Flashcards in ISDS 4120 Exam 2 Deck (88):
What does an application layer address using TCP look like?
-the application layer contains software that converts incoming and outgoing data from 1 format to another
The functions of the application layer?
-data access logic
Data Access Logic
-processing required to access the data
-often means database queries in SQL
-can be simple or complex
-presentation of information to the user and the acceptance of the user's commands
The division of software on clients versus servers for two tier architecture?
-the server is responsible for the data and the client, the application and presentation
The division of software on clients versus servers for three tier architecture?
-uses 3 sets of computers
-the software on the client customer is responsible for presentation logic
-application server is responsible for the application logic
-a separate database server is responsible for the data access logic and data storage
Where server name resolution is done?
What does TCP use to reassemble packets in the correct order?
The attributes of a sound wave?
-height of wave (decibels)
-waves per second (hertz)
-wavelength is the inverse of frequency
-wave direction (degrees) or the point at which the wave begins
-process of identifying what path to have a packet take through a network from sender to receiver
The 3 fundamental approaches to routing?
1.) centralized routing
2.) static routing
3.) dynamic routing
-all routing decisions are made by one central computer or router
-commonly used in host-behavior networks
-decentralized, all computers or routers make their own decisions
-self-adjusting, automatically adapt to changes in the network configuration
-decisions made in a fixed manner by individual routers or computers
-decisions made in a decentralized manner by individual computers
-attempts to improve network performance by routing messages over the fastest route possible
Different types of dynamic routing?
Distance Vector Dynamic Routing?
-routers count the number of hops along a route
Link State Dynamic Routing?
-based on the number of hops, circuit speed, and traffic congestion
What does the transport layer do to the messages?
-segmentation and reassembly
-end-to-end delivery of messages
How the capacity of a circuit is determined?
The different types of data?
-transmission involves discrete binary values
-0 or 1
-transmission involves continuous waves
The factors to consider when selecting media to be used in a network?
-type of network
-computers wait until the circuit is free and then transmit whenever they have data to send
-commonly used in ethernet lans
-in high-volume networks, many computers want to transmit, and the probability of a collision using contention is high
-very costly due to terms of throughput because they waste circuit capacity during the collision and require both computers to retransmit later
-controlled access prevents collisions and make more efficient use of the circuit
Between Contention and Collision, which one is better for different types of networks?
-is the process of sending a signal to a client computer that gives it permission to transmit
-clients store all messages that need to be transmitted
How an application layer address is translated to an IP address?
-server name resolution
-connect devices and include wires
-refers to the transmission characteristics of the circuit
-a circuit that's filled almost to its capacity and thus is the critical point that determines whether users get good or bad response times
-a switch connects all computers to 1 central computer that routes messages to the appropriate computer
-each node connects to exactly 2 other nods, forming a single continuous pathway for signals through each node
-connects all computers in a closed loop with each computer linked to the next
Full Mesh Network
-each network node (workstation or other device) is connected directly to all the others
-every computer is connected to every other computer
-least expensive and intelligent
-if a message comes in for a specific computer, it sends the message to all computers
-similar to hub
-learns based upon experience, where a specific computer is located
-most expensive and intelligent
-using protocols, know where every computer is located on a network
Hubs and Switches
-link cables from different devices
-acts as repeaters, reconstructing, and strengthening incoming signals
Types of Backbone Networks
-how the network works conceptually
-how the network is physically installed
Backbone Network Options
-most common type of BN used in the distribution layer
-use a star topology with 1 switch at its center
-switch serves each LAN
-inexpensive and fast
-not as flexible
-intended for use in large networks that have special requirements
VLAN Switches Advantages
-more flexible sub-netting
-better managed traffic flow, which may lead to faster performance
VLAN Switches Disadvantages
-may increase management when VLAN membership change
-move packets along the backbone on the basis of their network layer address
-most commonly used to connect different buildings on the same enterprise campus backbone network
Routed Backbone Description
-LANs are connected to a switch
-each backbone switch is connected to a router
-breaks the network into separate subnets
-segments the network
-typically used at core layer, but sometimes at distribution layer
Routed Backbone also called
Routed Backbones Advantages
Routed Backbones Disadvantages
-tend to be slower
-harder to manage
Different approaches to monitor connections on a network?
-simple network management tool (SNMP)
-process of operating, monitoring, and controlling the network to ensure it works as intended and provides value to users
Simple Network Management Tool SNMP
-a management network requires both hardware and software
-managed devices to monitor, collect, and transmit traffic reports and problem alerts
-network management software to store, organize, and analyze these reports and alerts
SNMP Managed Devices
-managed devices are more expensive than unmanaged devices because they have a CPU and software built into them
The definition and purpose of network segmentation
-breaking up large files into smaller segments
-may be passed individually to the application layer or after reassembly
The activities associated with each of the stages of network design?
-understand current and future network needs of various users, departments, and applications
-clients and servers
-circuits and devices
-examine available technologies to determine which meet or exceed needs
-if needs are difficult to estimate, build higher capacity
-baseline, geographic scope, app systems, network users, needs categorization
-relative costs of technologies are considered
-off the shelf, request for proposal
The definition and types of media access control?
-the controller works consecutively through a list of clients, first polling client 1, then client 2, and so on until all are polled
-can be modified to select clients in priority so that some get polled more often than others
-1 device starts the poll and passes it to the next computer on the multipoint circuit, until it reaches them all
The different layers of the backbone architecture?
-how users access network
-BN that connects access layer to core layer within building
-connects BNs between buildings and to WAN/Internet
-isn't affected by internet disruptions, more capatible
-allows secure remote access to a network via internet using PVCs that act like circuits
Options to improve backbone performance?
-choosing the best routing protocols
-upgrading or adding circuits
-move servers closer to end users, reduce traffic
-the development of a plan, goal, or vision for the future
Options to monitor and control a network
-designing for network performance
-performance and fault management
-end user support
Layers of the OSI Model?
1.) physical layer
2.) data link layer
3.) network layer
4.) transport layer
5.) application layer
-transmit the message
Data Link Layer
-moves a message from 1 device to another
1.) controls hardware
2.) formats the message
3.) error checking
-deciding where the message goes
1.) link app layer to network
2.) segmenting and tracking
3.) flow control
-users access to network, software to perform work
-HTTP, SMTP, DNS, FTP, DHCP, IMAP, POP, SSL
The 3 choices when outsourcing to the cloud and be able to match them to the grid
-software as a service (SaaS)
-platform as a service (PaaS)
-infrastructure as a service (IaaS)
Software as a Service SaaS
-all application components and associated hardware/software outsource
-based on multitenancy
Platform as a Service PaaS
-application logic and data are managed internally
-ex. microsoft azure
Infrastructure as a Service IaaS
-all hardware is outsourced