cctv endorsement manual
TRANSCRIPT
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CCTV Endorsement
Inst: Earl MontouteFosp, Foi, Fot, CFot, CVQ-L4.
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A Little bit of history.
Light is one of the basic and greatest natural phenomena, vital not onlyfor life on this planet, but also very important for the technicaladvancement.
It would be fair at this stage, however, to give credit to at least a fewmajor scientists in the development of physics, and light theorists inparticular, without whose work it would have been impossible to attaintodays level of technology.
Isaac Newton was one of the first physicists to explain many naturalphenomena including light.
August Fresnel also performed some very convincing experiments thatclearly showed that light has a wave nature.
James Clerk Maxwell, who in 1873 asserted that light was a form ofhigh-frequency electromagnetic wave, his theory predicted the speed of
light as we know it today: 300,000km/s.
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A Little bit of history.
Heinrick Hertz was the scientist that discover the phenomena
of Frequency.
In explaining the concepts of the lenses used in CCTV, we will
be using, most of the time, the wave theory of light, but we
should always have in mind that there are principles like the
CCD chips operation, for example, base on the light particle
behavior.
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Hardware Basics
Today we use the term camera in film, photography, television,
multimedia. Cameras project images onto different targets, but they
all use light and lenses.
To understand CCTV you do not need to be an expert in cameras
and optics, but it helps if you understand the basic concept.
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Hardware Basics
Types of Cameras used by CCTV systems.
Dome Cameras.
Bullet Cameras.
Pan-Tilt-Zoom.
Covert Cameras.
Miniature Cameras.
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Hardware Basics
Camera Housings.
In order to protect the cameras from environmental influences
and /or conceal their viewing direction, we use camera housing.
Camera housings can be very simple and straightforward toinstall and use, they are also available in all shapes and sizes,depending on the camera application and length.
Nowadays, CCD cameras are getting smaller, and so are zoomlenses, as a consequence housing are becoming smaller too.
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Hardware Basics
Lighting in CCTV
Most of the CCTV systems with outdoor cameras use both day and night lightsources for better viewing.
Systems for indoor applications use, obviously indoor ( artificial ) light source,although some may mix with daylight, as when sunlight penetrates through a
window.
Artificial light source falls into three main groups.
Sources that emit radiation by incandescent-such as candles, electric lamps.
Sources that emit radiant energy as a result of an electrical discharge through agas or vapor-neon lamp, sodium and mercury vapor lamp.
Fluorescent tubes.
The last two group are very tricky for color cameras, special attention should bepaid to the color, temperature and white balance capability of the cameras usedwith such light.
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Hardware Basics
Infrared cameras technologyWhen events need to be monitored at night, B/W cameras can be used inconjunction with infrared illuminator.
Infrared light is used because B/W CCD cameras have very goodsensitivity in and near the infrared region. These are the wavelengthslonger than 700 nm.
The two typical infrared wavelengths used with halogen lampilluminators are: one starting from around 715nm and the other fromaround 830nm.
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Hardware Basics
Lenses utilized for CCTV systems.
Fixed lenses
Vari-focal lenses.
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Hardware Basics
Power supply for CCTV operation.
A typical CCD camera consumes between 3 and 4 W of energy, thismeans that a 12 V DC camera needs no more than 300mA of currentsupply.
A 24V DC camera needs no more than 200mA, As the technologyimproves, cameras will consume less current. When powering a
number of cameras from a central power supply, it is important to takethe voltage drop into account and not to overload the supply.
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Recorders- 3.0
Today it seems that recording CCTV video on VCR tapes is nearly over.Five years ago VCRs were still around in big numbers, and DVRs wereonly starting to appear, today this ratio is reversed.
So what are the real benefits of using DVRs in CCTV, as opposed to
VCRs?
First, with the VCRs analog method there is no direct and quick accessto the desired camera, except when using a reasonably quick alarmsearch mode (available on most TL VCRs).
In VCRs the information is stored in an analog format and cannot befurther processed, the VCR recording video quality is always lower thanthe actual original source.
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Recorders- 3.0
Initially, in CCTV, attempts were made to implement digital videorecording on a digital audio tape (DAT ) format. Hard disks have a muchhigher through-output than other digital storage media and highercapacity.
What was a problem only a few years ago- length of recording , thesedays is no longer such. Hard disk with capacities of 300GB are readilyavailable and DVRs with internal capacities of 1200 GB ( 1.2 TB ) arenot a rarity.
Multi-week recording of a number of cameras is no longer a problem.
Hard disk drives (HDD) now have fast access time and by using goodcompression it is possible to record and play back multiple images fromone- in real time ( meaning Live video rate).
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Recorders- 3.0
How many days or weeks of video recording can be stored on a 300GB,for example, depends first on the type of compression and quality ofimages elected for such compression. Also, an important factor would beif the recording were made permanent or if it was based on video motion
detection.
The latter one has become very popular in CCTV as it extends therecording capacity at least two or threefold. Certainly, extending theHard drive storage is also possible, but providing redundancy ( safety) as
well might be an important request by a customer.
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Main Monitor Panel
Camera Snapshot
Screen Division
Date / Time
Message
Alarm on/off Video Backup
Screen lock
P/T/Z
Video Playback
Camera name
Recorded Time
Minimumclick to minimize the main panel
Exit Buttonclick to exit this Program
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Cable Design
PlenumCable rating or space between a false floor or ceiling.
RiserVertical shaft between floors.
Cable Markings.
Wire Insulation / Color Code.
Twists- helps to cancel out EMI generated by voltage used to sendsignal over the wire.
Wire Gaugecopper wire diameter is often measured by a unitcalled AWG.
Solid Conductor Vs Stranded Conductors.
Cable Length
UTP Category 3 / 16Mhz, Cat5 / 100Mhz, Cat6 / 250Mhz
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Cabling and the need for Speed
Types of Communications media ( cable ).
Twisted-Pair cable
Unshielded Twisted-Pair ( UTP)
Shielded Twisted-Pair ( STP)
Screened Twisted-Pair ( ScTP )
Optical-Fiber Cable (FO ).
All UTP, STP and ScTP Category 3, 5, 5e and 6 follows the samestandard from ANSI/TIA/EIA/568-B,-A
Coaxial Cable / RG-58, RG-59, RG-6U
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Types of Cables
There are four major types of communication medium which are
available for CCTV networking today. They are:
UTP
STP/ ScTP
Coaxial
Fiber Optic
It is important to distinguish between backbone cables and horizontal
cables.
Backbone cables connect network equipment such as servers, switches,and routers and connect equipment rooms and communication closets.
Horizontal cables run from the communication closet to the wall
outlets.
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Transmission Lines
In the Telecommunication Industry the most important sector in your
network is the medium or Transmission Lines. There are various typesof Transmission lines used base on the application used in the network.
The most commonly used ones are Fiber Optic, Ethernet Cables and
Coax Cables
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Transmission Lines
Fiber Optic Cables are divided into two main groups, SMF and MMF.
SMF- used for high speed and long distance transmission, yellow in
color and have a core size of 9 microns / 125 microns cladding size.
MMF- used for short distance and backbone application, orange, slate
and light blue in color, have a core size of 50 micron and 62.5 micron /
125 micron in cladding size.
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Transmission Lines
Ethernet Cables are the most commonly used in today networks, they
divided into four main category with transmission speed and
bandwidth.
Cat 310Mhz10Mbps ( voice )
Cat 5100Mhz100Mbps
Cat 5e150Mhz100Mbps
Cat 6200Mhz1000Mbps1Gbps
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Transmission Lines
Coaxial Cable has been around since local area networking was in its
infancy, it is well shielded, and has a high bandwidth capabilities and
low attenuation and is easy to install.
RG 618 AWG75 ohmssolid
RG 5920 AWG75 ohmssolid
RG 5820 AWG50 ohms - solid
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CCTV Connectors
RJ45- This connector is mainly used in IP application where
Ethernet technology is used to operate the Network.
BNCThis type of connector is the most commonly used one in
today application.
Video Balun is used where Ethernet Cables are installed instead ofCoax Cables
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Computer Network systems.
Bandwidth-does it means maximum frequency or data rate?
Frequency-:
The number of cycles completed per unit of time / cycle takes onesecond to complete ( hertz ).
Data rate:
Bandwidth is a function of three elements- distance, frequency andSNR.
Decibels (db) it is rather express as a ratio of sound pressure IL(db)=10log10 P2/P1
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Computer Network systems.
Standardizes Codes.
ANSI / TIA / EIA -568B/A Commercial Building TelecomCabling.
ANSI / TIA / EIA569 Commercial Pathway and Space.
ANSI/TIA/EIA570 Residential Cabling.
ANSI/TIA/EIA - 606 Administration infrastructure of CommercialBuildings
ANSI/TIA/EIA607 Commercial buildings Grounding.
ANSI/TIA/EIA758 Customer-owned outside plant Cabling.
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Computer Network systems.
IEEE 802.3 Ethernet Standard.
Ethernet Designation Codes
10Base-5 10Mbps, Coaxial 75ohm max 500m.
10Base-2 10Mbps, Coaxial 50ohm, RG58 Max 185m.
10Base-36 10Mbps, broadband, Max 3,600m
10Base-T 10Mbps, Cat 3, UTP Max 100m(outside plant 1800ft) .
100Base-TX 100Mbps Cat 5 UTP Max 100m.
100BaseT4 four Cable pair Cat 3 Max 100m.
10BaseFB 10Mbps, MMF Backbone, Max 2km.
10BaseFL 10Mbps MMF Fiber Link, Max 2km. IEEE 802.4 Token Bus..
IEEE 802.5 Token Ring..
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Computer Network systems.
Standards and Specifics Organization.
ANSIAmerican National Standards Institute
EIAElectronic Industrial Alliance
TIATelecommunication Industry Association
ITU-TInternational Telecommunication Union-Telecommunication Standardization Sector.
OSIOpen System Interconnection
Application
Presentation
Session Transport
Network
Data Link
Physical ----T1 , E1, SONET,ATM.
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Computer Network systems.
The Cable.
Horizontal and Backbone Cables:
The terms horizontal cable and backbone cable have nothing to do withthe cable physical orientation toward the horizon. Horizontal cables runbetween a cross-connect panel in a wiring closet and a wall jacks.
Backbone cable run between wiring closets and the main cross-connectpoints of a building ( equipment room).
Horizontal Cables:
Horizontal runs are most often implemented with 100-ohm, four-pair,
unshielded twisted-pair (UTP) solid-conductor cable The standard alsoprovides for horizontal cabling to be implemented using 62.5/125-micron or 50/125-micron multimode optical fiber
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Backbone Cables:Backbone cables can be implemented using 100-ohn UTP, 62.5/125-micron or 50/125-micron multimode optical fiber, or 8.3/125-micronsingle-mode optical fiber.
Optical fiber is the preferred installation medium because of distancelimitation associated with copper wiring.
Modular patch Cables:
Modular patch cables are used to provide the connection between field-terminated horizontal cables and network-connectivity devices such asswitches and hubs and connection between the wall-plate jack and
network devices such as computersWhereas horizontal UTP cables contain solid conductors, patch cords aremade with stranded conductors because they are more flexible.
Computer Network systems.
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Computer Network systems.
UTP-RJ45 Modular plugs & modular jackUTP-RJ45 & RJ11 Modular plugs and modular jacks are high speedEthernet Hardware used in today networks. The UTP-RJ45 & RJ11Modular plugs are terminated at the end of the Ethernet Cables using acrimper.
The UTP-RJ45 & RJ11 Modular Jacks are terminated using a punch-down tool. The RJ45 Modular Plugs and Modular Jacks are design witha 8 pin slot in the Plugs & Jacks to accommodate the 4pair EthernetCable. ( data, Voice, video ) The RJ11 Modular Plugs & Modular Jacks
are design with a 4 pin slot in the plugs & Jacks to accommodate lowerspeed Ethernet Cables. ( Voice )
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Computer Network systems.
Cable Pathway.ConduitConduit is pipe, it can be metallic or nonmetallic, rigid or flexible and itruns from a work area to a wiring closet It also runs from the top orceilings to the 2 x 4 ,4 x 4 boxes. One advantage of using conduit to
hold your cable is that it may already exit in your building. A drawbackto conduit is that it provides a finite amount of space to house cables.
Cable TraysAs an alternative to conduit, cable trays can be installed to route your
cable, they are typically wire racks specially designed to support theweight of a cable infrastructure. Cable trays provide an ideal way tomanage a large number of horizontal cable runs.
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Computer Network systems
RacewaysRaceways are special type of conduit used for surface mountinghorizontal cable and are usually pieced together in a modular fashionwith connectors provided by the vendors .
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Computer Network systems.
The Network topology refers to the physical layout of the nodes andhubs that make up the network. The right topology can affects the typeof network equipments e.g. - Cabling, growth path and networkmanagement
The three main Topology Categories are:
Star
Bus
Ring
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Star TopologyA Star topology is implemented when all computers are connected to asingle or centralized point. This point is usually a hub.
Bus TopologyThe Bus topology is the simplest network of all three topology. It isalso known as a Linear bus, all computers are connected to a contiguouscable. Computers in a bus topology listen only for transmissions fromother computers, they do not repeat or forward the transmission on toother computers.
Ring Topology.A Ring topology required that all computers be connected in acontiguous circle, it has no ends or hub.
Computer Network systems.
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Computer Network systems.
The common networking technologies today can all used either UTP orOptical Fiber. Today network technologies / Network Archit.
Ethernet
Token Ring.
FDDI
ATM
EthernetEthernet is the most common mature of all the network architectures, it isused in over 80% of all network installation. Ethernet technology has adesignated numbering code to help Techs and Engineers about the varioustransmission rates. Ethernet has been updated to support speeds of 100Mbpsand 1000Mbps, currently 10Gigabit Ethernet is being deployed over opticalfiber and research is progressing to make it available over UTP. Commonlyused Ethernet Designated Codes. 10Base-T, 10Base-FL, 100Base-TX,100Base-FX, 1000Base-T,-SX,-TX,-LX, 10Gbase,10Gbase-T
k
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Computer Network systems.
Token Ring TechnologyDeveloped by IBM, Token Ring used a ring architecture to pass datafrom one computer to another. It employs a sophisticated scheme tocontrol the flow of data. If a node needs to transmits data, it must havepossession of a free token before it can create a new token ring dataframe. The token, along with the data frame is sent along as a busytoken.
Fiber Distributed Data Interface ( FDDI)FDDI is a network specification that was produced as a high speed(100Mbps ),token ring network using fiber optic Cables FDDI can
operate as a true ring topology , or it can be physically wired like astar topology.
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Asynchronous Transfer Mode ( ATM )ATM was designed to be a high-speed communication protocol thatdoes not depend on any specific LAN topology. It uses a high-speedcell-switching technology that can handle data as well as real-timevoice and video
Data rates are scalable and start as low as 1.5Mbps and high as155Mbps, but the ideal operating rate is 51.84Mbps.
SONET and SDH are the preferred operating technology in an ATMnetwork topology
Computer Network systems.
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Computer Network systems.
CSMA / CDIn some form, Ethernet has been around for 30 years, a predecessor toEthernet was developed by the university of Hawaii ( calledappropriately the Alohanet ) to connect geographically dispersedcomputers.
This radio-base network operated at 9,600Kbps and used an accessmethod called CSMA/CD ( carrier sense multiple access/collisiondetection ) in which computers listened to the cable and transmitteddata if there was no traffic.
If two computers transmitted data at exactly the same time, the nodesneeded to detect a collision and retransmit the data
Extremely busy CSMA/CD-base networks became very slow whencollisions were excessive.
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Systems Design
Active Devices ( Overview ). Network Interface Card ( NIC )
Hub / Switch
Repeaters / Amp
Bridges
Routers
Gateways
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Systems Design
Network-Connectivity Devices.
Repeaters.A Repeater is a passive electronics device used in a Coaxial network to
regenerate RF and digital signals and send it along in its original state sothat it can be travel farther across a wire.
Hubs.A Hub is a passive electronic device used in a UTP Network toregenerate Ethernet / Digital signals
BridgesJust like a repeater a bridge is a passive network device used to connecttwo network segments. The main difference between them is that thebridge operates at the link layer of the OSI where as the Repeater/Huboperates at the physical layer.
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Switches.A Switches is used in the network to combine all the workstations,phones, and videos on one server . Switches also provide the benefitof micro-LAN segmentation, which means that every node connectedto a Switches port receive its own dedicated bandwidth.
Routers
Routers are packet-forwarding devices just like switches andbridges, however , routers allow transmission of data betweennetwork segments. It operates at the network layer of the OSI
model forwarding packets based on a network ID. Routersforward packets base on there 32 bits IP address.
Systems Design
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Systems Design
Network Interface Card.Network Interface Card or NIC as it is universallyknown is an electronically design Card used to interface
a computer/ Printer with a network or the internet.It has a RJ45 Ethernet jack which is used to connecthigh speed Cables to the Computer ( Cat 5, 5e, 6 )
It replaces the Modem.
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Systems Design
HubBecause repetition of signals is a function of repeating hubs, hubs andrepeaters are used interchangeably when referring to twisted-pairnetworking. The semantic distinction between the two terms is that arepeater joins two backbone coaxial cables whereas a hub joins two ormore twisted-pair cables.
Hubs work the same as repeaters in that incoming signals areregenerated before they are retransmitted across its port. Like repeaters,hubs operate at the OSI physical layer, which means they do not alter orlook at the content of a frame traveling across the wire. When a hub
receives an incoming signal, it regenerates it and sends it out over all itsports.
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Systems Design
SwitchA switch is the next rung up the evolutionary ladder from bridges.In modern star-topology networking, when you need bridgingfunctionality you often buy a switch. Switches also provide the
benefit of micro-LAN segmentation, which means that everynode connected to a switch port receives its own dedicatedbandwidth. Switches operate at the link layers of the OSIreference model and, in the case of layer-3 switches, extend intothe network layer.
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Systems Design
Repeaters
Nowadays the terms repeaters and hubs are used almost in the sameway but they are not the same. Repeaters are used in a coaxial mediumwhere as hubs are used in an Ethernet application.
Repeaters work at the physical layer of the OSI reference model.
Digital signals decay due to attenuation and noise, a repeater job is toregenerate the digital signal and send it along in its original state so thatit can travel farther across a wire.
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Systems Design
Bridges
When we used the terms bridge and bridging, we are generallydescribing functionality provided by modern switches.
A bridge is a network device used to connect two networks segment,the main difference between them is that bridge operate at the link layerof the OSI reference model and can therefore provide translationservice required to connect dissimilar media access architectures suchas Ethernet and Token Ring. In general, there are four types of bridging
Transparent bridging, Source-route bridging, Source-route transparent
bridging, Source-route translation bridging.
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Systems Design
Routers.Routers are packet-forwarding devices just like switches andbridges, however, routers allow transmission of data betweennetwork segments.
Routers operate at the network layer of the OSI reference model,forwarding packets based on a network ID.
How do routers work? In the case of the IP protocol, an IPaddress is 32 bits long. Those 32 bits contain both the network IDand the host ID of a network device.
IP distinguishes between network and host bits by using a subnetmask.
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Systems Design
Routers
The subnet mask is a set of contiguous bits with values of one from left
to right, which IP considers to be the address of a network.
Different types of routable protocol suite
1. TCP/IP - Microsoft
2. IPX/SPXNovell
3. Apple TalkApple Computer.
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Systems Design
The OSI reference model-02.
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Systems Design
As with all other communications protocol, TCP/IPis composed of layers:IP- is responsible for moving packet of data from node to node. IPforwards each packet based on a four byte destination address (the IPnumber). The Internet authorities assign ranges of numbers to different
organizations. The organizations assign groups of their numbers todepartments. IP operates on gateway machines that move data fromdepartment to organization to region and then around the world.
TCP- is responsible for verifying the correct delivery of data from
client to server. Data can be lost in the intermediate network. TCP addssupport to detect errors or lost data and to trigger retransmission untilthe data is correctly and completely received.
Sockets - is a name given to the package of subroutines that provideaccess to TCP/IP on most systems.
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Systems Design
TCP OperationAs noted above, the primary purpose of the TCP is to provide reliable,securable logical circuit or connection service between pairs of processes.To provide this service on top of a less reliable internet communicationsystem requires facilities in the following areas:
Basic Data, Transfer Reliability, Flow Control, MultiplexingConnections, Precedence and Security.
Systems Design
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Systems Design
IP AddressesEach technology has its own convention for transmitting messagesbetween two machines within the same network. On a LAN, messagesare sent between machines by supplying the six byte unique identifier(the "MAC" address). In an SNA network, every machine has Logical
Units with their own network address. DECNET, Appletalk, and NovellIPX all have a scheme for assigning numbers to each local network andto each workstation attached to the network.
On top of these local or vendor specific network addresses, TCP/IPassigns a unique number to every workstation in the world. This "IPnumber" is a four byte value that, by convention, is expressed by
converting each byte into a decimal number (0 to 255) and separatingthe bytes with a period. For example, the PC Lube and Tune server is130.132.59.234.
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Systems Design
Commonly Used TCP/IP ClassesNetwork class Beginning Octet Number of Network Host Addre pernetA 1-126 126 16,777,214B 128-191 >16,000 65,534C 192-223 >2,000,000 254
Class A network share the first octet of their IP addresses, 23.78.110.109,23.164.32.97, 23.56.123.45Class B network share the first two octet of their IP addresses,168.34.88.29, 168.34.55.41, 168.34.73.49Class C network share the first three octet of their IP addresses,
204.139.118.7, 204.139.118.54, 204.139.118.31Because only 126 Class A networks are available on the internet, mostClass A networks have already been reserved by large corporations,educational institutions, or government.127 is not a valid octet for IP addresses, it is used for loopbackinformation.
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Systems Design
Commonly Used TCP/IP Classes
An organization begins by sending electronic mail [email protected] requesting assignment of a network
number. It is still possible for almost anyone to get assignment of a numberfor a small "Class C" network in which the first three bytes identify thenetwork and the last byte identifies the individual computer. The authorfollowed this procedure and was assigned the numbers 192.35.91.* for anetwork of computers at his house. Larger organizations can get a "ClassB" network where the first two bytes identify the network and the last two
bytes identify each of up to 64 thousand individual workstations. Yale'sClass B network is 130.132, so all computers with IP address 130.132.*.*are connected through Yale.