Chapter 11- Secure Network Architecture and Securing Network Components Flashcards
- What is protocol
Protocol is a set of rules and restrictions that determine how data is transmitted over a network medium
- OSI Model divides networking into 7 distinct layers, name them:
Please do Not Throw Sausage Pizza Away
Application 7
Presentation 6
Session 5
Transport 4
Network 3
Data 2
Physical 1
- What is encapsulation
encapsulation occurs as data moves down through OSI Model Layers from Application to Physical. It is the addition of a header and possibly a footer to the data received by each layer from the layer above before it is handed to the layer below
- What is de-encapsulation
De-encapsulation occurs when data moves up through OSI model layers from Physical to Application
- What happens at the presentation layer during encapsulation
The presentation layer encapsulates the message by adding information to it, information is added at the beginning of the message i.e. a header.
- How do ISO Layers change data
D3SPFB
Application Data Stream
Presentation Data Stream
Session Data Stream
Transport Segment (TCP)/Datagram (UDP)
Network Packet
Data Frame (Link)
Physical Bits
- What is physical layer:
accepts frame from the data link layer and converts frame into bits for transmission over the physical connection medium. It also receives bits from the physical connection medium and converts them into frame to be used by the data link layer.
- Through device drivers and standards list the things that physical layer controls:
Throughput rates
It handles synchronisation
Manages line noise and medium access
Determines whether to use analogue or digital signals
- List network hardware devices that function at layer 1:
(NHRCA) Network Interface Cards (NICs), hubs, repeaters, concentrators and amplifiers.
- What is data layer
Data Layer is responsible for formatting the packet from the Network layer into the proper format for transmission. data link layer includes adding the hardware source and destination addresses to the frame. The hardware address is the Media Access Control Address (MAC)
- List protocols found in the data link layer:
SPALLPI
Serial Line Internet Protocol (SLIP)
Point to Point Protocol (PPP)
Address Resolution Protocol (ARP)
Layer 2 Forwarding (L2F)
Layer 2 Tunnelling Protocol (L2TP)
Point to Point Tunnelling Protocol (PPTP)
Integrated Services Digital Network (ISDN)
- What is ARP?
Address Resolution Protocol (ARP) is a protocol the datalink Layer. It can be viewed as operating in layer 2 or 3 of the OSI model. It depends on the ethernet’s source and destination MAC addresses. ARP is used to resolve IP addresses into MAC addresses.
- ARP is carried as a _____ of the ______:
Payload, the Ethernet Frame
- ARP operates in what layer?
Tricky question! some think it operates on Layer 2,anyway choose 2. Layer 2
Layer 3 – Network layer but it does not operate as a true layer 3 protocol as it does not use a source destination addressing scheme to direct communications. It depends on the Ethernet source and the destination MAC addresses.
- Hardware technology used in data layer
Ethernet (IEEE802.3), Token Ring (IEEE 802.5), Asynchronous Transfer Mode (ATM), Fibre Distributed Data Interface (FDDI), Copper Distributed Data Interface (CDDI)
- Data link layer contains 2 sublayers they are
Logical Link Control and Media Access Control (MAC) Sublayer
- List Network Hardware that function at layer 2
at datalink layer… switches and bridges
- Explain Network Layer
Network layer is responsible for adding routing and addressing information to data. Packet includes source and destination addresses. The Network layer is responsible for providing routing or delivery information, but it is not responsible for verifying guaranteed delivery
- List routing protocols under network layer:
BORI5NS
Internet Control Message Protocol (ICMP)
Routing Information Protocol (RIP)
Open Shortest Path First (OSPF)
Border Gateway Protocol (BGP)
Internet Group Management Protocol (IGMP)
Internet Protocol (IP)
Internet Protocol Security (IPSec)
Internetwork Packet Exchange (IPX)
Network Address Translation (NAT)
Simple Key Management for Internet Protocols (SKIP)
- What are routers
routers determine the best logical paths for the transmission of packets based on speed, hops, preference and so on.
routers use destination IP addresses to guide the transmission of packets.
- List some network hardware devices that function at layer 3:
Routers and bridge routers (brouters)
a
a
- What are brouters:
Bridge routers (brouters) works primarily in layer 3 but in layer 2 when necessary.
- What is the transport layer
. Transport layer is responsible for managing the integrity of a connection and controlling the session. A PDU Payload Data Unit from the session layer is converted into segment. This layer includes mechanisms for segmentation, sequencing, error checking, controlling the flow of data, error correction, multiplexing and network service optimisation.
- PDU acronym means
Payload Data Unit, Protocol Data Unit, Packet Data Unit.
- List Protocols that operate on the transport layer:
the following operate on the transport layer, Transport Control Protocol (TCP),
User Datagram Protocol (UDP),
Sequenced Packet Exchange (SPX),
Secure Socket Layer (SSL),
Transport Layer Security (TLS).
- What is PDU
means Payload Data Unit, Protocol Data Unit, Packet Data Unit. PDU is a container of information or data passed btw network layers.
- Explain Session Layer:
Session Layer (Layer 5) is responsible for establishing, maintaining and terminating communication sessions between 2 computers. It manages dialogue discipline or dialogue control (simplex, half duplex, full duplex).
- List Protocols that operate within the session Layer:
Network File System (NFS), Structured Query Language (SQL), Remote Procedure Call (RPC).
- Communication sessions can operate in one of three diff control modes in the session layer, list them:
Simplex- one way communication, half-duplex- 2 way communications; but only one direction can send data at a time, full-duplex- 2 way communication, in which data can be sent in both directions simultaneously.
- What is presentation layer
presentation layer is responsible for transforming data received from application layer into a format that any system following the OSI model can understand.
- Which layer is responsible for encryption and compression:
Presentation Layer (Layer 6).
- What is application layer:
it is responsible for interfacing user applications, network services, or operating system with protocol stack. The application is not located in this layer rather protocols and services required to transmit files, exchange messages, connect to remote terminals are found here
- Protocols found in the presentation layer are?
American Standard for Code Information Interchange (ASCII)
Extended Binary Coded Decimal Interchange Mode (EBCDICM)
Tagged Image File Format (TIFF)
Joint Photographic Experts Group (JPEG)
Moving Picture Experts Group (MPEG)
Musical Instrument Digital Interface (MIDI)
- Protocols found in the application layer are:
- Protocols found in the application layer are: Hypertext Transfer Protocol (HTTP)
File Transfer Protocol (FTP), Line Print Daemon (LPD), Simple Mail Transfer Protocol (SMTP), Telnet, Trivial File Transfer Protocol (TFTP),Electronic Data Interchange (EDI), Post Office Protocol version 3 (POP3),Internet Message Access Protocol (IMAP), Simple Network Management Protocol (SNMP), Network News Transport Protocol (NNTP), Secure Remote Procedure Call (S-RPC),Secure Electronic Transaction (SET
- Name the network device that works at the application layer:
Gateway.
- TCP/IP Acronym
Transmission Control Protocol/ Internet Protocol
- List the layers of TCP/IP:
Application, Transport, Internet and Link
- Compare the OSI model to TCP/IP Model
Application Application
Presentation Application
Session Application
Transport Transport
Network Internet
Data Link Link
Physical Link
- Compare the Application mode of the TCP/IP model to OSI:
Application Mode is also known as the process. The application mode of the TCP/IP Model is synonymous to the Application, Presentation and Session modes of the OSI.
- Compare the transport mode of the TCP/IP to OSI model:
The transport mode is also known as host to host and it is likened to the transport mode of the OSI model
- Compare the Network mode of the OSI model to TCP/IP:
this model is known as the internet or internetworking.
- Compare Data Link and Physical Mode of the OSI model to the TCP/IP Model:
the data link and physical layers of the OSI model are likened to the link model of the TCP/IP
- TCP/IP can be secured using……:
Virtual Private Networks
- Advantages of VPN:
VPN links are encrypted to add privacy, confidentiality and authentication.
- List Protocols used to establish VPNs:
Point to Point Tunneling Protocol (PPTP), Layer 2 Tunneling Protocol (L2TP), Secure Shell (SSH), Open VPN (SSL/TLS VPNs) and Internet Protocol Security (IPSec).
- List Protocol in Application state of TCP/IP:
: File Transfer Protocol FTP, Telnet, Simple Network Management Protocol SNMP, Line Print Daemon LPD, Trivial File Transfer Protocol TFTP, Simple Mail Transfer Protocol SMTP, NFS, X Window
- What are TCP wrappers?
TCP wrappers is an application that can serve as a basic firewall by restricting access to ports and resources based on user IDs or system IDs.
- List 2 TCP/IP Transport Layer Protocols:
Transmission Control Protocol (TCP) and User Datagram Protocol (UDP).
- Explain TCP (TCP/IP) Protocol:
Transmission Control Protocol (TCP) Internet Protocol is a full duplex connection oriented protocol. Operates at transport layer of the OSI model.
- Explain UDP (TCP/IP) Protocol:
User Datagram Protocol (UDP) is a simplex connectionless protocol. It operates at transport layer of the OSI model, it offers no error detection or correction, does not use sequencing, does not use flow control mechanism, does not use preestablished session and is considered unreliable.
- What is a port?
Port is a little more than an address number that both ends of the communication link agree to use when transferring data within the transport layer. Ports allow a single IP address to be able to support multiple simultaneous communications each using a different port no
- What is socket?
A combination of IP address and port number is known as socket
- Ports 0 -1023 are known as:
Well known ports or service ports
- Ports 1024 to 19151 are known as:
registered software ports
These are ports that have one or more networking software products specifically registered with International Assigned Numbers Authority (IANA).
- Ports 49152 to 65535 are known as
Random, Dynamic Ephemeral Ports as they are randomly and temporarily used by clients as a source port. The IANA recommends that ports 49152 to 65535 be used as dynamic and/or private ports.
- Explain the TCP three-way handshake:
1 the client sends a SYN (synchronise) flagged packet to the client. 2. The server responds with a SYN/ACK (synchronise and acknowledge) flagged packet back to the client. 3. The client responds with an ACK (acknowledge) flagged packet back to the server
- List TCP headers flag field:
Unskilled Attackers Pester Real Security Folk. CWR, ECE, URG, ACK, PSH,RST,SYN,FIN) i.e. Congestion Window Reduced, Explicit Congestion Notification-Echo, Urgent, Acknowledgement, Push, Reset, Synchronize, Finish.
- What is UDP used for:
UDP is often employed by real time or streaming communications for audio and video.
- Describe UDP Header
: UDP header is 8bytes (64 bits) long. The header is divided into 4 sections or fields (each 16 bits long). Source Port, Destination Port, message length and checksum.
- Describe TCP/IP Internet Protocol:
it operates at the Network Layer of the OSI model and is known as the Internet Protocol (IP). IP provides route address for data packets.it provides means of identity and prescribes transmission paths. It is similar to UDP, IP is connectionless and unreliable.
- Compare IPv4 to IPv6:
IPv4 IPV6
32bits addressing 128bits addressing
- List some IPv6 features that are not present in \IPv4:
Scoped Addresses, autoconfiguration and Quality of Service
- Describe advantage of IPv6 scoped addressing:
IPv6 scoped addresses give the administrators the ability to group and then block or allow access to network services such as file servers or printing.
- What is IPv6 autoconfiguration?
IPv6 Autoconfiguration removes the need for both Dynamic Host Configuration Protocol (DHCP) and Network Address Translation (NAT).
- List the layers of TCP/IP
Application, Transport, Internet and Link
- Compare the OSI model to TCP/IP Model
Application Application
Presentation Application
Session Application
Transport Transport
Network Internet
Data Link Link
Physical Link
- Compare the Application mode of the TCP/IP model to OSI:
Application Mode is also known as the process. The application mode of the TCP/IP Model is synonymous to the Application, Presentation and Session modes of the OSI.
- Compare the transport mode of the TCP/IP to OSI model:
The transport mode is also known as host to host and it is likened to the transport mode of the OSI model
- Compare the Network mode of the OSI model to TCP/IP:
: this model is known as the internet or internetworking.
- Compare Data Link and Physical Mode of the OSI model to the TCP/IP Model:
the data link and physical layers of the OSI model are likened to the link model of the TCP/IP.
- TCP/IP can be secured using……:
Virtual Private Networks
- Advantages of VPN:
VPN links are encrypted to add privacy, confidentiality and authentication.
- List Protocols used to establish VPNs:
Point to Point Tunneling Protocol (PPTP), Layer 2 Tunneling Protocol (L2TP), Secure Shell (SSH), Open VPN (SSL/TLS VPNs) and Internet Protocol Security (IPSec).
- List Protocol in Application state of TCP/IP
: File Transfer Protocol FTP, Telnet, Simple Network Management Protocol SNMP, Line Print Daemon LPD, Trivial File Transfer Protocol TFTP, Simple Mail Transfer Protocol SMTP, NFS, X Window
- What are TCP wrappers?
TCP wrappers is an application that can serve as a basic firewall by restricting access to ports and resources based on user IDs or system IDs.
- List 2 TCP/IP Transport Layer Protocols:
Transmission Control Protocol (TCP) and User Datagram Protocol (UDP).
- Explain TCP (TCP/IP) Protocol:
Transmission Control Protocol (TCP) Internet Protocol is a full duplex connection oriented protocol. Operates at transport layer of the OSI model
- Explain UDP (TCP/IP) Protocol:
User Datagram Protocol (UDP) is a simplex connectionless protocol. It operates at transport layer of the OSI model, it offers no error detection or correction, does not use sequencing, does not use flow control mechanism, does not use preestablished session and is considered unreliable
- What is a port?
Port is a little more than an address number that both ends of the communication link agree to use when transferring data within the transport layer. Ports allow a single IP address to be able to support multiple simultaneous communications each using a different port no.
- What is socket?
A combination of IP address and port number is known as socket
- Ports 0 -1023 are known as:
registered software ports
These are ports that have one or more networking software products specifically registered with International Assigned Numbers Authority (IANA).
- Ports 1024 to 19151 are known as: registered software ports
These are ports that have one or more networking software products specifically registered with International Assigned Numbers Authority (IANA).
- Ports 49152 to 65535 are known as
Random, Dynamic Ephemeral Ports as they are randomly and temporarily used by clients as a source port. The IANA recommends that ports 49152 to 65535 be used as dynamic and/or private ports.
- Explain the TCP three-way handshake
1 the client sends a SYN (synchronise) flagged packet to the client. 2. The server responds with a SYN/ACK (synchronise and acknowledge) flagged packet back to the client. 3. The client responds with an ACK (acknowledge) flagged packet back to the server
- List TCP headers flag field
Unskilled Attackers Pester Real Security Folk. CWR, ECE, URG, ACK, PSH,RST,SYN,FIN) i.e. Congestion Window Reduced, Explicit Congestion Notification-Echo, Urgent Acknowledgement, Push, Rest, Synchronize, Finish.
- What is UDP used for
UDP is often employed by real time or streaming communications for audio and video.
- Describe UDP Header
UDP header is 8bytes (64 bits) long. The header is divided into 4 sections or fields (each 16 bits long). Source Port, Destination Port, message length and checksum.
- Describe TCP/IP Internet Protocol
: it operates at the Network Layer of the OSI model and is known as the Internet Protocol (IP). IP provides route address for data packets.it provides means of identity and prescribes transmission paths. It is similar to UDP, IP is connectionless and unreliable.
- Compare IPv4 to IPv6:
IPv4 IPV6
32bits addressing 128bits addressing
- List some IPv6 features that are not present in IPv4:
Scoped Addresses, autoconfiguration and Quality of Service
- Describe advantage of IPv6 scoped addressing
IPv6 scoped addresses give the administrators the ability to group and then block or allow access to network services such as file servers or printing.
- What is IPv6 autoconfiguration?
IPv6 Autoconfiguration removes the need for both Dynamic Host Configuration Protocol (DHCP) and Network Address Translation (NAT).
66. What is IPv6 Quality of Service? IPv6 Quality of Service (QoS) priority values allow for traffic management based on prioritized content.
- What is IPv6 Quality of Service
IPv6 Quality of Service (QoS) priority values allow for traffic management based on prioritized content
- Describe Internet Control Message Protocol (ICMP):
Internet Control Message Protocol is used to determine the health of a network or a specific link
- ICMP Acronym means:
Internet Control Message Protocol
- Internet Control Message Protocol (ICMP) is utilised by:
Ping, traceroute, pathping and any other network management tools.
- Describe ping in Internet Control Message Protocol (ICMP):
ping utility employs ICMP echo packets and bounces them off remote systems. Ping can be used to check is a remote system is online.
- Internet Control Message Protocol (ICMP) are exploited by
Denial of Service (DoS), ping of death, smurf attacks and ping floods.
- Explain Ping of Death
Ping of Death sends a malfunctioned ping larger than 65,535 bytes to a computer in order to crash it.
Note: Malfunctioned ping is an IP packet that lacks order or contains a code that is expected to confuse or disrupt computers, firewalls, routers or any service present on a network.
- Explain Smurf Attacks
Smurf attacks generate enormous amounts of traffic on a target network by spoofing broadcast pings. It is a Distributed Denial of Service attack (DDoS)
Wiki: It is a distributed denial of service attack in which large numbers of internet control message protocol (ICMP) packets with the intended victim’s spoofed source IP are broadcast to a computer network using an IP broadcast address.
Spoofing involves creating of an IP packet with false IP address for the purpose of impersonating another computer system.
- Describe Internet Group Management Protocol
Internet Group Management Protocol (IGMP) allows systems to support multicasting. it is used by hosts to register their dynamic multicast group membership. Multicasting is the transmission of data to multiple specific recipients. It is also used by connected routers to discover these groups
- What is multicasting
multicasting is the transmission of data to multiple specific recipients.
- What is Address Resolution Protocol (ARP):
Address Resolution Protocol is essential to the interoperability of logical and physical addressing schemes. ARP uses caching and broadcasting to perform its operations. The basis of ARP is Media Access control.
ARP should:
Accept Request: A new device asks to join the LAN, providing and IP address
Translate: Devices on the LAN don’t communicate via IP address
Send Requests:
- Term for Address Resolution Protocol abuse is
Address Resolution Protocol cache (ARP) Poisoning.
- Define ARP cache poisoning:
ARP cache poisoning is where an attacker inserts bogus information into the ARP cache. It is also known as ARP Spoofing
- Describe Telnet
this is a terminal emulation network application that supports remote connectivity for executing commands and running applications but not support transfer of files.
- What is port for Telnet:
TCP Port 23
- Describe File Transfer Protocol (FTP
File Transfer Protocol: This is a network application that supports an exchange of files that requires anonymous or specific authentication
- Acronym for FTP means:
File Transfer Protocol
- File Transfer Protocol Port:
TCP Port 20 for passive data or active (ephemeral) data and data transfer and Port 21 for control connection
- Acronym for TFTP means:
Trivial File Transfer Protocol
- Describe Trivial File Transfer Protocol (TFTP):
Trivial File Transfer Protocol is a network application that supports the exchange of files that does not require authentication
- Trivial File Transfer Protocol (TFTP) Port
UDP Port 69
- Describe Simple Mail Transfer Protocol (SMTP)
this is a protocol used to transmit email messages from a client to an email server and from one email server to another.
88. SMTP acronym means- Simple Mail Transfer Protocol
- SMTP acronym means
Simple Mail Transfer Protocol
- SMTP_ Simple Mail Transfer Protocol operates from which port
TCP Port 25
- ICMP and IGMP operate in which layer of the OSI model?
Network Layer- Layer 3.
- POP3 Means
Post Office Protocol
- POP3 Port- TCP Port 110
- Describe POP3:
This is a protocol used to pull email messages from inbox on an email server down to an email client. TCP Port 110
- IMAP Means
Internet Message Access Protocol
POP3 Port
TCP Port 110
- IMAP (Internet Message Access Protocol) Port-
TCP Port 143