9/8 Class

Question 1

TCP and UDP

Answer 1

operate at Transport Layer of OSI Model
TCP: connection oriented(session is established)
guaranteed delivery
UDP: not guaranteed

Question 2

TCP

Answer 2

three way handshake using a "flag field" set in the header
data transmitted in segments
SYN
SYN - ACK
ACK

Question 3

TCP

Answer 3

the systems agree upon a TCP sliding window and “segment” byte size
after segments are sent error checking occurs

Question 4

UDP

Answer 4

data transmitted in “datagrams”

not guaranteed, considered unreliable

Question 5

IANA

Answer 5

assigns ports
well known ports 10-1023
registered ports 1024-49151
dynamic ports 49152-65535

Question 6

ARP(address resolution protocol)

Answer 6

command shows contents of ARP
cache expires in predefined minutes
caches can be manually expired for troubleshooting

Question 7

HTTP

Answer 7

plain text runs on TCP port 80

Question 8

HTTPS

Answer 8

cipher text(encrypted) runs on TCP port 443

Question 9

FTP

Answer 9

runs on TCP port 21(sometimes port 20 for data transfer)
used command line or via GUI
may or may not require a password
all communication is in plain text (unencrypted)
unless SFTP or FTPS are used

Question 10

TFTP

Answer 10

runs on UDP port 69
does not require a password
all communication is in plain text(unencrypted)
most often used for system administration, such as booting routers or firmware updates, in a controlled environment

Question 11

telnet

Answer 11

runs on TCP port 23
command line remote operation of system
usually unix or linux, but can be used in windows
unencrypted, thus rarely used, instead SSH(secure shell) is more commonly used

Question 12

RDP Remote Desktop Services

Answer 12

runs on TCP port 3389
GUI equivalent of telnet
show the OS desktop in a window

Question 13

encryption sockets layer (SSL)

Answer 13

secures web sites (via HTTPS) and VPNs
provides encryption for confidentiality integrity and authentication
being replaced by TLS
runs on any TCP port (usually 443 for HTTPS)
Public Key Infrastructure (PKI) is required to manage Digital Certificates that are at the foundation of SSL
transport layer security (TLS) will replace SSL

Question 14

Secure Shell (SSH)

Answer 14

enables encrypted communications
often used in place of Telnet
does not require PKI instead using share keys
can tunnel other protocols
often used for cloud based communications

Question 15

internet protocol security IPSec

Answer 15

authentication is accomplished with the AH authentication Header
encryption is accomplished with ESP(encapsulating security protocol)
can be challenging with firewalls
commonly used with VPNs

Question 16

mail protocols

Answer 16

by default unencrypted but can utilize TLS
SMTP
server moves mail to another server
POP3
server moves mail to a client
IMAP
server moves a copy of mail to a client

Question 17

Lightweight Directory Access Protocol (LDAP)

Answer 17

runs on TCP 389
used for communication with directory services, such as Microsoft’s active directory
open vendor neutral protocol
by default unencrypted, but SLDAP(Secure LDAP) is available and run on port…..

Question 18

Kerberos

Answer 18

open, vendor neutral runs on TCP port 88
auth is proving an identity
fundamental to using microsofts active directory for domain level authentication
complex protocol, using time stamped tickets to continually authenticate users to resources

Question 19

PPTP(point to point tunneling protocol)

L2TP(Layer 2 tunneling protocol)

Answer 19

PPTP(point to point tunneling protocol) runs on TCP port 1723 to securely encrypt network traffic
primarily used on microsoft based networks
L2TP(Layer 2 tunneling protocol) runs on UDP

Question 20

Simple Network Management Protocol (SNMP)

Answer 20

runs on UDP port 161
used to manage network devices
not encrypted, should be use in….

Question 21

Internet Group Multicast protocol (IGMP)

Answer 21

is used for multicasting

works with IP directly(OSI Network Layer)

Question 22

Internet Control Message Protocol (ICMP)

Answer 22

is a core protocol…