Networking, 14th Edition by FitzGerald, Dennis,
Durcikova
EUI-48 addresses - What are they? How big are they? What do they look like? What
are they used for? - ANSWER:EUI-48 is the link-layer address of ethernet devices.
They are 48 bits or 6 bytes long. Example 00 21 2F B5 6E 10. Used to identify the
data link address?
IP addresses - What are they? How big are they? What do they look like? What are
they used for? How do we get them? What is the difference between IPv4 and IPv6?
- ANSWER:IP addresses are a unique string of characters that identifies a computer
using the Internet Protocol. IPv4 is 32 bits long and IPv6 is 128 bits. IPv4 looks like
127.171.17.13 and IPv6 looks like 2001:db8::8a2e:370:7334. IP addresses are used
for uniquely identifying computers using the Internet Protocol on a network so that
they may send and receive packets. IP addresses are assigned by the ISP. The
difference is mostly bit length and appearance, IPv4 is running out of addresses as
well where as IPv6 should be able to handle the exhaustion of IP addresses.
Private IP address - ANSWER:Private (internal) addresses are not routed on the
Internet, and no traffic can be sent to them from the Internet; they are only
supposed to work within the local network.
Dynamic Host Configuration Protocol (DHCP) - ANSWER:Allows dynamic IP address
allocation so users do not have to have a preconfigured IP address to use the
network
Domain Name System (DNS) - ANSWER:Internet service that translates domain
names into IP addresses.
What are the three types of DNS server? - ANSWER:1. DNS stub resolver server (A
stub resolver is a software component normally found in endpoint hosts that
generates DNS queries when application programs running on desktop computers or
mobile devices need to resolve DNS domain names.)
2. DNS recursive resolver server (the resolver will perform as many queries as
necessary to obtain the response to the original query and then send the response
back to the stub resolver.)
3. DNS authoritative server (Authoritative nameservers are like the phone book
company that publishes multiple phone books, one per region.)
What is TTL? What is it used for? - ANSWER:Time to Live: The field added to a packet
and given a value by a source host, usually between 64 and 128. Each router along
the way decrements the TTL field by one. A router decrementing the TTL to zero will
discard the packet; this prevents misaddressed packets from circulating endlessly
among packet switches in search of their nonexistent destinations.
, Where can you find the TTL value? - ANSWER:using the dig on the terminal or
command line.
What is ARP? - ANSWER:Address Resolution Protocol - resolves IPV4 address to MAC
addresses
What does a router do? - ANSWER:Connects computers and transmits data to
correct destination on network. Forward ("route)" data using fastest available path
What does a switch do? - ANSWER:A network switch forwards data packets between
devices. Switches send packets directly to devices, rather than sending them to
networks like a router does.
What is the difference between a router and a switch? - ANSWER:Router works at
network layer and is responsible to find the shortest path for a packet whereas
Switch connects various devices in a network. (physical layer)
What is the TCP/IP protocol? - ANSWER:TCP/IP stands for Transmission Control
Protocol/Internet Protocol. TCP/IP is a set of standardized rules that allow
computers to communicate on a network such as the internet.
What devices use TCP/IP? - ANSWER:Web applications (layer 5), routers (layer 3),
switches and computers (layer 2), cables (layer 1)
What are the five layers of TCP/IP? - ANSWER:Layer 1 Physical
Layer 2 Data Link
Layer 3 Network
Layer 4 Transport
Layer 5 Application
What is the purpose of each layer? - ANSWER:Layer 1 Physical: The transceiver that
drives the signals on the network.
Layer 2 Data Link: responsible for creating the frames that move across the network.
Layer 3 Network: responsible for creating the packets that move across the network.
Layer 4 Transport: Establishes the connection between applications on different
hosts.
Layer 5 Application: The group of applications requiring network communications.
What are the standards for each layer? - ANSWER:Layer 1 Physical: 10 Base T,
802.11, Cat
Layer 2 Data Link: Ethernet, Wi-Fi
Layer 3 Network: IP
Layer 4 Transport: TCP/UDP
Layer 5 Application: HTTP, SMTP, etc.