Internet Infrastructure (Part 2)

1. Domain name are assign because ip address number are difficult to remember.
2. The Last Segment = Suffix = Top-level Domain
3. The First Word = identify subcategory = Canonical name (CNAME)
4. Domain Name and ip address do not have permanantly related
5. Two name resolution service

• Domain Name System
• Windows Internet Naming Service

     6. DNS has 3 logical Component:

• computer searching for the ip, resolver
• server contain information, name server
• resolve domain name, namespace

     7. Discovering an ip address for a given domain = Address Resolution

         Process called = reverse mapping, reverse resolution

         network solution maintains servers = root servers

    8. Network  that support DNS ; primary name server,secondary name server(slave name server)
    9. The group of networks = name server's zone

        A zone can have a caching-only server that does not keep authoritative information

   10. Name server keeps entries for each domain name = resource record, DNS record

• Address: Identifies the ip address of a domain name
• CNAME: An alias that lets a host can be access
• Name Serve: Identifies the IP add. of the primary and secondary name server for domain
• Mail Exchanger: Identifies the mail exchanger on a domain
• Start Of Authority (SOA): Identifies the ip address of the DNS server is the primary authority for a domain

  11. DNS began envolving in 1983 =  Host Table

  12. Directory Server = store info. about people, host and other resource

  13. Directory Access Protocol(DAP); X.500 = to allow directory service communicate with each other

  14. Lightweight Directory Access Protocol(LDAP) = to streamline the process

X.500 And LDAP Implementation

• eDirectory(Novell Netware)
• active Directory(Windows)
• open directory(apple)
• apache directory servere 
• redhat directory serve

  15. LDAP was design to run over TCP and can be used on the internet or intranet

  16. LDAP has less code than DAP

  17. X.500 specifies how global directories can be structured

Advantage of X.500 and LDAP

• Synchronization=directory on one server can be synchronize with the directory on another server
• Replication=part of directory database on one server can copy itself to another server
• Scalability=there is no limit to the size which the directory can grow

  Cache Servers

  Improve performance by caching data so that the internet is reduced

  Mirrored Servers

  Carried the same data and service as another server

PPP(Point to Point protocol)

  •intranet access point by telephone line

PPoE(Point to Point Over Ethernet)

  •adapts PPP to work with Ethernet

ISDN(Integrated Service Digital Network)

  •tech. develop in 1980, uses regular telephone line or dialup connection

Broadband

  •refer to any type of networking that carries more than one type of transmission

T Lines & E Lines
•introduce in 1960
•use multiplexing, a process of dividing a single channel to multiple channel that can carry audio, video, or other.
•T lines- America; E Lines- European

X.25 And Frame Relay
• packet-switching communication protocol design for long distance data transmission
• both use PVC (permanent virtual circuit)

ATM(Ansyncronous Transer Mode)
• fast network tech. that can be used with LANs as well as WANs
SVCs(Switched Virtual Circuit)
• point to point connc. that depend on the atm to decide the best path to send data
Mesh Topology
• provides multiple point-to-point links between router in wide area network.
• router search out multiple path and determine the best path

Video Pre-Production

Introduction

Video production is concerned with non-broadcast program making. Productions are recorded closed-circuit on videotape, distributed and viewed by a small audience


The Production Team

•Production group vary in size, according to the organization and the complexity of the production
•Titles and responsibilities differ.
•In some groups there are strict demarcations, while in smaller units work is shared

Types Of Video Production

•Live Event Coverage
•Instructional Video
•Informational Video
•Corporate Video

Video Pre-Production Process

• Idea Generation 
• Treatment / Plan 
• Storyboard and Scripts 
• Shot List and Running Sheet 
• Location 
• Casting 
• Budgeting 

Idea Generation
Different Genres
A genre is a type of text, a format for communicating information.
Here are some examples:
- comedy
- action
- mystery
- science fiction
- documentary
- music video
- commercial.

Treatment/Plan
The treatment is a written document that summarizes the story line (plot) of the video or film.

Usually the writer and the director get together to convey the idea to a producer.

Storyboard

•A series of diagrams that are used to depict the composition of a video segment.
•Each diagram consists of: a sketch of the video image; a brief description of the visual; notes for the camera operator; the details of the desired audio that will accompany the visual; and an estimate of how long the segment will be.

Script Writing

•Planning is an essential part of production and the script forms the basis for that plan
•It helps the director to clarify ideas and to develop a project that will work
•It helps to coordinate the production team

Shotlist

•Working date
•Title of showy
•Shot code system
•Description of shot
•Camera framing details
•Length of shot (roughly)
•Any notes

Shotlist Code

•ECU : Extreme close up
•CU : Close up
•MS : Medium shot
•LS : Long Shot
•VLS : Very long shot
•ELS : Extreme long shot

Running Sheet

•Working date
•Equipment list
•Cast list
•Props list
•Schedule for the day
•Any important reminders / notes

Location

•Location refers to the place that you video tape the project. There are generally two types of location:
1) sets
2) remote location

Casting

•Casting is the process of determining which person will play each role in the project.

Budgeting

•Stick to budget no matter what
•Make sure everyone knows what the budget limits

•Keep track of every expenses

Audio Equipment

Introduction Of Audio System
Modern audio system creates
sound by utilizing modern
electronic ingredients
• Three elements of an audio system:
– Source
– Amplification
– Output

High Fidelity (Hi-fi)


• Fidelity is the accuracy with which a system reproduces the original signal fed to it.
• High Fidelity is the technique of recording, broadcasting and reproducing sound to match the
  characteristic of the original sound
• The goal of hi-fi is to reproduce an identical set of sound vibration
• It must be able to span the entire human hearing frequency range


Microphones


• Microphones are transducers which detect sound signals and produce an electrical image of the
sound, i.e., they produce a voltage or a current which is proportional to the sound signal.
• The most common microphones for musical use are dynamic,
ribbon, or condenser microphones.
• Besides the variety of basic mechanisms, microphones can be designed with different directional patterns

Type Of Enclosure


The production of a good high fidelity loudspeaker requires that the speakers be enclosed because
of a number of basic properties of loudspeakers.
• Just putting a single dynamic loudspeaker in a closed box will improve its sound quality dramatically.

Digital Audio And Sound Application

Sample Rate
Taking more samples allows the “sampling" process to more closely approximate the curve of the original, analog wave, and therefore get closer to reproducing the sound digitally

Also known as Sampling Frequency
E.g:

• 44KHz: CD quality sound
• 22KHz: OK for music
• 11KHz: OK for voice
• 5 KHz: A.M. radio

Sample Size

• Sample size is either 8-bit or 16-bit; this naming scheme describes the amount of computer space allotted to store data gathered in each sample
• Also known as Bit Depth / Sample Resolution
• The more bits used to represent the amplitude, the greater the dynamic range that can be represented

Analog To Digital Converter

1. Here is an analog sound wave. Analog sound is continuous variation in air pressure.

2. To digitize sound, samples are taken at even intervals of time.

3. These samples are trimmed to the nearest value and encoded in binary.

Sound File

• Sound files contain large amounts of data, and uncompressed, they are huge.
• A sound file generally has audio data and metadata
• Audio data is the sound that you hear
• Metadata can include the name of the sound file, its size, duration, number of channels, resolution or sample size (in bits), sampling rate (in kilohertz), type of compression, information about licensing or streaming, special instructions, or other text or graphics.

Amplitude Envelope

• When a mechanical musical instrument produces sound, the relative volume of the sound produced changes over time
• The way that this varies is different from instrument to instrument
• Example: A guitar, by contrast, is loudest immediately after it is played, and fades with time
• Shaping of the sound's amplitude profile is realized with an "ADSR" (Attack Decay Sustain Release) envelope model
• The ADSR envelope is a parameter used in synthesizers to control the sound produced

• Attack: How quickly the sound reaches full volume after the sound is activated (the key is pressed).
• Decay: How quickly the sound reduces in volume after the initial peak.
• Sustain: The "constant" volume that the sound takes after decay until the note is released.
• Release: How quickly the sound fades after the end of the note (the key is released). Often, this time is very short.

Stereophonic

• It is the study of multichannel, 3D sound and the electronic audio equipment used to reproduce it.
• It is a way to recreate a sound stage, including the ability of the listener to determine the original source location of specific sounds.
• (stereois ‘3D’ and phonicis ‘the science of sound’)
• Before stereophonics, there was monophonicwhich only utilized one channel of recording and playback

Channels

• A channel is a single path for transmitting electrical signal
• One channel audio system = 1 source, 1 recording channel, 1 amplifier & 1 speaker
• Multichanneling makes several recordings of the same sounds
• Its like having two or more tape running simultaneously
• The channels are recorded with more than one microphone thus the channels are not exact duplicates of each other.

Creating Stereo

• Stereo theoretically separates each sound source and places it in 3 dimensions
• E.g. Guitar on the left, piano to the right and a singer centered.
• Two microphones are recording the sound pressures which placed at a distance from each other
• Usually reside in front of instruments or voices being recorded
• Each microphone is recording one track on the same audio tape. The two tracks then played by two separate speakers.

Law of the First Wave Front

• The first sound to arrive at the ears determines the perception of direction to the source.

Reverberation

• Reverberation consists of the random sounds that surround the listener in a live concert hall experience
• It is the hidden equation in stereo imaging
• These are the sounds that are launched out to the audience, auditorium, concert hall or studio and are bounced back to the microphones that are recording two tracks.

Surround sound

• Surround sound is a system that enhances the spatial imaging capabilities of the playback system
• To create a sound field that can surround the audience with direct and ambient sound from all directions
• Example:  Pro Logic, 4 Channel and 5, Speaker-Dolby Digital

Speech Synthesis

• Speech synthesis is the artificial production of human speech.
• It can be implemented in software or hardware.
• Speech synthesis systems are often called text-to-speech (TTS) systems in reference to their ability to convert text into speech
• TTS is composed of two parts: a front end and a back end