Networking Services - Week 4, Basic networking protocols
What port on a name server is used for User Datagram Protocol (UDP) name request packets?
53 DNS uses port 53 over UDP for name resolution communications.
Switch
A computer networking device that connects network segments allowing devices to communicate with each other
IP address
A number that uniquely identifies each computer or device connected to the Internet.
Network (Protocols and Standards)
ARP, ICMP, IGMP, IP, IPSec, RARP
Presentation Layer (Duties)
Allows hosts and applications to use a common language; performs data formatting, encryption, and compression.
The Dynamic Configuration Host Protocol (DHCP) operates at which Open Systems Interconnection (OSI) model layer?
Application The application layer is used for communication protocols and methods in a network.
Layer 7
Application Layer #
Application (Protocols and Standards)
BOOTP, DHCP, DNS, FTP, HTTP, HTTPS, IMAP4,PING, POP3, NSLOOKUP, NTP, SFTP, SMTP, SNMP, Telnet, TFTP
At the very lowest level, what data does a computer understand?
Binary Numbers
A DNS record that's used to redirect traffic from one domain name to another is known as a _______ record.
CNAME A CNAME redirects a DNS resolution attempt from one domain name to another.
Which of the following allows computers on a network to automatically receive address assignment information?
DHCP
Layer 2
Data Link Layer #
DNS stands for _________.
Domain Name System
DNS
Domain Name System. Translates URLs to IP addresses.
DHCP
Dynamic Host Configuration Protocol. Used on IP networks automatically assigning IP addresses to devices
What benefits does the Domain Name System (DNS) provide?
Easy mapping to a new Internet Protocol (IP) address Ease of address memorisation
Transport Layer (Duties)
Ensures accurate delivery of data through flow control, segmentation and reassembly, error correction, and acknowledgement.
Network Layer (Duties)
Establishes network connections; translates network addresses into their physical counterparts and determines routing.
Session Layer (Duties)
Establishes, maintains, and terminates user connections.
The "www" portion of a domain is known by which of the given options?
Host Name Subdomain
HTTP
Hypertext Transfer Protocol - used to request and transfer hypertext data between clients and servers
HTTPS
Hypertext Transfer Protocol Secure. Secure communications among 2 computers ( one using browser and other fetching data from web server)
Administration and definition of TLDs are handled by a non-profit organization known as _______.
ICANN
Physical Link (Standards)
IEEE 802.3 (Ethernet), 802.5 (Token Ring), 802.11 (Wi-Fi)
A company moves a popular website to a new web host. Which of the following will change as a result?
IP address
Data Link (Protocols and Standards)
L2TP, PPP, PPTP, SLIP
Presentation (Protocols and Standards)
MIME, SSL, TLS
Physical Layer (Duties)
Manages signaling to and from physical network connections.
Layer 3
Network Layer #
A _______ record is responsible for resolving an IP to a domain name.
PTR PTR records operate as the inverse of an A Record.
Data Link Layer (Duties)
Packages data in frames appropriate to network transmission method.
Layer 1
Physical Layer #
Layer 6
Presentation Layer #
Application Layer (Duties)
Provides Interface between software applications and network for interpreting application requests and requirements. *Note: This layer is not the actual software application.
Session (Protocols and Standards)
RTP & SIP
When a client computer sends a request to a Domain Name System (DNS) server, what type of packet is sent?
SYN The requesting client initiates a query with a DNS server by sending a Synchronize (SYN) packet as a first step in the three-way handshake.
SMTP
Simple Mail Transfer Protocol. Send and distribute outgoing mail
SNMP
Simple Network Management Protocol. Used to collect information about managed devices on IP networks and modifying that info
A new Domain Name System (DNS) server is being configured. Which record type is used to declare a new zone?
State of Authority (SAO) An SOA record establishes a zone and maintains authority over the zone.
Transport (Protocols and Standards)
TCP & UDP
Routers
The "connection points" of the Internet. Networking devices that direct traffic between subnetworks on the Internet.
Layer 4
Transport Layer #
The Domain Name System (DNS) network service uses which transport layer protocol?
UDP DNS uses the UDP protocol for queries and resolution. It is a connectionless protocol.
cname
canonical name. provides for domain name aliases within zone
source host
host name for the primary dns server for the zone
mx
mail exchange. identifies email services within domain
ttl
minimum time to live for all records in the zone (Default is 3600 sec)
soa
start of authority. Identifies the primary name server for the zone. This record contains host name for the server responsible for all dns records within the name space and basic properties of the domain
retry time
the amount of time a secondary server will wait to retry if the zone transfer fails (Default is 600 sec)
TCP
transmission control protocol. Communicating over a network. Sent from a source to a destination connection oriented (slower)
a
address. maps an ip address to a host name and sued for dns lookup
refresh time
amount of time a secondary dns server will wait before asking for updates (Default is 3600 sec)
IANA has primarily been responsible with assigning address blocks to five regional internet registries (RIR). A tech needs to research address blocks assigned in the United States. Which RIR should the tech contact?
ARIN ARIN primarily serves the United States and Canada.
A video conferencing application isn't working due to a Domain Name System (DNS) port error. Which record requires modification to fix the issue?
Service Record (SRV)
Layer 5
Session Layer #
UDP
User Datagram Protocol. Used instead of TCP when guaranteed delivery of each packet is not necessary. Connectionless (faster)
contact email
email address of the person responsible for the zone file
expire time
max amount of time a secondary server will spend trying to complete a zone transfer (Default is 86,400 sec -1day-)
ns
name server. defines the name servers within your namespace
arin
network ranges
ptr
pointer. maps an ip address to a host name
netcraft
restricted urls and os information
An IT systems engineer creates a new Domain Name System (DNS) zone that contains pointer (PTR) resource records. Which zone type has been created?
reverse lookup
serial number
revision number of the zone file
srv
service. Defines the hostname and port number of services