Mike Meyers Network + terms

3G

Third generation wireless data standard for cell phones and other mobile devices. 3G matured over time until Evolved High-Speed Packet Access (HSPA+) became the final wireless 3G data standard. It transferred at theoretical maximum speeds up to 168 megabits per second (Mbps), although real-world implementations rarely passed 10 Mbps.

4G

Most popularly implemented as Long Term Evolution (LTE), a wireless data standard with theoretical download speeds of 300 Mbps and upload speeds of 75 Mbps.

4to6

Internet connectivity technology that encapsulates IPv4 traffic into an IPv6 tunnel to get to an IPv6 address

6in4

An IPv6 tunneling standard that can go through IPv4 Network Address Translation (NAT)

6to4

An IPv6 tunneling protocol that doesn't require a tunnel broker. It is generally used to directly connect two routers because it normally requires a public IPv4 address

8 Position 8 Contact (8P8C)

Four-pair connector used on the end of network cable. Often erroneously referred to as an RJ-45 connector

10 Gigabit Ethernet (10GbE)

A very fast Ethernet designation, with a number of fiber-optic and copper standards

10base2

The last true bus-standard network where nodes connected to a common, shared length of coaxial cable.

10BaseFL

Fiber-optic implementation of Ethernet that runs at 10 Mbps using baseband signaling. Maximum segment length is 2 km.

10BaseT

An Ethernet LAN designed to run on UTP cabling. Runs at 10 Mbps and uses baseband signaling. Maximum length for the cabling between the NIC and the hub (or the switch, the repeater, and so forth) is 100 m.

10BaseER/10GBaseEW

A 10 GbE standard using 1550-nm single-mode fiber. Maximum cable length up to 40 km

10GBaseLR/10GBaseLW

A 10 GbE standard using 1310-nm single-mode fiber. Maximum cable length up to 10 km.

10GBaseSR/10GBaseSW

A 10 GbE standard using 850-nm multimode fiber. Maximum cable length up to 300 m.

10GBaseT

A 10 GbE standard designed to run on CAT 6a UTP cabling. Maximum cable length of 100 m.

66 block

Patch panel used in telephone networks; displaced by 110 blocks in networking

100BaseFX

An Ethernet LAN designed to run on fiber-optic cabling. Runs at 100 Mbps and uses baseband signaling. Maximum cable length is 400 m for half-duplex and 2 km for full-duplex.

100BaseT

An Ethernet LAN designed to run on UTP cabling. Runs at 100 Mbps, uses baseband signaling, and uses two pairs of wires on CAT 5 or better cabling.

100BaseT4

An Ethernet LAN designed to run on UTP cabling. Runs at 100 Mbps and uses four-pair CAT 3 or better cabling. Made obsolete by 100BaseT.

100BaseTX

The technically accurate but little-used name for 100BaseT.

110 block

Also known as a 110-punchdown block, a connection gridwork used to link UTP and STP cables behind an RJ-45 patch panel.

110-punchdown block

The most common connection used on the back of an RJ-45 jack and patch panels.

110-Punchdown Tool

See Punchdown Tool.

802 committee

The IEEE committee responsible for all Ethernet standards.

802.1X

A port-authentication network access control mechanism for networks.

802.3 (Ethernet)

See Ethernet.

802.3ab

The IEEE standard for 1000BaseT.

802.3z

The umbrella IEEE standard for all versions of Gigabit Ethernet other than 1000BaseT.

802.11

See IEEE 802.11.

802.11a

Wireless networking standard that operates in the 5-GHz band with a theoretical maximum throughput of 54 Mbps.

802.11ac

A wireless standard that operates at 5GHz and claims to provide wireless speeds of 1Gbps or higher.

802.11a-ht

Along with the corresponding 802.11g-ht standard, technical terms for mixed mode 802.11a/802.11g operation. In mixed-mode, both technologies are simultaneously supported.

802.11b

The first popular wireless standard, operates in the frequency range of 2.4 GHz and offers throughput of up to 11 Mbps

802.11g

Older wireless standard that operates on the 2.4-GHz band with a maximum throughput of 54 Mbps. Superseded by 802.11n

802.11g-ht

Along with the corresponding 802.11a-ht standard, technical terms for mixed mode 802.11a/802.11g operation. In mixed mode, both technologies are simultaneously supported

802.11i

A wireless standard that added security features.

802.11n

An 802.11 standard that increases the transfer speeds and adds support for multiple in/multiple out (MIMO) by using multiple antennas. 802.11n can operate on either the 2.4 or 5-GHz frequency band and has a maximum throughput of 400 Mbps. Superseded by 802.11ac

802.16

See IEEE 802.16

1000BaseCX

A Gigabit Ethernet standard using unique copper cabling, with a 25-m maximum cable distance.

1000BaseLX

A Gigabit Ethernet standard using single-mode fiber cabling, with a 5-km maximum cable distance.

1000BaseSX

A Gigabit Ethernet standard using multimode fiber cabling, with a 220- to 500-m maximum cable distance.

1000BaseT

A Gigabit Ethernet standard using CAT 5e/6 UTP cabling, with a 100-m maximum cable distance.

1000BaseTX

Short-lived gigabit-over-UTP standard from TIA/EIA. Considered a competitor to 1000BaseT, it was simpler to implement but required the use of CAT 6 cable.

1000BaseX

An umbrella Gigabit Ethernet standard. Also known as 802.3z. Comprises all Gigabit standards with the exception of 1000BaseT, which is under the 802.3ab standard.

A records

DNS records that map host names to their IPv4 addresses

AAA (authentication, authorization, and accounting)

See authentication, authorization, and accounting

AAAA records

DNS records that map host names to their IPv6 addresses

absorption

Quality of some building materials (such as brick, sheetrock and wood) to reduce or eliminate a Wi-Fi signal

acceptable use policy

A document that defines what a person may and may not do on an organization's computers and networks.

access control

All-encompassing term that defines the degree of permission granted to use a particular resource. That resource may be anything from a switch port to a particular file to a physical door within a building.

access control list (ACL)

A clearly defined list of permissions that specifies what actions an authenticated user may perform on a shared resource.

Access Control Server (ACS)

Cisco program/process/server that makes the decision to admit or deny a node based on posture assessment. From there, the ACS directs the edge access device to allow a connection or to implement a denial or redirect.

access port

Regular port in a switch that has been configured as part of a VLAN. Access ports are ports that hosts connect to. They are the opposite of a trunk port, which is only connected to a trunk port on another switch.

Active directrory

A form of directory service used in networks with Windows servers. Creates an organization of related computers that share one or more Windows domains

activity light

An LED on a NIC, hub, or switch that blinks rapidly to show data transfers over the network.

ad hoc mode

A wireless networking mode where each node is in direct contact with every other node in a decentralized free-for-all. Ad hoc mode is similar to the mesh topology.

Adaptive Network Technology (ANT+)

A low-speed, low-power networking technology; used in place of Bluetooth for connecting devices, such as smart phones and exercise machines

Address Resolution Protocol (ARP)

A protocol in the TCP/IP suite used with the command-line utility of the same name to determine the MAC address that corresponds to a particular IP address

administrative accounts

Specialized user accounts that have been granted sufficient access rights and authority to manage specified administrative tasks. Some administrative accounts exist as a default of the system and have all authority throughout the system. Others must be explicitly assigned the necessary powers to administer given resources.

ADSL (asymmetric digital subscriber line)

See Asymmetric Digital Subscriber Line (ADSL).

Advanced Encryption Standard (AES)

A block cipher created in the late 1990s that uses a 128-bit block size and a 128-, 192-, or 256-bit key size. Practically uncrackable.

adware

A program that monitors the types of Web sites you frequent and uses that information to generate targeted advertisements, usually pop-up windows.

agent

In terms of posture assessment, refers to a client that has its posture checked and presented by non-permanent software, such as a Web app program, that executes as part of the connection process. Agentless software does not run directly within the client but is run on behalf of the client

aggregation

A router hierarchy in which every router underneath a higher router always uses a subnet of that router's existing routes.

air gap

The act of physically separating a network from every other network.

Aircrack-ng

An open source tool for penetration testing many aspects of wireless networks.

alert

Proactive message sent from an SNMP manager as a result of a trap issued by an agent. Alerts may be sent as e-mail, SMS message, voicemail, or other avenue

algorithm

Set of rules for solving a problem in a given number of steps.

allow

Permission for data or communication to pass through or to access a resource. Specific allowances through a firewall are called exceptions.

American Registry for Internet Numbers (ARIN)

A Regional Internet Registry (RIR) that parcels out IP addresses to large ISPs and major corporations in North America

amplification

The aspect of a DoS attack that makes a server do a lof of processing and responding

amplified DOS attack

The type of DoS attack that sends a small amount of traffic to a server, which produces a much larger response from the server that is sent to a spoofed IP address, overwhelming a victim machine

Angled Physical Contact (APC)

Fiber-optic connector that makes physical contact between two fiber-optic cables. It specifies an 8-degree angle to the curved end, lowering signal loss. APC connectors have less connection degradation from multiple insertions compared to other connectors.

anti-malware program

Software that attempts to block several types of threats to a client including viruses, Trojan horses, worms, and other unapproved software installation and execution.

antivirus

Software that attempts to prevent viruses from installing or executing on a client. Some antivirus software may also attempt to remove the virus or eradicate the effects of a virus after an infection.

anycast

A method of addressing groups of computers as though they were a single computer. Anycasting starts by giving a number of computers (or clusters of computers) the same IP address. Advanced routers then send incoming packets to the closest of the computers.

Apache HTTP Server

An open source HTTP server program that runs on a wide variety of operating systems.

Application layer

See Open System Interconnection (OSI) Seven-Layer Model.

application log

Tracks application events, such as when an application opens or closes. Different types of application logs record different events.

Application Programming Interface (API)

Shared functions, subroutines, and libraries that allow programs on a machine to communicate with the OS and other programs.

application/context aware

Advanced feature of some stateful firewalls where the content of the data is inspected to ensure it comes from, or is destined for, an appropriate application. Context-aware firewalls look both deeply and more broadly to ensure that the data content and other aspects of the packet are appropriate to the data transfer being conducted. Packets that fall outside these awareness criteria are denied by the firewall.

approval process

One or more decision makers consider a proposed change and the impact of the change, including funding. If the change, the impact, and the funding are acceptable, the change is permitted.

archive

The creation and storage of retrievable copies of electronic data for legal and functional purposes

archive bit

An attribute of a file that shows whether the file has been backed up since the last change. Each time a file is opened, changed, or saved, the archive bit is turned on. Some types of backups turn off the archive bit to indicate that a good backup of the file exists on tape.

Area ID

Address assigned to routers in an OSPF network to prevent flooding beyond the routers in that particular network. See also Open Shortest Path First (OSPF)

areas

Groups of logically associated OSPF routers designed to maximize routing efficiency while keeping the amount of broadcast traffic well managed. Areas are assigned a 32-bit value that manifests as an integer between 0 and 4294967295 or can take a form similar to an IP address, for example, "0.0.0.0."

ARP

See Address Resolution Protocol (ARP).

ARP cache poisoning

A man-in-the-middle attack, where the attacker associates his MAC address with someone else's IP address (almost always the router), so all traffic will be sent to him first. The attacker sends out unsolicited ARPs, which can either be requests or replies.

arping

A command used to discover hosts on a network, similar to ping, but that relies on ARP rather than ICMP. The arping command won't cross any routers, so it will only work within a broadcast domain. See also Address Resolution Protocol (ARP) and ping.

asset disposal

Reusing, repurposing or recycling computing devices that follows system life cycle policies in many organizations

asset management

Managing each aspect of a network, from documentation to performance to hardware.

Asymmetric Digital Subscriber Line (ADSL)

A fully digital, dedicated connection to the telephone system that provides download speeds of up to 9 Mbps and upload speeds of up to 1 Mbps.

Asymmetric-Key Algorithm

An encryption method in which the key used to encrypt a message and the key used to decrypt it are different, or asymmetrical.

Asynchronous Transfer Mode (ATM)

A network technology that runs at speeds between 25 and 622 Mbps using fiber-optic cabling or CAT 5 or better UTP.

attenuation

A process that proves good data traffic truly came from where it says it originated by verifying the sending and receiving users and computers

Authentication, Authorization, and Accounting (AAA)

A security philosophy wherein a computer trying to connect to a network must first present some form of credential in order to be authenticated and then must have limitable permissions within the network. The authenticating server should also record session information about the client

authentication server (AS)

In Kerberos, a system that hands out Ticket-Granting Tickets to clients after comparing the client hash to its own. see also Ticket-Granting Ticket (TGT)

authoritative DNS servers

DNS servers that hold the IP addresses and names of systems for a particular domain or domains in special storage areas called forward lookup zones. they also have reverse lockup zones

Authoritative Name Server

Another name for Authoritative DNS servers.

authorization

A step in the AAA philosophy during which a client's permissions are decided upon

Autonomous System (AS)

One or more networks that are governed by a single protocol, which provides routing for the Internet backbone.