of the following should you implement?
10GBase-SW - for use with Synchronous Optical Networking (SONET) networks.
Network Cable (OSI Layer)
Physical -
FDDI (OSI Layer)
Data Link (Fibre Distributed Data Interface)
IPsec (OSI Layer)
Network
TCP (OSI Layer)
Transport
RPC (OSI Layer)
Session (Remote Procedure Call)
MIME (OSI Layer)
Presentation (Multipurpose Internet Mail Extensions, allows users to send a variety of file types in an email inc images, videos, audio and apps)
DHCP (OSI Layer)
Application (Dynamic Host Configuration Protocol, Operates layer 7 but sends data relating to layers 2 and 3)
ping -i
enables you to specify the size of the messages sent to the target. eg
- ping 10.0.0.1 -I 2048 -n 11 sends 2048 bytes
ping -n
enables you to specify the number of messages the ping tool should transmit eg
- ping 10.0.0.1 -l 2048 -n 11 will send 11 messages
ping -t
causes the ping tool to transmit messages until manually halted
