Module 14 - Networking Flashcards
What is a LAN?
Local Area Network: A computer network that covers only a small area, usually within one building.
What is a WLAN?
Wireless Local Area Network: A Type of LAN that does not use wires or cables to create connections, but instead transmits data over radio or infrared waves.
What is a WAN?
Wide Area Network: A network or group of networks that span a large geographical area.
What is a MAN?
Metropolitan Area Network: A network that covers a large campus or city. A small MAN is sometimes called a Campus Area Network (CAN).
What is a PAN?
A Personal Area Network: A Network centered around one individual, consisting of personal devices at close range typically within a few meters.
- Wireless PAN uses technologies such as Bluetooth and Infrared (IrDA)
What is a SOHO?
Small Office / Home Office: Refers to a small business or business-at-home.
What is a WAP?
Wireless Access Point: A device that allows wireless communication devices to connect to a wireless network using Wi-Fi, bluetooth, or related.
- WAP usually connets to a router and can relay data between the wireless devices and wired devices on the network.
What is a VPN?
Virtual Private Network: Uses a public network, such as the internet, to carry encrypted traffic between two points, such as between two remote offices.
- VPN is typically used to provide remote offices or individual users with secure access to their organization’s network.
- VPN can be contrasted wtih an expensive system of owned or leased lines.
- VPN provides the same capabilities at a much lower cost.
What is a NIC?
- Network Interface Card
- Connects the networking device to the media
- Converts signal used on the media to the type used by the networking device and vice-versa.
What is the difference between link lights and activity lights?
- Link light remains steady to indicate connectivity.
- Activity light blinks to indicate activity (network traffic passing through the NIC)
What is a MAC?
Media Access Control (MAC) Address:
- Unique address burned-in to the card by the manufacturer, sometimes called the hardware address or physical address.
- Address is 48 bits long, or 6 pairs of Hex digits.
What do the first three Hex pairs of a MAC Address represent?
The vendor
- The last three hex pairs represent the ID for the card itself.
What is an uplink port?
The connection between switches, when switches are combined to make a larger network.
How can you find the MAC address?
Revealed with the command ipconfig/all
What is a Repeater?
- Allow a cabling system to extend beyond its maximum allowed length by amplifying the network voltages so signals travel farther.
What is a Hub?
- A Data Concentrator
- A broadcast-based device (1 to many), when one host transmits, all hosts connected recieve.
- Inefficient and allow many collisions on the network.
- Link lights i ndicate connectivity and activity lights indicate traffic passing through.
- All activity lights light up whenever a host starts to transmit.
What is a Switch?
- A Data concentrator like a hub
- Unlike hub, it is unicast-based (1 to 1).
- One host transmits, only the destination host receives.
- Eliminates ethernet collisions
- Provides full duplexing, meaning two hosts can send and receive at the same time.
- A switch will light the 2 LED’s for the ports of two communicating hosts.
What type of port does a hub and switch both have?
Several RJ45 ports, typically in multiples of 4.
What is a proxy server?
- Sits between an organizations’s LAN and the internet
- “listens” for internet traffic, caches what is idnetified so that other requests to the same place could come from cache, thus speeding things up.
- Can also block traffic to the internet to to specific sites.
- Can provide caching, filtering, and monitoring of network traffic.
What is a Router?
A device that connects two different networks.
- Connects the LAN to the internet or to other internal/external networks
- Has at least 2 ports, one on the LAN side and one on the network side (often called WAN side)
What is a Gateway?
- A router that interconnects two netwroks that use two different network protocols.
- Could connect a TCP/IP to a IPX/SPX.
- A gateway can translate between hots on two networks.
What are routing protocols?
- Specifies how routers communicate with one another
- Can use several Network transmission methods on a single device to communicate with other routers.
T/F - Many routers allow you to connect to a configuration page via a browser and an IP address
True
What is a firewall?
A device and/or software that analyzes incoming/outgoing data packets and makes an allow or deny decision.
- Can look into the data packet and make decisions based on:
- Port number (80 = http, 25 = SMTP, etc)
- Source or destination IP address
- Type of protocol (TCP, UDP, etc)
What is NAS?
Network Attached Storage
- Device used to store data on a network
- Convenient method of sharing files among multiple computers on a network
- Benefits over file serves include faster data access and easier configuration.
What is VOIP?
Voice Over Internet Protocol
- Allows voice to be sent over data lines
- Benefits from Quality of Service (QoS), which assigns higher priorities to voice traffic.
- Phones use an RJ-45 connection
- Power over Ethernet (PoE) is used to provide power to VoIP phones
What is the DMZ?
Demilitarized Zone
- Provides a buffer zone that separates an internal network from the internet
- Firewalls separate internet from DMZ, and the DMZ from the internal network
- Types of serves typically placed in DMZ’s include:
- web servers
- front-end email servers
- gaming servers
What is the max cable length for 802.3 ethernet?
- 33 feet (10 meters)
- 100 feet (30 meters)
- 328 feet (100 meters)
- 1200 feet (366 meters)
- 328 feet (100 meters)
What is Peer-to-Peer networking model?
- Computers act as both clients and servers
- Difficult to administer - highly decentralized
- Works with 10 or less computers
- Called a Workgroup in Windows
What is the Client-Server Networking Model?
- Centralized server functions as repository for files and resources.
- Easy to administer
- Works well in large networks (10 + computers)
What is a Domain Controller?
- In Windows Domain network, a Domain Controller is a server used to store domain useraccounts that users can login with.
What are cached credentials?
- When a users logs into a domain, the user’s computer caches locally the domain account information.
- This allows the user to log into the domain even if they can’t connect to the Domain Controller server.
Which of the following will allow a user account to logon to Windows Vista when a Windows domain name needs to be specified (Select TWO):
- domain\username
- username@domain
- username-domain
- domain-username
- domain username
- domain\username
- username@domain
What does physical topology refer to?
The layout of cable that connects computers and other devices together.
What does Logical Topology refer to?
How data moves among network hosts.
What is Bus Topology?
- All nodes connect on a single coaxial cable
- Each end of network must be terminated
- Faulty terminators, connectors, or cables can disable part or whole network
What is Star Topology?
- All nodes connect to a central point, typically a hub or switch
- Uses different cable types, including twisted pair, fiber optic, wireless
- Failure of cable affects just one node
- Failure of concentrator (hub or switch) downs the network
What is Ring Topology?
- Ring of cable, one end connected to another
- Signals travel around the ring
- Token Ring and Fiber Distributed Data Interface (FDDI) are two popular examples
- Typical speed is either 4 or 16 Mbps
- Concentrator is called a Multi-Station Access Unit (MAU)
What is Mesh Topology?
- Every node is connected to every other mode
- Advantage is redundancy, disadvantage is cost
- Not practical for LANs
- Primarily used in WAN’s
Name Three Media Access Methods:
- Carrier Sense Multiple Access with Collision Detection (CSMA/CD)
- Carrier Sense Multiple Access with Collision Avoidance (CSMA/CA)
- Token Passing
Describe CSMA/CD:
- Carrier Sense Multiple Access with Collision Detection (CSMA/CD)
- Computer first listens to the wire.
- If no traffic detected, computer transmits its data
- If another computer transmits at the same time, a collision occurs and no data can be transmitted for either machine.
- Part of the IEEE 802.3 standard
Describe CSMA/CA:
Computer Sense Multiple Access with Collision Avoidance (CSMA/CA):
- Computer first listens to wire, if no traffic detected the computer sends a signal that it is rady to transmit data.
- If the ready signal transmits without a problem, computer than transmits its data.
- Used in IEEE 802.11 wireless networks and in AppleTalk
- Slower and less popular than CSMA/CD
Describe Token Passing:
- Special packet of data, called a token is passed from co mputer to computer.
- Any computer that has data to transmit must wait for the token
- Part of IEEE 802.5 standard, also known as Token Ring network
What is Full Duplex?
Can carry data in both directions at the same time
What is half duplex?
Can carry data in both directions, but only one direction at a time.
- Network hubs can run in this mode by design.
List 5 Different Connectors for Coaxial Cable:
- RG-8 (known as Thicknet 10base5) 15-pin AUT Attachment Unit Interface
- RG-58 (known as Thinnet 10base2) or BNC T - British Naval Connector
- RG-6 - used to carry audio/visual signals from devices such as cable boxes and satellite dishes to television displays. Used mainly with digital cable and satellite signals
- RG-59 - used mainly for analog cable TV
- F Connectors - typical coax connector seen in homes
Describe elements of Coaxial Cable:
- Single copper wire down the middle
- Braided shield around it
- Cable is stiff and difficult to work with
- Becoming increasingly rare in networks these days
What are the two types of Twisted Pair Cable:
- UTP - Unshielded Twisted Pair - Least expensive and most popular for Local Area Networks
- STP - Shielded Twisted Pair - metallic foil shielding around the pairs of wires protects from electromagnetic interference caused by electrical motors, transmitters, et. STP is more expensive, so it’s only used when situation demands.
What connectors are used in Twisted Pair Cables?
- RJ45 - for networking
- RJ11 - for telephones and dial-up modems
How many wires in UTP/STP cables?
Eight wires (four twisted pairs).
How many wires in Plain Old Telephone Service (POTS)?
Four wires - POTS uses RJ11 connectors
What are the wires twisted in UTP/STP?
Reduces crosstalk and resistance to outside interference.
What are the seven grades of UTP Cable?
- Cat 1 - Voice grade (VG), not for data
- Cat 2 - VG and low speed data
- Cat 3 - VG, 10 Mbps Ethernet, 4 Mbps Token Ring (most often found in POTS)
- Cat 4 - 16 Mbps Token Ring
- Cat 5 - 100 Mbps Ethernet (aka Fast Ethernet)
- Cat 5e - 1000 Mbps Ethernet
- Cat 6 - 1000 Mbps or higher Ethernet (thicker cable)
What is straight-through UTP cable used for?
- Used to connect two dissimilar devices to one another, such as a computer to a switch.
What is crossover UTP cable used for?
- Used to connect two similar devices to one another, such as computer direct to computer.
What are plenum rated cables?
- cables that do not give off toxic fumes when burned.
- Used inside plenums (spaces between floors of buildings)
- More expensive then PVC (polyvinyl chloride), but safer in the event of a fire
List five elements of Fiber Optic Cable:
- Signals transmitted as pulses of light through glass or plastic
- Immune to EMI (electromagnetic interference)
- Signals can travel much farther than on copper
- More expensive than copper
- Needs special tools, is fragile and more difficult to work with.
What is singlemode fiber?
- One frequency, light source is a laser
- Used for long hauls, up to 24 miles/40km
- More expensive than multimode
- More fragile than multimode, cannot be bent as much as multimode
What is multimode Fiber?
- Multi wavelengths, light source is LED
- Travels shorter distances than singlemode (up to 3000 feet)
- Cheaper and less fragile than singlemode
List Four Types of Fiber Optic Connectors:
- SC (Standard Connector)
- ST (Straight Tip)
- LC (Local Connector)
- MT-RJ (Mechanical transfer RJ)
What is the transfer speed and max length of ThinNet Cable (10Base2)?
- 10 Mbps
- 185 meters
- Uses BNC connector