Chapter 8

FTP (File Transfer Protocol)

A TCP/IP protocol and application that uses the Internet to transfer files between two computers. used to transfer files between two computers over a WAN or LAN connection.

Telnet

A TCP/IP protocol and application used to allow an administrator or other user to control a computer remotely. used by this client/server applications to allow an administrator or other user to control a computer remotely. This is not considered secure because transmissions in Telnet are not encrypted.

connectionless protocol or best-effort protocol

A TCP/IP protocol such as UDP that works at the OSI Transport layer and does not guarantee delivery by first connecting and checking where data is received. It might be used for broadcasting, such as streaming video or sound over the web, where guaranteed delivery is not as important as fast transmission. Also called a best-effort protocol. Also see UDP (User Datagram Protocol).connectionless protocol

IMAP4 (Internet Message Access Protocol, version 4)

A TCP/IP protocol used by an email server and client that allows the client to manage email stored on the server without downloading the email. Compare with POP3.

Lightweight Directory Access Protocol (LDAP)

A TCP/IP protocol used by client applications to query and receive data from a database. The LDAP protocol does not include encryption. For example, an email client on a corporate network might query a database that contains the email addresses for all employees, or an application might query a database of printers looking for a printer on the corporate network or the Internet.

SMTP (Simple Mail Transfer Protocol)

A TCP/IP protocol used by email clients to send email messages to an email server and on to the recipient's email server. Also see POP and IMAP.

shielded twisted-pair (STP) cable

A cable that is made of one or more twisted pairs of wires and is surrounded by a metal shield.

crossover cable

A cable used to connect two like devices such as a hub to a hub or a computer to a computer (to make the simplest network of all). The transmit connectors at one end of the cable are wired as the receiving connectors at the other end of the cable and vice versa.

file server

A computer dedicated to storing and serving up data files and folders. stores files and makes them available to other computers. A network administrator can make sure this data is backed up regularly and kept secure.

proxy server

A computer that intercepts requests that a client (for example, a browser) makes of a server (for example, a web server). A proxy server can serve up the request from a cache it maintains to improve performance or it can filter requests to secure a large network.

endpoint devices

A computer, laptop, smartphone, printer, or other host on a network

Unified Threat Management (UTM)

A computer, security appliance, network appliance, or Internet appliance that stands between the Internet and a private network. This device runs a firewall, anti-malware software, and other software to protect the network, and is considered a next-generation firewall.

UDP (User Datagram Protocol)

A connectionless TCP/IP protocol that works at the OSI Transport layer and does not require a connection to send a packet or guarantee that the packet arrives at its destination. The protocol is commonly used for broadcasting to multiple nodes on a network or the Internet. Compare with TCP (Transmission Control Protocol).

PoE injector

A device that adds power to an Ethernet cable so the cable can provide power to a device.

patch panel

A device that provides multiple network ports for cables that converge in one location such as an electrical closet or server room.

CIFS (Common Internet File System)

A file access protocol and the cross-platform version of SMB used between Windows, Linux, macOS, and other operating systems. CIFS is a spinoff of the SMB2 protocol.

next-generation firewall (NGFW)

A firewall that combines firewall software with anti-malware software and other software that protects resources on a network. combines firewall functions with antivirus/anti-malware functions and perhaps other functions as well.

subnet

A group of local networks tied together in a subsystem of the larger intranet. In TCP/IP version 6, this is one or more links that have the same 16 bits in the subnet ID of the IP address. See subnet ID. created to subdivide a network into smaller networks so that fewer devices receive and respond to broadcast messages.

crimper

A hand tool used to attach a terminator or connector to the end of a cable. It applies force to pinch the connector to the wires in the cable to securely make a solid connection.

cable stripper

A hand tool used to cut away the plastic jacket or coating around the wires of a network cable.

punchdown tool

A hand tool used to punch individual wires from a network cable into their slots to terminate the cable.

fully qualified domain name (FQDN)

A host name and domain name that identifies a computer and the network to which it belongs. For example, joesmith.mycompany.com is an FQDN. An FQDN is sometimes loosely referred to as a domain name.

PDU (protocol data unit)

A message on a TCP/IP network. This might be called a packet or frame, depending on the complexity of this. messages with IP address header information added are called packets. Messages with source and destination MAC addresses are called frames. In general, all of these messages can be referred to with this more technical term

broadcast message

A message sent over a local network to all devices on the network; the message does not contain recipient information. 255.255.255.255

OSI (Open Systems Interconnection) model

A model for understanding and developing computer-to-computer communication that divides networking functions among seven layers: Physical, Data Link, Network, Transport, Session, Presentation, and Application.

network multimeter

A multifunctional tool that can test network connections, cables, ports, and network adapter When you connect it to your network, it can also detect the Ethernet speed, duplex status, default router on the network, lengths of cables, voltage levels of PoE, and other network statistics and details. Many of these can document test results and upload results to a computer. Good of these can cost several hundred dollars.

host name

A name that identifies a computer, printer, or other device on a network; the host name can be used instead of the computer's IP address to address the computer on the network. The host name together with the domain name is called the fully qualified domain name. Also called computer name.

domain name

A name that identifies a network and appears before the period in a website address, such as microsoft.com. A fully qualified domain name is sometimes loosely called a domain name. Also see fully qualified domain name.

hub

A network device or box that provides a central location to connect cables and distributes incoming data packets to all other devices connected to it. Compare with switch. transmits the message to every device except the device that sent the message

repeater

A networking device that amplifies and retransmits a wireless signal to a wider coverage area and uses a new network name for the rebroadcast.

bridge

A networking device that stands between two segments of a network and manages traffic between them.

CAT-5e

A popular rating used for UTP cables and rated for Fast Ethernet and Gigabit Ethernet. Cable System:10/100BaseT, Gigabit Ethernet Frequency:Up to 350 MHz

Syslog

A protocol that collects event information about network devices, such as errors, failures, and users logging in or out, and sends the information to a Syslog server. a protocol that gathers event information about various network devices, such as errors, failures, maintenance tasks, and users logging in or out. The messages about these events are sent to a central location called a Syslog server, which collects the events into a database.

Server Message Block (SMB)

A protocol used by Windows to share files and printers on a network.

Secure Shell (SSH)

A protocol used to pass login information to a remote computer and control that computer over a network using encryption. encrypts communications so hackers can't read the data if they intercept a transmission. This is used in various situations for encryption, such as when remotely controlling a computer or when communicating with a web server. This is commonly used in Linux to pass sign-in information to a remote computer and control that computer over a network. Because it's secure, This is preferred over Telnet.

CAT-5

A rating used for UTP cables and rated for Fast Ethernet, but seldom used today. Cable system: 10/100BaseT Frequency: Up to 100 MHz

CAT-6

A rating used for twisted-pair cables that have less crosstalk than CAT-5e cables. These cables might contain a plastic cord down the center that helps to prevent crosstalk, but they are less flexible and more difficult to install than CAT-5e. Cable system: 10/100BaseT, Gigabit Ethernet, 10Gig Ethernet at shorter distances Frequency:Up to 250 MHz

authentication server

A server responsible for authenticating users or computers to the network so they can access network resources.

endpoint management server

A server that monitors various endpoint devices on the network to ensure that endpoints are compliant with security requirements such as anti-malware and that OS updates are applied

Syslog server

A server that receives and analyzes syslog data to monitor network devices and create alerts when problems arise that need attention.

CIDR (Classless Interdomain Routing) notation

A shorthand notation (pronounced "cider notation") for expressing an IPv4 address and subnet mask; the IP address is followed by a slash (/) and the number of bits in the IP address that identifies the network—for example, 15.50.35.10/20. Sometimes an IP address and subnet mask are written using a shorthand notation like 15.50.212.59/20, where the /20 means that the first 20 bits in the IP address identify the network. This notation is sometimes called slash notation or this.

virtual LANs (VLANs)

A subnet of a larger network created to reduce network traffic. Managed switches are commonly used to set up this

managed switch

A switch that has firmware that can be configured to monitor, manage, and prioritize network traffic. It's appropriate for larger networks and can be used to manage QoS for prioritizing network traffic and to control speeds for specific ports.

unmanaged switch

A switch that requires no setup or configuration. Compare with managed switch. requires no setup or configuration other than connecting network cables to its ports. It does not require an IP address and is appropriate for SOHO networks.

NAT (Network Address Translation)

A technique that substitutes the public IP address of the router for the private IP address of a computer on a private network when the computer needs to communicate on the Internet.

cable tester

A tool used to test a cable to find out if it is good or to identify a cable that is not labeled.

tone generator and probe

A two-part kit used to find cables in the walls of a building. The toner connects to one end of the cable and puts out a pulsating tone that the probe can sense. Also called a toner probe or tone probe.

Simple Network Management Protocol (SNMP)

A versatile TCP/IP protocol used to monitor network traffic and manage network devices. This server works with these agents installed on devices being monitored. a versatile protocol used to monitor network traffic and manage network devices. It can help create logs for monitoring device and network performance, it can make some automatic changes to devices being monitored, and it can be used to alert network technicians when a bottleneck or other performance issues are causing problems on the network.

Gigabit Ethernet

A version of Ethernet that supports rates of data transfer up to 1 gigabit per second. becoming the most popular choice for LAN technology. Because it can use the same cabling and connectors as Fast Ethernet, a company can upgrade from Fast Ethernet to Gigabit without rewiring the network.

loopback address

An IP address that indicates your own computer and is used to test TCP/IP configuration on the computer. 127.0.0.1

AFP (Apple Filing Protocol)

An outdated file access protocol used by early editions of macOS by Apple; This is one protocol in the suite of AppleTalk networking protocols.

node

Any device that connects to the network, such as a computer, printer, or router. any device that connects to the network, such as a computer, printer, or router. The connection can be a logical attachment, such as when a virtual machine connects to the network, or a physical attachment, such as when a network adapter connects to the wired network.

Intranet

Any private network that uses TCP/IP protocols. A large enterprise might support this that is made up of several local networks.

Twisted-pair cabling

Cabling, such as a network cable, that uses pairs of wires twisted together to reduce crosstalk.

BNC connector

Coaxial cable, an older cable typically used for cable TV, uses this.

Wi-Fi analyzer

Hardware and/or software that monitors a Wi-Fi network to detect devices not authorized to use the network, identify attempts to hack transmissions, or detect performance and security vulnerabilities.

print server

Hardware or software that manages the print jobs sent to one or more printers on a network. manages network printers and makes them available to computers throughout the network. Expensive network printers can handle high-capacity print jobs from many sources, eliminating the need for a desktop printer at each workstation.

subnet mask

How does it know how many bits in its IP address identify its network? That's the job of the this.

public IP address

In TCP/IP version 4, an IP address available to the Internet.

Private IP address

In TCP/IP version 4, an IP address used on a private network that is isolated from the Internet.

octet

In TCP/IP version 4, each of the four numbers that are separated by periods and make up a 32-bit IP address. One octet is 8 bits.

multicast address

In TCP/IP version 6, an IP address used when packets are delivered to a group of nodes on a network. used to deliver messages to all nodes in a targeted, multicast group, such as when video is streaming from a server to multiple nodes on a network.

unique local address

In TCP/IP version 6, an address used to identify a specific site within a large organization. It can work on multiple links within the same organization. The address is a hybrid between a global unicast address that works on the Internet and a link local unicast address that works on only one link.

interface ID

In TCP/IP version 6, the last 64 bits or 4 blocks of an IP address that identify the interface. The last 64 bits or 4 blocks of an IPv6 address identify the interface and are called this or interface identifier. These 64 bits uniquely identify an interface on the local network.

subnet ID

In TCP/IP version 6, the last block (16 bits) in the 64-bit prefix of an IP address. The subnet is identified using some or all of these 16 bits.

Neighbors

In TCP/IP version 6, two or more nodes on the same link.

TCP/IP Model

In networking theory, a simple model used to divide network communication into four layers. This model is simpler than the OSI model, which uses seven layers. layer 1:link layer - Mac addresses Layer 2: Internet layer- IP addresses Layer 3: Transport layer - Port numbers Layer 4: Application layer

connection-oriented protocol

In networking, a TCP/IP protocol that confirms a good connection has been made before transmitting data to the other end, verifies that data was received, and resends data if it was not received. An example of this is TCP.

intrusion detection system (IDS)

Software that monitors all network traffic and creates alerts when suspicious activity happens. This software can run on a UTM appliance, router, server, or workstation.

intrusion prevention system (IPS)

Software that monitors and logs suspicious activity on a network and can prevent the threatening traffic from burrowing into the system. Compare with IDS (intrusion detection system).

T568A

Standards for wiring twisted-pair network cabling and RJ-45 connectors; in this, the green pair of wires is connected to pins 1 and 2 and the orange pair is connected to pins 3 and 6.

T568B

Standards for wiring twisted-pair network cabling and RJ-45 connectors; in this, the orange pair of wires uses pins 1 and 2 and the green pair is connected to pins 3 and 6.

HTTPS (HTTP Secure)

The HTTP protocol working with a security protocol such as Secure Sockets Layer (SSL) or Transport Layer Security (TLS) to create a secured socket that includes data encryption. TLS is better than SSL.

POP3 (Post Office Protocol, version 3)

The TCP/IP protocol that an email server and client use when the client requests the downloading of email messages. The most recent version is POP version 3. Compare with IMAP4.

HTTP (Hypertext Transfer Protocol)

The TCP/IP protocol used for the World Wide Web and used by web browsers and web servers to communicate. You can see when a browser is using this protocol by looking for this at the beginning of a URL in the address bar, such as http://www.microsoft.com.

RDP (Remote Desktop Protocol)

The Windows protocol used by Remote Desktop and Remote Assistance utilities to connect to and control a remote computer.

plenums

The area between floors of a building.

network ID

The leftmost bits in an IP address. The rightmost bits of the IP address identify the host. All the IP addresses assigned to a local network or subnet have matching bits in the first part of the IP address; these bits identify the network and are called this. For example, the range of IP addresses assigned to a local network might be 192.168.80.1-100. The first three octets (192.168.80) identify the network and the last octet (1 through 100) identifies each host. The last bits in each IP address that identify the host must be unique for each IP address on the network.

IP (Internet Protocol)

The primary TCP/IP protocol, used by the Internet layer, that is responsible for getting a message to a destination host. In the OSI model, the Internet layer is called the Network layer. The primary protocol used at the Internet layer is this, which uses a 32-bit and/or 128-bit IP address to identify each host. (Other Internet layer protocols include EIGRP, OSPF, BGP, and ICMP.) IP adds address information to the message and then passes it down to the Link layer.

PVC (polyvinyl chloride)

The product used to cover Ethernet cables; it is not safe to be used in a plenum because it gives off toxic fumes when burned.

TCP (Transmission Control Protocol)

The protocol in the TCP/IP suite of protocols that works at the OSI Transport layer, establishes a session or connection between parties, and guarantees packet delivery.

Fast Ethernet

This improved version of Ethernet, operates at 100 Mbps and typically uses copper cabling rated CAT-5 or higher. these networks can support slower speeds of 10 Mbps so devices that run at either 10 Mbps or 100 Mbps can coexist on the same LAN.

UTP (Unshielded Twisted Pair) cable

Twisted-pair networking cable commonly used on LANs that is less expensive than STP cable and does not contain shielding to prevent electromagnetic interference.

straight-through cable

Two types of network cables can be used when building a network: this and a crossover cable. An Ethernet cable used to connect a computer to a switch or other network device. Also called a patch cable.

anycast address

Using TCP/IP version 6, a type of IP address used by routers that identifies multiple destinations. Packets are delivered to the closest destination.

unicast address

Using TCP/IP version 6, an IP address assigned to a single node on a network.

DNS client

When Windows queries the DNS server for name resolution, which means to find an IP address for a computer when the fully qualified domain name is known.

socket

a connection between a browser and web server.

Power over Ethernet (PoE)

a feature that might be available on high-end wired network adapters to allow power to be transmitted over Ethernet cable. Using this feature, you can place a wireless access point, webcam, IP phone, or other device that needs power in a position in a building where you don't have an electrical outlet.

link

a local area network (LAN) or wide area network (WAN) In TCP/IP version 6, a local area network or wide area network bounded by routers. Also called local link.

link local address

also called a link local unicast address or local address, can be used for limited communication with neighboring nodes in the same link (the local network). These local addresses are similar to IPv4 APIPA addresses in that they are assigned to the computer by itself as opposed to coming from a DHCPv6 server, and are not guaranteed to be unique on the network.

TCP/IP (Transmission Control Protocol/Internet Protocol)

for almost all networks today, including the Internet, the group or suite of protocols used is called this

switch

smarter and more efficient than a hub because it keeps a table of all the MAC addresses for devices connected to it. When this receives a message, it searches its MAC address table for the destination MAC address of the message and sends the message only to the interface for the device using this MAC address

powerline networking or Ethernet over Power (EoP)

the technology that allows Ethernet transmissions over power lines in a building. A powerline adapter is plugged into the electrical circuit(s) at both ends and the adapters connect to the Ethernet network. Because the transmissions are not contained, encryption is required for security. uses power lines in a building to transmit data. this is simple to set up, inexpensive, and can run at Gigabit speeds. Like Wi-Fi, the data is sent out on a network that you cannot necessarily contain because power lines are not confined to a single building. If a building or apartment is sharing a phase (electrical signal) with another building or apartment, the data might leak and be intercepted by a neighbor.