Networking chapter 3

Internet Protocol (IP)

- Receives message segments from the transport layer - Packages messages into packets - Addressed packets for end-to-end delivery over an Internetwork

Post Office Protocol version 3 (POP3)

-Enables clients to retrieve email from a mail server -Downloads email from the mail server to the desktop (Application Layer, Email)

protocol suite

A group of inter-related protocols necessary to perform a communication function is called ______ which is implemented by hosts and networking devices in software, hardware or both.

unicast

A one-to-one delivery option is referred to as

Hypertext Transfer Protocol (HTTP)

A set of rules for exchanging text, graphic, images, sound, video, and other multimedia files on the World Wide Web

Trivial File Transfer Protocol (TFTP)

A simple, connectionless file transfer protocol A best-effort, unacknowledged file delivery protocol Utilizes less overhead than FTP

Network Access Layer

At the ________, the TCP/IP protocol suite doesn't specify which protocols to use when transmitting over a physical medium.

describes the handoff from the internet layer

At the network access layer, the TCP/IP model _______ to the physical network protocols

Internet Corporation for Assigned Names and Numbers (ICANN)

Based in the United States, coordinates IP address allocation, the management of domain names, and assignment of other information used TCP/IP protocols

Electronic Industries Alliance (EIA)

Best known for its standards related to electrical wiring, connectors, and the 19-inch racks used to mount networking equipment.

Enhanced Interior Gateway Routing Protocol (EIGRP)

Cisco proprietary routing protocol Uses composite metric based on bandwidth, delay, load and reliability

Application Layer (OSI)

Contains protocols used for process-to-process communications

Network Access Layer (TCP/IP)

Controls the hardware devices and media that make up the network. Equivalent to the physical and data link layers of the OSI model.

Transport Layer (OSI)

Defines services to segment, transfer, and reassemble the data for individual communications between the end devices.

Ethernet

Defines the rules for wiring and signaling standards of the network access layer

OSI Model

Describes the interaction of each layer with the layers directly above and below it

Internet Layer (TCP/IP)

Determines the best path through the network. Equivalent to the network layer of the OSI model.

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.

Dynamic Host Configuration Protocol (DHCP)

Dynamically assigns IP addresses to client stations at start-up. It allows the addresses to be re-used when no longer needed

Bootstrap Protocol (BOOTP)

Enables a diskless workstation to discover its own IP address, the IP address of this on a server on the network, and a file to be loaded into memory to boot the machine; it is currently being replaced by DHCP.

User Datagram Protocol (UDP)

Enables a process running on one host to send packets to a process running on another host Does not confirm successful datagram transmission

Internet Message Access Protocol (IMAP)

Enables clients to access email stored on a mail server Maintains email on the server

Simple Mail Transfer Protocol (SMTP)

Enables clients to send email to a mail server, it also enables servers to send email to other servers

Transmission Control Protocol (TCP)

Enables reliable communication between processes running on separate hosts Reliable, acknowledged transmissions that confirm successful delivery

sounds, light waves, or electrical impulses

Encoding between hosts must be in an appropriate format for the medium. Messages sent across the network are first converted into bits by the sending host. Each bit is encoded into a pattern of _____, _______ or ________ depending on the network media over which the bits are transmitted. The destination host receives and decodes the signals in order to interpret the message.

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).

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 may go on with the conversation. Hosts on the network also have rules that specify how long to wait for responses and what action to take if one of these occurs.

Network access layer and application layer

In the OSI Model, the first layer of the TCP/IP layer protocol is divided to describe discrete functions that occur at those layers.

Data Link Layer (OSI)

Its protocols describe methods for exchanging data frames between other devices over a common media.

Physical Layer (OSI)

Its protocols describe the mechanical, electrical, functional, and procedural means to activate, maintain, and de-activate physical connections for bit transmission to and from a network device.

a frame

Just as a letter is encapsulated in an envelope for delivery, so too are computer messages. Each computer message is encapsulated in a specific format, called _______, before it is sent over the network. this acts like an envelope; it provides the address of the destination and the address of the source host

Open Shortest Path First (OSPF)

Link-state routing protocol Hierarchical design based on areas Open standard interior routing protocol

Transport Layer (OSI)

Maps directly to the TCP/IP Transport Layer

Vendor-Specific protocol stack

Most protocol models describe a(n)

Physical

OSI layer 1

Data Link

OSI layer 2

network

OSI layer 3

Transport

OSI layer 4

Session

OSI layer 5

Presentation

OSI layer 6

Application

OSI layer 7

International Telecommunications Union-Telecommunication Standardization Sector (ITU-T)

One of the largest and oldest communication standard organizations. The ITU-T defines standards for video compression, Internet Protocol Television (IPTV), and broadband communications, such as a digital subscriber line (DSL).

Institute of Electrical and Electronics Engineers (IEEE, pronounced "I-triple-E") -

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.

An identified sender and receiver Common language and grammar Speed and timing of delivery Confirmation or acknowledgment requirements

Protocols must account for the following requirements:

Point-to-Point Protocol (PPP)

Provides a means of encapsulating packets for transmission over a serial link

Address Resolution Protocol (ARP)

Provides dynamic address mapping between an IP address and a hardware address

Internet Control Message Protocol (ICMP)

Provides feedback from a destination host to a source host about errors in packet delivery

Presentation Layer (OSI)

Provides for common representation of the data transferred between application layer services.

Interface Driver

Provides instruction to a machine for the control of a specific interface on a network device

Session Layer (OSI)

Provides services to the presentation layer to organize its dialogue and to manage data exchange.

Application Layer (TCP/IP)

Represents data to the user, plus encoding and dialog control. Equivalent to the top three layers of the OSI model.

Telecommunications Industry Association (TIA)

Responsible for developing communication standards in a variety of areas including radio equipment, cellular towers, Voice over IP (VoIP) devices, satellite communications, and more. Figure 2 shows an example of an Ethernet cable meeting TIA/EIA standards.

Internet Assigned Numbers 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 growth/improvement of Internet use throughout the world.

Internet Architecture Board (IAB)

Responsible for the overall management and development of Internet standards.

File Transfer Protocol (FTP)

Sets rules that enable a user on one hoset to access and transfer files to and from another host over a network. It is a reliable, connection-oriented, and acknowledged file delivery protocol.

Hypertext Transfer Protocol (HTTP), Transmission Control Protocol (TCP), and Internet Protocol (IP)

Some common networking protocols are ________, _________ and _________.

proprietary

Some protocols are ________ which means one company or vendor controls the definition of the protocol and how it functions.

Transport Layer (TCP/IP)

Supports communication between various devices across diverse networks.

Application Layer Name System: DNS Host Config: BOOTP, DHCP Email: SMTP, POP, IMAP File Transfer: FTP, TFTP Web: HTTP Transport layer: UDP, TCP Internet Layer: IP Support: ICMP Routing Protocols: OSPF Other: IP, NAT Network Access Layer: ARP, PPP, Ethernet, Interface Drivers

TCP/IP Protocol Suite and communication process categories Application Layer Name System: (input) Host Config: (input) Email: (input) File Transfer: (input) Web: (input) Transport layer: (input) Internet Layer: IP Support: (input) Routing Protocols: (input) Other: (input) Network Access Layer: (input)

the Internet model

The TCP/IP Protocol Model for internetwork communications was created in the early 1970s and is sometimes referred to as

Application

The TCP/IP _______ Layer includes a number of protocols that provide specific functionality to a variety of end user applications

Network

The ______ layer is used to describe protocols that address and route messages through an interwork

network

The ________ access layer protocols are responsible for delivering the IP packet over the physical medium.

TCP/IP protocol suite

The _________ is an open standard, meaning these protocols are freely available to the public, and any vendor is able to implement these protocols on their hardware or in their software.

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.

The benefits to using a layered model to describe network protocols and operations include:

a publicly available set of RCFs

The definitions of the standard and the TCP/IP protocols are discussed in a public forum and defined in

Application, Transport, Internet, and Network Access Layers.

The individual protocols are organized in layers using the TCP/IP protocol model:

transport; network

The key similarities between the OSI and TCP/IP model is in the _________ and ________ layers

encapsulation, De-encapsulation

The process of placing one message format (the letter) inside another message format (the envelope) is called __________. __________ occurs when the process is reversed by the recipient and the letter is removed from the envelope. (this is also true of electronicss)

protocols

The sending of this message, whether by face-to-face communication or over a network, is governed by rules called __________ which are specific to the type of communication method occurring.

standards

The use of _______ in developing and implementing protocols ensures that products from different manufacturers can interoperate successfully. If a protocol is not rigidly observed by a particular manufacturer, their equipment or software may not be able to successfully communicate with products made by other manufacturers.

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.

Transport layer

This layer describes general services and functions that provide ordered and reliable delivery of data between source and destination hosts

Protocol Model

This type of model closely matches the structure of a particular protocol suite. The TCP/IP model is a protocol model because it describes the functions that occur at each layer of protocols within the TCP/IP suite. TCP/IP is also used as a reference model.

Reference Model

This type of model provides consistency within all types of network protocols and services by describing what has to be done at a particular layer, but not prescribing how it should be accomplished. The OSI model is a widely known internetwork reference model, but is also a protocol model for the OSI protocol suite.

flow control

Timing also affects how much information can be sent and the speed that it can be delivered. If one person speaks too quickly, it is difficult for the other person to hear and understand the message. In network communication, source and destination hosts use ______ methods to negotiate correct timing for successful communication.

Network Address Translation (NAT)

Translates IP addresses from a private network into globally unique public IP addresses

Domain Name System (or Service) [DNS]

Translates domain names, such as cisco.com, into IP addresses

False

True or False: The OSI and TCP/IP do not differ in how they relate to the layers above and below each layer

multicast

When a host needs to send messages using a one-to-many delivery option, it is referred to as this which is the delivery of the same message to a group of host destinations simultaneously.

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.

Encoding; Decoding

________ is the process of converting information into another acceptable form, for transmission. ________ reverses this process in order to interpret the information.

Open standards

__________ encourage interoperability, competition, and innovation. They also guarantee that no single company's product can monopolize the market, or have an unfair advantage over its competition.

Standards Organizations

___________________________ are usually vendor-neutral, non-profit organizations established to develop and promote the concept of open standards.

standards-based protocol

a process that has been endorsed by the networking industry and approved by a standards organization.

size

another rule of communication is

an open standard

because the TCP/IP model is ______, one compony doesn't control the definitions

Access Method

determines when someone is able to send a message. It is necessary for computers to define this to know when to begin sending messages and how to respond when collisions occur (similar to two people talking at the same time).

Ethernet

is a network access protocol that describes two primary functions: communication over a data link and the physical transmission of data on the network media. Network access protocols are responsible for taking the packets from IP and formatting them to be transmitted over the media.

HTTP (Hypertext Transfer Protocol)

is an application protocol that governs the way a web server and a web client interact. It defines the content and formatting of the requests and responses that are exchanged between the client and server. Both the client and the web server software implement it as part of the application. It relies on other protocols to govern how the messages are transported between the client and server.

IP

is responsible for taking the formatted segments from TCP, encapsulating them into packets, assigning them the appropriate addresses, and delivering them to the destination host.

TCP (Transmission Control Protocol)

is the transport protocol that manages the individual conversations. It divides the HTTP messages into smaller pieces, called segments. These segments are sent between the web server and client processes running at the destination host. It is also responsible for controlling the size and rate at which messages are exchanged between the server and the client.

Network Layer (OSI)

provides services to exchange the individual pieces of data over the network between identified end devices.

broadcast

represents a one-to-all message delivery option.

Functions and Services

the osi model provides an extensive list of _________ that can occur at each layer

Access Method Flow Control Response Timeout

the rules of engagement for message timing.

OSI layers 1 and 2

these discuss the necessary procedures to access the media and the physical means to send data over a network

break the message into smaller pieces; break a long message into individual pieces that meet both the minimum and maximum size requirements

when a long message is sent from one host to another over a network, it is necessary to ________. The rules that govern the size of the pieces, or frames, communicated across the network are very strict. They can also be different, depending on the channel used. Frames that are too long or too short are not delivered. The size restrictions of frames require the source host to ______. The long message will be sent in separate frames, with each frame containing a piece of the original message. Each frame will also have its own addressing information. At the receiving host, the individual pieces of the message are reconstructed into the original message.