Test ch. 6-8 Flashcards
What is a Default Gateway?
In a TCP/IP network, the IP address of the router that interconnects the LAN to a wider network, usually the Internet. This router’s IP address is part of the necessary TCP/IP configuration for communicating with multiple networks using IP.
What is NAT?
Network Address Translation - A means of translating a system’s IP address into another IP address before sending it out to a larger network. NAT manifests itself by a NAT program that runs on a system or a router. A network using NAT provides the systems on the network with private IP addresses. The system running the NAT software has two interfaces: one connected to the network and the other connected to the larger network.
The NAT program takes packets from the client systems bound for the larger network and translates their internal private IP Addresses to its own public IP address, enabling many systems to share a single IP address.
When subnetting, do not think of each subnet mask in dotted decimal, rather work with it in binary and another notation that uses a slash and is named for the method of generating blocks of IP addresses.
CIDR
Every IP node on a network has a routing table.
True
Routers work primarily with the source IP address of each packet.
False
Nat is the same as routing.
False
At which layer of the OSI model do routers work?
Network
The process of installing a large structured cabling system is so simple and logical that even a novice network tech can do it, following the published guidelines.
False
Which of the following is not an accurate description of the differences in stranded core and solid core cabling.
Stranded core is UTP while solid core is fiber-optic cabling.
Which of the following IP addresses is an APIPA address?
169.254.1.30
What network protocol do Linux and Apple (Macintosh) systems most commonly use today?
TCP/IP
Of the following, which would probably not be true of a network that occupies multiple stories of a large building?
one telecommunications room supporting the entire network
What is structured cabling?
Standards defined by the TIA/EIA that define methods of organizing the cables in a network for ease of repair and replacement.
Name 3 important elements of basic structured cabling network.
- Telecommunications room
- Horizontal Cabling
- Work Area
What is the telecommunications room?
Equipment goes in here. All cables run horizontally from here. IDF (intermediate distribution frame)
What is horizontal cabling?
Cabling that connects the equipment room to the work areas.
What is a run?
A single piece of of installed horizontal cabling.
What is the work area?
An office or cubicle that contains a PC and telephone.
Who sets the standards fo cabling?
TIA/EIA
What is solid core?
Uses a single solid wire, better conductor, but stiff and will break if handled too much. TIA/EIA says horizontal cabling should be solid core.
What is stranded core?
Each wire is a bundle of tiny wire strands. Not as good as a conductor as solid core, but handles more handling without breaking.
Equipment racks
All equipment racks are 19 inches wide. Vary in height.
What is a patch panel?
A box with a row of female connectors (ports) in the front and permanent connections in the back, to which you connect the horizontal cables.
What is a 110 block?
Also called a 110-punchdown block. A connector for a patch panel. Use a punchdown tool.
What is a patch cable?
Short, UTP cables. Stranded. Patch cables add extra distance between the switch and the PC.
What is a demarc?
Connections from the outside world that come into a building at a location. aka demarcation point.
What is a NIU?
Network Interface Unit. In a private home, the DSL or cable modem supplied by your ISP.
What is a smart jack?
Special NIU that determines if the customer has disconnected from the NIU. Set up a remote loopback - critical for loopback testing when you’re at one end of the connection and the other connection is blocks or even miles away.
Demarc Extension
Any cabling that runs from the network interface to whatever box is used by the customer as a demarc.
Multiplexer
A device that merges information from multiple input channels to a single output channel.
Vertical cross-connect
The main patch panel.
MDF
Main Distribution Frame. Stores all the equipment.
Cable Drop
The location where the cable comes out of the wall in the workstation.
Raceways
Products that adhere to the wall. Running cables along the walls.
Determining the Telecommunications room
- Distance - Won’t require cable runs longer than 90 meters.
- Power - Make sure there is enough power.
- Humidity - none
- Cooling - Keep cool
- Access - only authorized people
Continuity
A complete, functioning connection
Cable tester
A generic name for a device that tests cables. Some common tests are continuity, electrical shorts, crossed wires or other electrical characteristics.
Near-end Crosstalk
NEXT
Far-end Crosstalk
FEXT
Attenuation
A signal progresses down a piece of wire and becomes weaker.
Cable Certifiers
A powerful cable testing device used by professional installers to test the electrical characteristics of a cable and then generate a certification repot, proving that cable runs pass TIA/EIA standards
OTDR
Optical Time Domain Reflector - determines continuity and breaks
Loopback test
Sends data out of the NIC and checks to see if it comes back.
UPS
Uninterruptible Power Supply
Toner
tone generator and tone probe
IP
Internet Protocol - works at the Internet layer, taking data chunks from the Transport layer, adding addressing, and creating the final IP packet.
IPv4
Internet Protocol version 4, Typical IP address: 192.168.1.115
IPv6
Internet Protocol version6, longer address
ICMP
Internet Control Message Protocol, used with Ping
RTT
Round Trip Time or Real Transfer Time
Internet Layer
IPv4, IPv6, ICMP
IP Address
The numeric address of a computer connected to a TCP/IP network, such as the Internet. IPv4 addresses are 32 bits long, written as four octets of 8-bit binary. IPv6 addresses are 128 bits long, written as eight sets of four hexadecimal characters. IP addresses must be matched with a valid subnet mask, which identifies the part of the IP address that is the network ID and the part that is the host ID.
IP addresses are part of the Network/Internet layer
True
TTL
Time To Live
Connection-oriented
TCP - Transmission Control Protocol, use when you want to make sure it gets there in good order
Connectionless
UDP - User Datagram Protocol, not a big deal to miss a bit or two.
Continuity tester
Inexpensive network tester that can only test for continuity on a line.
Wiremap
Term that techs use to refer to the proper connectivity of wires in a network.
Time Domain Reflector
TDR - Advanced cable tester that tests the length of cables and their continuity or discontinuity, and identifies the location of any discontinuity due to a bend, break, unwanted crimp, and so on.
Subnet Mask
The value used in TCP/IP settings to divide the IP address of a host into its component parts: network ID and host ID. A string of ones followed by some number of zeros, always exactly 32 bits, typed into every TCP/IP host.
CIDR
Classless Inter-Domain Routing - Method of categorizing IP addresses inorder to distribute them
Subnetting
Taking a single class of IP addresses and chopping it into multiple smaller groups.
Dotted Decimal Notation
Shorthand method for discussing and configuring binary IP addresses.
ipconfig
A command-line utility for Windows that displays the current TCP/IP configuration of the machine; similar to UNIC/Linux’s ifconfig.
ifconfig
A command-line utility for Linux servers and workstation that displays the current TCP/IP configuration of the machine, similar to ipconfig for Windows systems.
Network ID
A number used in IP networks to identify the network on which a device or machine exists.
Host ID
The portion of an IP address that defines a specific machine in a subnet.
Routing Table
Actual instructions that tell the router what to do with incoming packets and where to send them.
00000000
0
11111111
255
ARP
Address Resolution Protocol
IANA
Internet Assigned Numbers Authority - formed to track and disperse IP addresses.
Jon Postel
Initially handled IANA.
Class Licenses
IANA passes out IP addresses in contiguous chunks.
Class A
First Decimal Value: 1-26; Addresses: 1.0.0.0-126.255.255.2555; Hosts/Network ID: 16,277,244
Class B
First Decimal Value: 128-191; Addresses: 128.0.0.0.-191.255.255.255; Hosts/Network ID: 65,534
Class C
First Decimal Value: 192-223; Addresses: 192.0.0.0-223.255.255.255; Hosts/Network ID: 254
Class D
First Decimal Value: 1-26; Addresses: 1.0.0.0-224.0.0.0-239.255.255.255; Hosts/Network ID: Multicast
Class E
First Decimal Value: 1-26; Addresses: 240.0.0.0-254.255.255.255; Hosts/Network ID: Experimental
Broadcast
Every computer on the LAN hears the message
Unicast
Ehere one computer sends a message directly to another user
Multicast
A single computer sends a packet to a group of interested computers. Often used when routers talk to each other.
2^X-2=
X Represents the number of zeroes in the subnet mask.
DSM
Default Subnet Mask
NE
Network ID Extension
H
Hosts
Convert /25 into dotted decimal.
First write out 25 ones followed by 7 zeroes. Subnet masks are always 32 binary digits long. 11111111.11111111.11111111.10000000
Then convert to dotted decimal. 255.255.255.128
OSPF
Open Shortest Path First - An interior gateway routing protocol developed for IP networks based on the shortest path first or link-state algorithm.
