Exam Essentials Chap 11 & 12 Flashcards
What makes up the fours layers of the TCP/IP model?
Application, Transport(Host-to-Host), Internet(Internetworking), and Link(Network Interface or Network Access)
How can TCP/IP be secured?
It can be secured using VPN links between systems. VPN links are encrypted to add privacy, confidentiality, and authentication and to maintain data integrity. You can also use TCP Wrappers.
What are the protocols used to establish VPNs?
Point-to-Point Tunneling Protocol (PPTP), Layer 2 Tunneling Protocol (L2TP), and Internet Protocol Security (IPsec).
What is the difference between TCP and UDP?
TCP
- Supports Full-duplex communications
- Connection oriented
- Uses a handshake process(SYN, SYN/ACK, ACK)
UDP
- Simplex connectionless protocol
- Connectionless ‘best effort’
- Low overhead
What is Telnet? What port does it operate at?
This is a terminal emulation network application that supports remote connectivity for executing commands and running applications but does not support transfer of files. TCP Port 23
What is the File Transfer Protocol(FTP)? What port does it operate at?
This is a network application that
supports an exchange of files that requires anonymous or specific authentication. TCP Ports 20 and 21
What is the Trivial File Transfer Protocol(TFTP)? What port does it operate at?
This is a network application that
supports an exchange of files that does not require authentication. UDP Port 69
What is the Simple Mail Transfer Protocol(SMTP)? What port does it operate at?
This is a protocol used to transmit
email messages from a client to an email server and from one email server to another. TCP Port 25
What is the Post Office Protocol(POP3)? What port does it operate at?
This is a protocol used to pull email messages
from an inbox on an email server down to an email client. TCP Port 110
What is the Internet Message Access Protocol(IMAP)? What port does it operate at?
This is a protocol used to pull email messages from an inbox on an email server down to an email client. IMAP is more secure than POP3 and offers the ability to pull headers down from the email server as well as to delete messages directly off the email server without having to download to the local client first. TCP Port 143
What is the Dynamic Host Configuration Protocol(DHCP)? What port does it operate at?
DHCP uses port
67 for server point-to-point response and port 68 for client request broadcasts. It is used to
assign TCP/IP configuration settings to systems upon bootup. DHCP enables centralized
control of network addressing. UDP Ports 67 and 68
What is the Hypertext Transport Protocol(HTTP)? What port does it operate at?
This is the protocol used to transmit
web page elements from a web server to web browsers. TCP Port 80
What is the Secure Sockets Layer(SSL)? What port does it operate at?
This is a VPN-like
security protocol that operates at the Transport layer. SSL was originally designed to support
secured web communications (HTTPS) but is capable of securing any Application
layer protocol communications. TCP Port 443 (for HTTP Encryption)
What is Line Print Daemon(LPD)? What port does it operate at?
This is a network service that is used to spool
print jobs and to send print jobs to printers. TCP Port 515
What is X Window? What port does it operate at?
This is a GUI API for command-line operating
systems. TCP Ports 6000–6063
What is the Bootstrap Protocol(BootP)? What port does it operate at?
This is a protocol used to connect diskless workstations to a network through auto assignment of IP configuration and download of basic OS elements. BootP is the forerunner to Dynamic Host Configuration Protocol (DHCP). UDP Ports
67 and 68
What is Network File System(NFS)? What port does it operate at?
This is a network service used to support file
sharing between dissimilar systems. TCP Port 2049
What is the Simple Network Management Protocol(SNMP)? What port does it operate at?
This is a network service used to collect network health and status information
by polling monitoring devices from a central monitoring station. UDP Port 161 (UDP Port 162 for Trap
Messages)
What are some benefits of Multilayer protocols? What are some drawbacks?
Benefits
-A wide range of protocols can be used at higher layers.
-Encryption can be incorporated at various layers.
-Flexibility and resiliency in complex network structures is supported.
Drawbacks
-Covert channels are allowed.
-Filters can be bypassed.
-Logically imposed network segment boundaries can be overstepped.
What is Distributed Network Protocol(DNP3)?
It is used to support communications between data
acquisition systems and the system control equipment. This includes substation computers,
RTUs (remote terminal units) (devices controlled by an embedded microprocessor),
IEDs (Intelligent Electronic Devices), and SCADA master stations (i.e., control centers). DNP3 is an open and public standard. DNP3 is a multilayer protocol that functions similarly
to that of TCP/IP, in that it has link, transport, and transportation layers.
What are some vulnerabilities of TCP/IP?
Improperly implemented TCP/IP stacks in various operating systems are vulnerable to buffer overflows, SYN flood attacks, various DoS attacks, fragment attacks, oversized packet attacks, spoofing attacks, man-in-the-middle attacks, hijack attacks, and coding error attacks. TCP/IP (as well as most protocols) is also subject to passive attacks via monitoring or sniffing.
What are the three layers from top to bottom of addressing and naming when in use with TCP/IP networks?
Domain name, IP address, & MAC address
What are the characteristics of 10Base2(Thinnet)?
Max Speed: 10 Mbps Distance: 185 meters Difficulty of Installation: Medium Susceptibility to EMI: Medium Cost: Medium
What are the characteristics of 10Base5(Thicknet)?
Max Speed: 10 Mbps Distance: 500 meters Difficulty of Installation: High Susceptibility to EMI: Low Cost: High