network fundamentals module 3
Protocols must account for the following requirements to successfully deliver a message that is understood by the receiver:
An identified sender and receiver Common language and grammar Speed and timing of delivery Confirmation or acknowledgment requirements
TCP/IP Model Layer Internet
Determines the best path through the network.
internet engineering task force (IETF)
Develops, updates, and maintains Internet and TCP/IP technologies. This includes the process and documents for developing new protocols and updating existing protocols know as Request for Comments (RFC) documents.
DNS
Domain Name System. Translates domain names such as cisco.com, into IP addresses.
TCP/IP Model Layer Network Access
Controls the hardware devices and media that make up the network.
ARP
Address Resolution Protocol. Provides dynamic address mapping between an IPv4 address and a hardware address.
True or false. Standards organizations are usually vendor-neutral.
true
Which protocol operates at the network access layer of the TCP/IP model?
Ethernet
File Transfer
FTP,SFTP,TFTP
Web and Web Service
HTTP,HTTPS,REST
These are the benefits of using a layered model to describe network protocols and operations:
Assisting in protocol design because protocols that operate at a specific layer have defined information that they act upon and a defined interface to the layers above and below Fostering competition because products from different vendors can work together Preventing technology or capability changes in one layer from affecting other layers above and below Providing a common language to describe networking functions and capabilities
Host Config
DHCPv4, DHCPv6,SLAAC
Which two protocols are service discovery protocols?
DNS, DHCP
Which two protocols belong in the TCP/IP model application layer?
DNS, DHCP
FTP
File Transfer Protocol. Sets the rules that enable a user on one host to access and transfer files to and from another host over a network. FTP is a reliable, connection-oriented, and acknowledged file delivery protocol.
HTTPS
HTTP Secure. A secure form of HTTP that encrypts the data that is exchanged over the World Wide Web
A device receives a data link frame with data and processes and removes the Ethernet information. What information would be the next to be processed by the receiving device?
IP at the internet layer
Response Timeout
If a person asks a question and does not hear a response within an acceptable amount of time, the person assumes that no answer is coming and reacts accordingly. The person may repeat the question or instead, may go on with the conversation. Hosts on the network use network protocols that specify how long to wait for responses and what action to take if a response timeout occurs.
OSPF
Open Shortest Path First. Link-state routing protocol that uses a hierarchical design based on areas. OSPF is an open standard interior routing protocol.
there are two layered models that are used to describe network operations:
Open System Interconnection (OSI) Reference Model TCP/IP Reference Model
Institute of Electrical and Electronics Engineers (IEEE
Organization of electrical engineering and electronics dedicated to advancing technological innovation and creating standards in a wide area of industries including power and energy, healthcare, telecommunications, and networking. Important IEEE networking standards include 802.3 Ethernet and 802.11 WLAN standard. Search the internet for other IEEE network standards.
Telecommunications Industry Association (TIA)
Organization responsible for developing communication standards in a variety of areas including radio equipment, cellular towers, Voice over IP (VoIP) devices, satellite communications, and more.
Service Discovery Protocols
Protocols are used for the automatic detection of devices or services. Examples of service discovery protocols include Dynamic Host Configuration Protocol (DHCP) which discovers services for IP address allocation, and Domain Name System (DNS) which is used to perform name-to-IP address translation.
Routing Protocols
Protocols enable routers to exchange route information, compare path information, and then to select the best path to the destination network. Examples of routing protocols include Open Shortest Path First (OSPF) and Border Gateway Protocol (BGP).
Network Security Protocols
Protocols secure data to provide authentication, data integrity, and data encryption. Examples of secure protocols include Secure Shell (SSH), Secure Sockets Layer (SSL), and Transport Layer Security (TLS).
this protocols is responsible for guaranteeing the reliable delivery of information
TCP
Message Destination (receiver)
The destination receives the message and interprets it.
Access method
This determines when someone can send a message. Click Play in the figure to see an animation of two people talking at the same time, then a "collision of information" occurs, and it is necessary for the two to back off and start again. Likewise, when a device wants to transmit on a wireless LAN, it is necessary for the WLAN network interface card (NIC) to determine whether the wireless medium is available.
Flow control
This function ensures that data flows at an efficient rate between two communicating devices. TCP provides flow control services.
Error Detection
This function is used to determine if data became corrupted during transmission. Various protocols that provide error detection include Ethernet, IPv4, IPv6, and TCP.
Reliability
This function provides guaranteed delivery mechanisms in case messages are lost or corrupted in transit. TCP provides guaranteed delivery.
Flow Control
This is the process of managing the rate of data transmission. Flow control defines how much information can be sent and the speed at which it can be delivered. For example, if one person speaks too quickly, it may be difficult for the receiver to hear and understand the message. In network communication, there are network protocols used by the source and destination devices to negotiate and manage the flow of information.
TFTP
Trivial File Transfer Protocol. A simple, connectionless file transfer protocol with best-effort, unacknowledged file delivery. It uses less overhead than FTP.
Note:
You may see other documentation state that ARP operates at the Internet Layer (OSI Layer 3). However, in this course we state that ARP operates at the Network Access layer (OSI Layer 2) because it's primary purpose is the discover the MAC address of the destination. A MAC address is a Layer 2 address.
internet corporation for assigned names and numbers (ICANN)
based in the united states, ICANN coordinates IP address allocation the management of domain names and assignment of other information used in TCP/IP protocols
internet protocol suite or TCP/IP
this is the most common and relevant protocol suite used today. the TCP/IP protocol suite is an open standard protocol suite maintained by the internet engineering task force (IETF)
standards based protocol suite
this means it has been endorsed b the networking industry and approved by a standards organization. this ensures that products from different manufacturers can interoperate successfully
open standard protocol suite
this means it is freely available to the public and can be used by any vendors on their hardware or in their software
Transmission Control Protocol (TCP)
this protocol manages the individual conversations. TCP is responsible for guaranteeing the reliable delivery of the information and managing flow control between the end devices.
UDP and TCP belong to which layer of the TCP/IP protocol?
transport
NAT
Network Address Translation. Translates IPv4 addresses from a private network into globally unique public IPv4 addresses.
An IP address contains two parts:
Network portion (IPv4) or Prefix (IPv6),Host portion (IPv4) or Interface ID (IPv6)
DHCPv4
Dynamic Host Configuration Protocol for IPv4. A DHCPv4 server dynamically assigns IPv4 addressing information to DHCPv4 clients at start-up and allows the addresses to be re-used when no longer needed.
DHCPv6
Dynamic Host Configuration Protocol for IPv6. DHCPv6 is similar to DHCPv4. A DHCPv6 server dynamically assigns IPv6 addressing information to DHCPv6 clients at start-up.
EIGRP
EIGRP - Enhanced Interior Gateway Routing Protocol. An open standard routing protocol developed by Cisco that uses a composite metric based on bandwidth, delay, load and reliability.
Message timing includes the following:
Flow Control,Response Timeout,Access method
internet research task force (IRTF)
Focused on long-term research related to Internet and TCP/IP protocols such as Anti-Spam Research Group (ASRG), Crypto Forum Research Group (CFRG), and Peer-to-Peer Research Group (P2PRG).
HTTP
Hypertext Transfer Protocol. A set of rules for exchanging text, graphic images, sound, video, and other multimedia files on the World Wide Web.
Which three acronyms/initialisms represent standards organizations? (Choose three.)
IANA, IEEE, IETF
ICMPv6
ICMP for IPv6. Similar functionality to ICMPv4 but is used for IPv6 packets
Which two protocols function at the internet layer? (Choose two.)
ICMP, IP
Which of the following are protocols that provide feedback from the destination host to the source host regarding errors in packet delivery? (Choose two.)
ICMPv4, ICMPv6
Messaging
ICMPv4,ICMPv6,ICMPv6 ND
ICMPv6 ND
ICMPv6 Neighbor Discovery. Includes four protocol messages that are used for address resolution and duplicate address detection.
IPv6
IP version 6. Similar to IPv4 but uses a 128-bit address.
Internet Protocol
IPv4,IPv6,NAT
Increases efficiency
If a single segment is fails to reach its destination due to a failure in the network or network congestion, only that segment needs to be retransmitted instead of resending the entire data stream
Common computer protocols include the following requirements
Message encoding Message formatting and encapsulation Message size Message timing Message delivery options
communication methods have the following three elements in common:
Message source (sender),Message Destination (receiver), Channel
Message source (sender)
Message sources are people, or electronic devices, that need to send a message to other individuals or devices
Routing Protocols 2
OSPF,EIGRP,BGP
International Telecommunications Union-Telecommunication Standardization Sector (ITU-T)
One of the largest and oldest communication standards organizations. The ITU-T defines standards for video compression, Internet Protocol Television (IPTV), and broadband communications, such as a digital subscriber line (DSL).
Electronic Industries Alliance (EIA)
Organization is best known for its standards relating to electrical wiring, connectors, and the 19-inch racks used to mount networking equipment.
POP3
Post Office Protocol version 3. Enables clients to retrieve email from a mail server and download the email to the client's local mail application.
Network Communications Protocols
Protocols enable two or more devices to communicate over one or more networks. The Ethernet family of technologies involves a variety of protocols such as IP, Transmission Control Protocol (TCP), HyperText Transfer Protocol (HTTP), and many more.
REST
Representational State Transfer. A web service that uses application programming interfaces (APIs) and HTTP requests to create web applications.
TCP/IP Model Layer Application
Represents data to the user, plus encoding and dialog control.
Network layer source and destination addresses
Responsible for delivering the IP packet from the original source to the final destination, which may be on the same network or a remote network.
Data link layer source and destination addresses
Responsible for delivering the data link frame from one network interface card (NIC) to another NIC on the same network.
SMTP,POP3,IMAP
SFTP
SSH File Transfer Protocol. As an extension to Secure Shell (SSH) protocol, SFTP can be used to establish a secure file transfer session in which the file transfer is encrypted. SSH is a method for secure remote login that is typically used for accessing the command line of a device.
The IP packet contains two IP addresses
Source IP address, Destination IP address
SLAAC
Stateless Address Autoconfiguration. A method that allows a device to obtain its IPv6 addressing information without using a DHCPv6 server.
TCP/IP Model Layer Transport
Supports communication between various devices across diverse networks.
Destination IP address
The IP address of the receiving device, which is the final destination of the packet.
Source IP address
The IP address of the sending device, which is the original source of the packet.
Destination IPv4 address
The IPv4 address of the receiving device, FTP server: 192.168.1.9.
Source IPv4 address
The IPv4 address of the sending device, the client computer PC1: 192.168.1.110.
Application
The application layer contains protocols used for process-to-process communications.
Data Link
The data link layer protocols describe methods for exchanging data frames between devices over a common media
Network portion (IPv4) or Prefix (IPv6)
The left-most part of the address that indicates the network in which the IP address is a member. All devices on the same network will have the same network portion of the address.
Network
The network layer provides services to exchange the individual pieces of data over the network between identified end devices.
Destination data link address
The physical address of the NIC that is receiving the data link frame. This address is either the next hop router or the address of the final destination device.
Source data link address
The physical address of the NIC that is sending the data link frame.
Physical
The physical layer protocols describe the mechanical, electrical, functional, and procedural means to activate, maintain, and de-activate physical connections for a bit transmission to and from a network device.
Presentation
The presentation layer provides for common representation of the data transferred between application layer services.
Host portion (IPv4) or Interface ID (IPv6)
The remaining part of the address that identifies a specific device on the network. This portion is unique for each device or interface on the network.
Which delivery method is used to transmit information to one or more end devices, but not all devices on the network?
muliticast
Which type of communication will send a message to a group of host destinations simultaneously?
multicast
Which of the following statements are true regarding network layer and data link layer addresses? (Choose three.)
network layer addresses are logical and data link addresses are expressed as 12 hexadecimal digits. network layer addresses are physical and network layer addresses are logical. network layer addresses are either 32 or 128 bits in length
TCP/IP has two important aspects for vendors and manufacturers
open standard protocol suite, standards based protocol suite
What is the general term that is used to describe a piece of data at any layer of a networking model?
protocol data unit
What is the purpose of protocols in data communications?
providing the rules required for a specific type of communication to occur
internet assigned number authority (IANA)
responsible for overseeing and managing IP address allocation, domain name management and protocol identifiers for ICANN
internet society (ISOC)
responsible for promoting the open development and evolution of internet use throughout the world
internet architecture board (IAB)
responsible for the overall management and development of internet standards
BGP and OSPF are examples of which type of protocol?
routing
Which services are provided by the internet layer of the TCP/IP protocol suite?
routing protocols, messaging, internet protocol
What is the PDU associated with the transport layer?
segment
What is the process of dividing a large data stream into smaller pieces prior to transmission?
segmentation
What is used to determine the network portion of an IPv4 address?
subnet mask
the TCP/IP application layer includes several protocols that provide specific functionality to a variety of end user applications
the OSI model layers 5,6, and 7 are used as references for applications software developers and vendors to produce applications that operate on networks
OSI layer 3
the network layer, maps directly to the TCP/IP internet layer. this layer is used to describe protocols that address and route messages through an internet work
OSI layer 4
the transport layer, maps directly to the TCP/IP transport layer. this layer describe general services and function that provide ordered and reliable delivery of data between source and destination host
if the transport header is UDP
then it is a datagram
if the transport header is TCP
then jt is a segment
open systems interconnections (OSI) protocols
this is a family of protocols developed jointly in 1977 by the international organization for standardization (ISO) and the international telecommunications union (ITU).the OSI protocol also include a seven layer model called the OSI reference model. the OSI reference model categorizes the function of its protocols. today OSI us mainly know for its layered model. the OSI protocols have largely been replaced by TCP?IP.
Hypertext Transfer Protocol (HTTP)
this protocol governs the way a web server and a web client interact. HTTP defines the content and formatting of the requests and response that are exchanged between the client and server. both the client and the web server software implement HTTP as part of the application. HTTP relies on other protocols to govern how the messages are transported between the cilent server
internet protocol (IP)
this protocol is responsible for delivering messages from the sender to the receiver.IP is used by routers to forward the messages across multiple networks
Ethernet
this protocol is responsible for the delivery of messages from one NIC to another NIC on the same Ethernet local area network (LAN).
In computer communication, what is the purpose of message encoding?
to convert information to the appropriate form for transmission
What is the purpose of the sequencing function in network communication?
to uniquely label transmitted segments of data for proper reassembly by the receiver
Which layer of the OSI model defines services to segment and reassemble data for individual communications between end devices?
transport
True or false? Frames exchanged between devices in different IP networks must be forwarded to a default gateway.
true
Channel
This consists of the media that provides the pathway over which the message travels from source to destination.
Application Interface
This function contains information used for process-to-process communications between network applications. For example, when accessing a web page, HTTP or HTTPS protocols are used to communicate between the client and server web processes.
Sequencing
This function uniquely labels each transmitted segment of data. The receiving device uses the sequencing information to reassemble the information correctly. This is useful if the data segments are lost, delayed or received out-of-order. TCP provides sequencing services.
Addressing
This identifies the sender and the intended receiver of the message using a defined addressing scheme. Examples of protocols that provide addressing include Ethernet, IPv4, and IPv6.
Source MAC address
This is the data link address, or the Ethernet MAC address, of the device that sends the data link frame with the encapsulated IP packet. The MAC address of the Ethernet NIC of PC1 is AA-AA-AA-AA-AA-AA, written in hexadecimal notation.
TCP
Transmission Control Protocol. Enables reliable communication between processes running on separate hosts and provides reliable, acknowledged transmissions that confirm successful delivery.
here three types of data communications include:
Unicast,Multicast,Broadcast
UDP
User Datagram Protocol. Enables a process running on one host to send packets to a process running on another host. However, UDP does not confirm successful datagram transmission.
novel netware
a short lived proprietary protocol suite and network operating system developed by novell inc. in 1983 using the IPX network protocol. in 1995, novell adopted TCP/IP replace IPX
apple talk
a short lived proprietary protocol suite released by apple inc. in 1985 for apple devices. in 1995 apple adopted TCP/IP to replace apple talk.
Which protocol stack layer encapsulates data into frames?
data link
What process is used to receive transmitted data and convert it into a readable message?
decoding
Which logical address is used for delivery of data to a remote network?
destination IP address
What is the order of the two addresses in the data link frame?
destination MAC, source MAC
What types of standards are developed by the Electronics Industries Alliance (EIA)?
electric wiring and connectors
What is the name of the process of adding protocol information to data as it moves down the protocol stack?
encapsulation
What process is used to place one message inside another message for transfer from the source to the destination?
encapsulation
What is the process of converting information into the proper form for transmission?
encoding
True or False? Data Link addresses are physical so they never change in the data link frame from source to destination.
false
True or false? The right-most part of an IP address is used to identify the network that a device belongs to.
false
Which three are components of message timing?
flow control, access method, response timeout
Which step of the communication process is concerned with properly identifying the address of the sender and receiver?
formatting
This standards organization is responsible for IP address allocation and domain name management.
internet assigned numbers authority (IANA)
This standards organization is concerned with the Request for Comments (RFC) documents that specify new protocols and update existing ones.
internet engineering task force
The subnet mask (IPv4) or prefix-length (IPv6)
is used to identify the network portion of an IP address from the host portion.
What are two benefits of using a layered network model? (Choose two.)
it assist in protocol design, it prevents technology in one layer from affecting other layers
What is done to an IP packet before it is transmitted over the physical medium?
it is encapsulated in a layer 2 frame
Which message delivery option is used when all devices need to receive the same message simultaneously?
Broadcast
IMAP
Internet Message Access Protocol. Enables clients to access email stored on a mail server as well as maintaining email on the server.
IPv4
Internet Protocol version 4. Receives message segments from the transport layer, packages messages into packets, and addresses packets for end-to-end delivery over a network. IPv4 uses a 32-bit address.
Transport
The transport layer defines services to segment, transfer, and reassemble the data for individual communications between the end devices.
both TCP/IP and OSI model are commonly used when referring to protocols at various layers
because the OSi model separates the data link layer from the physical layer, it is commonly used when referring to these lower layers
What type of communication will send a message to all devices on a local area network?
broadcast
Address Resolution
ARP,Note:
TCP/IP Model Layer
Application,Transport,Internet,Network Access
BGP
Border Gateway Protocol. An open standard exterior gateway routing protocol used between Internet Service Providers (ISPs). BGP is also commonly used between ISPs and their large private clients to exchange routing information.
OSI Model Layer
Application, Presentation, Session, Transport, Network, Data Link, Physical
Increases speed
Because a large data stream is segmented into packets, large amounts of data can be sent over the network without tying up a communications link. This allows many different conversations to be interleaved on the network called multiplexing.
A web client is sending a request for a webpage to a web server. From the perspective of the client, what is the correct order of the protocol stack that is used to prepare the request for transmission?
HTTP,TCP, IP, Ethernet
ICMPv4
Internet Control Message Protocol for IPv4. Provides feedback from a destination host to a source host about errors in packet delivery.
SMTP
Simple Mail Transfer Protocol. Enables clients to send email to a mail server and enables servers to send email to other servers.
Session
The session layer provides services to the presentation layer to organize its dialogue and to manage data exchange.
Destination MAC address
When the receiving device is on the same network as the sending device, this is the data link address of the receiving device. In this example, the destination MAC address is the MAC address of the FTP server: CC-CC-CC-CC-CC-CC, written in hexadecimal notation.
WLAN
Wireless Local Area Network. Defines the rules for wireless signaling across the 2.4 GHz and 5 GHz radio frequencies.