pesanan buat mu

Sewaktu kau melangkah pergi
Meninggalkan diri ku
Sebaknya rasa di dalam dada ku
Menahan titis airmata
Ingin aku berpesan
Kepada mu kekasih
Sekiranya engkau merindui diri ku
Hubungilah aku di sini
* :
Jika ada kesilapan ku
Maafkanlah diri ku oh sayang
Dan izinkanlah aku bertanya
Mengapa kau berubah hati
** :
Kiranya kau ada pengganti ku
Tetapi hidup mu tak bahagia
Rela aku memaafkan mu
Dan aku menrima mu sayang
Walaupun hati ku kau lukai
Namun ku masih menyayangi mu
Kerana sehingga waktu ini
Cinta ku masih untuk mu
*** :
Oh sayang di manakah kau berada
Janganlah kau lupakan aku
Ingat aku walau sesaat
Seorang insan yang terluka
Ingin aku berpesan
Kepada mu kekasih
Kiranya kau resah dan tak lena
Itulah hembusan rindu ku
( Ulang Rangkap *, ** dan *** )

 sesungguhnya ALLAH saja yang tahu apa yg tersirat dalam hati ni
yela,,walaupun orang lain dok kata 'xpa,,ak phm..'
yes!i knw you all faham!tp aku yg rasa semua tuh!
tp sampai bila??
sampai bila2 ke aku kena rasa semua tuh?
thanks dan TAHNIAH laa sebab main kn perasaan orang..

mrs. R

wink2!

wihuu...lame nye rase xupdate blog!huhu

update pon sebab lecturer yg suruh..kalo x, blog nih mmg xwujud laa kn..ngee

btw, alhamdulillah sebab masih lagi bernafas di muka bumi ini..hehe

ya ALLAH,, mcm2 dugaan perkara yang berlaku dalam sem nih..

mana nk catch up study lg, masalah peribadi yang xprnh settle, n yang paling penting ttg MAK sy!

1st, sem nih nye subjek mmg gler2 tough!

jadual pack k0t!xpnh2 ad cls ptg,,sem nih boleh plak ad clss ptg,,huhu,,mmg ngantok laa jawab nye..hehe

rasenye jasad je yg ad dlm cls tuh,,tp hati n otak xpnh ad dlm clss..haha (mana nk focus stdy) ngeh3..

2nd, masalah peribadi..hmmm,,ssh laa nk gambar kn mcm mana perasaan nye.. Allah jela yang tahu..

masalah xkn settle kal0 semua pihak xnk mngalah ngn EGO mereka sendiri..

hey!!kire ok laa kite nih lembut hati TURUN kn ego,,kal0 x, mmg xke mana la kn.

3rd, MAK saya :(

dia sakit yg xtaw pe punca nye..mule2 d0lu sakit pinggang, then nk buang air kencing xlawas. n n0w d0c kata dy skit tulang plak!ape kes!!!

mane 1 nih..len d0c, len pendapat, n len penyakit yang mereka level kn kt MAK saya tuh..haihh..xleh jd nih,,

lately nih, mak slal0 skit n dy xleh nk tahan skitnye tuh.. cian neg0k sy smpai nanges2 tahan sakit!

tp 0n that time, sy xda laa tunjuk kt mak yang sama pon turut nk nanges..huhu,..sdh k0t!

smoga mak cpt sembuh!

n thanks kt kwn2 yg caring psl sy n slalo tye ttg kshtn mak sy tuh..huhu..alhamdulillah,,

nih laa nama nye KAWAN!!!mereka ad waktu susah dan senang..

ad je org nk berkawan dgn kita waktu sng!tp waktu ssh,,msing2 wt xtaw ja..s0keyh..sy xd0akn pape..tggu jela KARMA dari ALLAH!

sm0ga anda BAHAGIA ngn hidup anda tuh..

wt jahat ngn orang xkn kemana laa weyh!

final dah nk dkt nih..wish me all the best!hehehe.. <3

may ALLAH bless all of you.. wink2! :)

-wassalam-

mrs. R

internet infrastructure

• internet is a global network connecting millions of computer using a common set of communication protocols called TCP/IP.
• a hierarchy of networks:
• single c0mputer => LAN => ISP => WWW
• to connect with the internet, we need:
• computer
• web browser
• internet access

INTERNET PROTOCOL (IP)

• provides a common layer over dissimilar networks
• used to move packets among 'host' computers and through gateways
• IP add consist of 32 bit ( 4 octets of number from 0-255 represented in decimal form instead of binary form).
• IP add ==> 168.212.226.204
• binary form ==> 10101000.11010100.11100010.11001100
• IP add consist of 2 part:
• identifying the network
• identifying the node/host

CLASS A NETWORK

• binary add start with 0
• decimal number can be anywhere from 1 t0 126
• the 1st 8 bits (1st 0ctet) identify the network and the remaining 24 bits indicate the host within the network.
• example:  102.168.212.226
•  102 ==> identify the network

wireless (unb0unded media/unguided media)

• media transport electromagnetic wave without physical conductor.
• signal broadcasting through air or water.
• divided by 3 types:
• terrestrial microwave
• horn
• satellite

TERRESTRIAL MICROWAVE

• require line-of-sight transmission and reception equipment.
• the taller the antennas, the l0nger the sight distance.
• t0wer: 0n hills/m0untins
• signal transmit 0ne way direction at a time
• t0 increase the distance, repeater can be installed with antenna
• 2 types 0f antennas:
• parab0lic dish
• h0rn

PARABOLIC DISH

• parabola
• works like a funnel

HORN

• gigantic scoop
• 0utg0ing transmissi0n are br0adcast up a stem and deflected 0utward in a series 0f narr0w PARALLEL BEAMS by the scooped shape of the horn

SATELLITE

• same principle as terrestrial microwave
• acting ad a super tall antenna and repeater
• single b0unce
• capability is any l0cati0n an earth n0 matter h0w rem0te
• high qualityc0mmunicati0n without requiring a huge investment in gr0und-based infratructure
• same speed = earth
• geosynchronous satellite = orbit speed is based on distance from the planet
• minimum 3 satellite t0 pr0vide full gl0bal transmissi0n
• uplink = transmission from earth to satellite
• d0wnlink = transmission from the satellite to earth

WI-FI

• transmits computer data over distance
• using radio waves
• system follow a standard : 802.11
• create by the institute Electrical and Electronics Engineers (IEEE)
• the system use a license-exempt portion of the radio spectrum
• anyone can set up a WI-FI netw0rk without applying a license or pay for broadcasting rights 

• divided by 2:
• 802.11 a  =  all0w transmits data 0f 54 Mbps
• operating in the 5GHz frequency range
• 802.11 b =  all0w transmits data 0f 11 Mbps
• operating in the 2.4 GHz frequency range
• range = 100-1000 feet

equipment need to set up WI-FI LAN

• WI-FI compatible radio (Wi-Fi card / 802.11b card)
• types of card:
• PC card
• a standard Type II PC Card that slide int0 your laptop's PC Card slot.
• knowns as PCMCIA (Personal Computer Memory Card International Association)
• the protruding end contains a bulit-in antenna - miniature twin diversity antenna (improve coverage)
• USB Adapters
• als0 kn0wn as PCI/ISA bus adapter
• PCI anf ISA Bus Adapters
• these can ne either one-pieces ISA or PCI radios or tw0-piece units that cmoprise a PC Card reader od adapter and a separate Wi-Fi PC Card Radio the slides into the reader.
• compact Flash and other Small-CLient Formats
• designed for smaller PDAs and other mobile computing device
• 802.11b/ Wi-Fi radios can be built onto a Compact Flash format

Advantages of Wi-Fi

• mobility
• reliability
• ease of installation
• afforting scalability

Radio Frequency

• rate of oscillation in the rangr of about 3 kHz to 300 GHz.
• corresponds to the frequenct of radio waves
• alternating currents which carry radio signals
• refer to electrical rather than mechanical oscillations.
• equipment:
• Short Range Devices (SRD), 
• Bluetooth And WLAN (802.11a/b/g/n),
• base stations,
• repeaters,
• 2G/3G/LTE mobile phones,
• PMR radio

Cellular Phones

• kn0wn as mobile phone, cell phone, hand phone.
• device can make and receive telephone cell over a radio link whilst moving around a wide geigraphic area.
• a cordless telephone is used only within the short range of a single, private base station.
• support a wide variety of other services
• text messaging, MMS, email, internet access and s0 0n.

Uplink

• portion of a communication link used for the transmission of signals
• from Earth terminal to Satellite/airborne plateform.
• inverse of a downlink.
• pertaining to GMS and cellulat network.
• the transmission path from the mobile station(cell phone) tp a base station(cell site)
• traffic ang signalling flows within the BSS and NSS
• pertaining to computer network
• connection from data communications equipment  toward the network core
• known as an upstream connection

Downlink

• link from a satellite to a ground station.
• pertaining to cellular network
• transmission path from a cell site to the cell phone.
• traffic and signalling flows within the base station subsystem (BSS) and network switching subsystem (NSS).
• pertaining to a computer networks
• connection from data communications equipment towards data terminal equipment 
• known as downstream connection.

cabling

cable is the medium through which information usually moves from one network device to another.
LANs is the type of several types of cable are commonly used.
there are 5 types of cables, which is:

• Unsheilded Twisted Pair (UTP) cable
• Sheilded Twisted Pair (STP) cable
• Coaxial cable
• Fibre Optic cable
• Wireless LANs

usually, UTP, STP and Coaxial Cable are transmitted with the electric. but, Fibre Optic Cable and Wireless LANs are transmitted by light.

Unsheilded Twisted Pair (UTP) cable

• 4 pairs of wires inside the jacket
• each pair is twisted with a different number of twisted per inch

• 5 categories:
• category 1 : voice ( telephone wire)
• category 2 : data to 4Mbps (local talk)
• category 3 : data to 10Mbps (ethernet)
• category 4 : data to 20Mbps (16Mbps token ring)
• category 5 : data to 100Mbps (fast ethernet)
• standard connector is an RJ-45 connector

• disadvantage of UTP : may be susceptible to radio and electrical frequency interference

Sheilded Twisted Pair (STP) cable

• consist of tw0 individual wires wrapper in a foil shielding-help provide a more realiable data communication
• suitable for environments with electrical interference.
• extra shielding can make the cables quite bulky

Coaxial cable

• has a single copper conductor at its center
• a plastic layer provides insulation between the center conductor and a braided metal shield
• the metal shield helps to block any outside interference from fluorescent lights,motors, and other computers.

• coaxial cable connector:
• Bayone-Neill-Concelman (BNC) connector
• different types of adapters are available for BNC connectors, including:
• T-connector
• barrel connector
• terminator

Fibre Optic

• consists of a center glass core surrounded
• transmits lightrather than electronic signals eliminating the problem of electrical interference.
• large amount of electrical interference
• able to transmit signals over much longer distances than coaxial and twisted pair.

week 6: NETWORK TOPOLOGY

network t0p0l0gy is an arrangement, mapping 0f the element like a links and n0des. netw0rk t0p0l0gy asl0 kn0wn as lay0ut 0r design. netw0rk t0p0l0gy may be physical 0r l0gical.

• physical t0p0l0gy refers t0 the physical design 0f a netw0rk including the devices, l0cati0n and cable installati0n.
• linear bus, star, star wired ring, tree

• l0gical t0p0l0gy refers t0 h0w data is actually transferred in a betw0rk as 0pp0sed t0 its phusical design.
• like a s0ftware

= > physical t0p0l0gy relates t0 a c0re netw0rk whereas l0g0cal t0p0l0gy relates t0 basic netw0rk.

• n0des is a c0mputer that relate the devices.

LINEAR BUS

• c0nsists 0f a c0ntinu0us length 0f cable that c0nnects tw0 0r m0re device t0gether.
• a bus called a backb0ne netw0rk.

• 0n the bus netw0rk, 0nly 0ne c0mputer can transfer inf0rmati0ns at a time.
• the inf0rmati0ns m0ves thr0ugh the entire length 0f the cable.
• each end 0f the cable 0n the bus netw0rk must have a TERMINAT0R.
• terminat0r are a device that abs0rb the signals transmitted 0n a netw0rk cable.

THE ADVANTAGES 0F LINEAR BUS

• easy t0 c0nnect
• require less cable
• setup  0f a bus netw0rk is simple.
• 0ften used t0 c0nnect a few c0mputers l0cated in a small area, such as an 0ffice.

THE DISADVANTAGE 0F LINEAR BUS

• when adding a c0mputers t0 a bus netw0rk, the cable must be br0ken t0 extend the cable and attach the c0mputer.
• the 0ther c0mputer 0n the netw0rk cann0t exchange inf0rmati0n whike the cable is br0ken.
• if 0ne 0f the device is br0ken, the wh0le device will be br0ken.
• large bulding d0es n0t used linear bus.

STAR NETW0RK 

• c0nsists 0f individual c0mputer c0nnected t0 a centre p0int 0n the netw0rk

• each c0mputer is c0nnected t0 a central netw0rk c0nnect0r, called a hub.
• the inf0rmati0n that transfer fr0m 0ne c0mputer t0 an0ther 0n the netw0rk passed thr0ugh the hub.
• each c0mputer must be relatively cl0se t0 the netw0rk hub.
• cable length between a c0mputers and the hub sh0uld be less than 100 meters.
• hubs c0mm0nly c0nnect 4, 8, 0r 16 c0mputers t0gether.
• it is g0od t0 used at large bulding.

THE ADVANTAGES 0F STAR NETW0RK

• easy detect fault
• easy t0 add new w0rkstati0n
• easy t0 install & wire
• the netw0rk d0es n0t need t0 be shut d0wn when new c0mputers are c0nnected

THE DISADVANTAGES 0F STAR NETW0RK

• if 0ne hub is br0ken, the wh0le n0des are br0ken t0o.
• large am0unts 0f cable are used.
• each c0mputer must be c0nnecting t0 a netw0rk hub, an expensive c0mp0nent

TREE NETW0RK

• c0mbinati0n 0f linear bus and star netw0rk

NIC (NETW0RK INTERFACE C0NTR0LLER)

• c0mputer hardware c0mp0nent that c0nnects a c0mputer t0 a c0mputer netw0rk.
• c0mm0nly implemeted 0n expensive cards that plug int0 a c0mputer bus

NOS (NETWORK OPERATING SYSTEM)

• reffered t0 as th Dial0guer; is the s0ftware that runs 0n a server and enables the server t0 manage data, users, gr0ups, security, applicati0ns and 0ther netw0rking functi0ns.
• design t0 all0w shared file and printer access among multiple c0mputers in a netw0rk, typically a l0cal area netw0rk (LAN), a private netw0rk 0r t0 0ther netw0rk.
• the m0st p0pular NOS are Microsoft Windows Server 2003.

REPEATER

• an electr0nic devices that receive a signal and transmits it at a higher level 0r higher p0wer, 0r 0nt0 the 0ther side 0f an 0bstructi0n, s0 that the signal can c0ver l0nger distances.
• the functi0n is:
• t0 receive a netw0rk signal f0rm 0ne LAN terminal cable segment and t0 regenerate and retransmit the signal as it is in its 0riginal strength 0ver a  0ne 0r m0re 0ther cable segment.
• regenerates the strength 0f the signal bef0re transmitting

NETW0RK SWITCHES

• c0mputer netw0rking device that c0nnects netw0rk segments 0r netw0rk devices.
• the term c0mm0nly refer t0 a multiple-p0rt netw0rk bridge that pr0cesses and r0utes data at the data link layer.

C0NCENTRAT0R

• pr0vide c0mmunicati0n capability between many l0w-speed, usually asynchr0n0us channels and 0ne 0r m0re high-speed, usually synchr0n0us channels.
• a device that c0nnects a number 0f links with 0nly 0ne destinati0n
• the main functi0n is t0 make a kink 0f l0ad balancing between tw0 0r m0re servers c0nnected t0gether, data distributi0n is d0ne acc0rding t0 the server pr0cessing rate.

ETHERNET

• has largely replaced c0mpeting wired LAN techn0l0gies.
• devude a stream 0f data int0 individual packets called FRAMES
• each frame c0ntains s0urce and destinati0n addresses and err0r-checking data; damaged data can be detected and re-transmitted.
• used c0axial cable as a shared medium.
• later the c0axial cables were replaced by twisted pair and fibre optic links in c0njuncti0n with hubs 0r switches.

L0CAL TALK

• a system 0f shielded twisted pair cabling, plugged int0 self-terminating transceivers, running at a rate 0f 230.4 kbit/s.
• its sl0s. at 230.4 kbit/s, its faster than a m0dem, but at 1 MB/min, it takes f0rever t0 m0ve large files 0r d0 backup 0ver the netw0rk.
• it gets c0ngested. all inf0rmati0n is br0adcast t0 the entire netw0rk, s0 a few heavy userd can bring it t0 its knees. the m0re users, the w0rse it gets.
• its a daisy chain f0rm 0ne device t0 the next t0 the next. if the wiring g0es bad, y0u end up with tw0 netw0rks that can't talk with each 0ther.

T0KEN RING

• l0cal area netw0rk pr0t0c0l which resides at the data link layer (DLL) 0f the OSI m0del.
• it uses a special three-byte frame called a t0ken that travels ar0und the ring.
• t0ken-p0ssessi0n grants the p0ssess0r permiti0n t0 trasmit 0n the m0dem.
• t0ken ring frames travel c0mpletely ar0und the l0op.

week 5: c0mputer netw0rking

C0mputer netw0rking is the c0nnecti0n with 0ne t0 ant0her c0mputer t0 enable them c0mmunicate each 0ther. C0mputer netw0rk als0 as the way t0 share hardware, s0ftware and data as well as t0 c0mmunicate with 0ne an0ther. There are a few 0f netw0rk classificati0n which is LAN, WAN, MAN, PAN and s0 0n.

LAN is sh0rt f0rm fr0m L0cal Area Network. It is work as a c0vers relatively small g0egraphical such as in a h0me, sch0ol and 0ffice area.

WAN is Wide Area Netw0rk were covers large ge0graphical area. It consist 0f tw0 0r m0re LAN c0nnected t0gether using c0mmunicati0ns techn0l0gy internet is the largest WAN.

MAN is Metr0p0litan Area Networks. The netw0rk design t0 service a metr0p0litan area like a city. It was c0nsist 0f multiple LAN and the size is between LAN and WAN.

PAN is a Pers0nal Area Netw0rk. It is w0rked as a pers0nal device like printer, m0bile devices and s0 0n. The way netw0rk are w0rking is thr0ugh wired 0r wireless.

0n the netw0rking, there are have s0me c0mp0nents t0 make c0mputer w0rk as well. The c0mp0nents can be categ0ries:

1. Terminals, w0rkstati0ns, c0mputer and 0ther devices (end c0de)

1. Data s0urces and destinati0ns
2. Example is pers0nal c0mputer, terminal, w0rkstati0ns, c0mputers and aut0matic teller machines.

2. transmissi0n Media (f0r transmitting data and c0ntr0l signals)

1. Transmit data in a netw0rked envir0nment.
2. Divided by 2 types

                   i.      B0unded/guided: twisted pair, c0axial, fibre 0ptics

                   ii.      Unb0unded/unguided (air/vacuum): satellite c0mmunicati0n, micr0wave radi0, infrared signals

3. s0ftware t0 c0ntr0l data transmissi0n

1. Inf0rmati0n, data 0r pr0gramming used-c0mmunicate/c0nnect t0 0ne and an0ther.
2. share inf0rmati0n

4. netw0rk electr0nics (intermediate devices f0r r0uting data fr0m s0urce t0 destinati0n)

1. Act as interface between different transmissi0n media/c0mmunicati0n pr0t0c0l
2. Example: hub, r0uter,switch, bridge, gateway.

• HUB :
•  device f0r c0nnecting multiple internet device t0gether and making them act as a single netw0rk segment.
• has multuple input/0utput p0rts
• w0rks at the physical layer 0f the OSI m0del

• ROUTING
• pr0cess 0f selecting paths in a netw0rking al0ng which t0 send netw0rk traffic.
• perf0rmed at teleph0ne netw0rk (circuit switching), electr0nic data netw0rks and transp0rtati0n netw0rks.
• the functi0n :
• manage the part al0ng which inf0rmati0n is f0rwarded within a netw0rk; facilitate c0mmunicati0n between c0mputers and internet.
• c0me in tw0 types: dynamic and static.
• dynamic is manage data traffic acr0ss the netw0rk; manage by r0uting pr0t0c0l.
• static is manuaaly c0nfigured by a netw0rk administrat0r wh0 pr0grams all 0f the necessary r0utes that are needed f0r data packets.

• GATEWAY
• called pr0t0c0l c0nverters, 0perate at any netw0rk layer.
• essential feature 0f m0st r0uters, alth0ugh 0ther devices can functi0n as a gateway

• BRIDGE
• device that f0ll0w the c0mputers 0n individual netw0rks 0r separate parts 0f a netw0rk t0 exchange inf0rmati0n.
• used t0 c0nnect a sma;; number 0f individual netw0rks t0 w0rk t0gether as 0ne large netw0rk.
• split an 0verl0ad netw0rk int0 small parts

• PRIVATE BRANCH EXCHANGE (PBX)
• swicth stati0n f0r teleph0ne systems
• c0nsists mainly 0f several branches 0f teleph0ne systems and its swicth c0nnecti0ns t0 and fr0m them.
• the functi0n:
• pr0vide 0ne single number taht external callers can use t0 access all pers0ns in a c0mpany
• distribute calls t0 empl0yerd in a answering team in an even way; using the Aut0mate Call Distributi0n (ACD) feature.
• all0w the user 0f cust0mized business greetings.
• pr0vide system call management features.
• transfer calls between internal extensi0n.

• BLUETOOTH VS INFRARED
• bluet0oth:
• wireless and aut0matic and 0ffers users with variaties 0f excellent features that has recreated the art 0f c0nnecti0n
• bluet0oth techn0l0gy w0rks by transmitting signals via l0w frequency radi0 signa
• the part 0f  c0mmunicati0n is appr0ximately w0rking 0n 2.45 gigahertz.
• the standard range is ar0und ten meters
• many  ways have c0ntributed much in c0nnecting individual systems with0ut being b0thered by bulk 0f the cables and wires.
• 
  
• infrared:
• 0ne t0 0ne pr0cess
• transmit  signals between the tw0 but n0t with an0ther separate system.
• w0rks 0nly 0n the line 0f sight principle where in 0ne has t0 p0int th infrared device directly t0 the h0st system t0 achive a desirable result.

• FM (Frequency M0dulati0n) radi0
• c0nvey inf0rmati0n 0ver a carrier wave by varying its instantane9us frequency.
• carry a stere0 signals
• used at ZHF radi0 frequencies f0r h9gh-firelity br0adcasts 0f music and speech
• frequency is varied, and phase m0dulati0n, in which the phase is varied.

• AM (Amplittude M0dulati0n)

• technique used in electr0nic c0mmunicati0n, m0st c0mm0nly f0r transmitting inf0rmati0n v0a radi0 carrier wave.
• w0rks by varying the strength 0f the transmitted signals in relati0n t0 th inf0rmati0n being sent.
• f0r example, change in signal strength may be used t0 specific the s0unds t0 be repr0duced by a l0udspeaker, 0r the light intnsity 0f televisi0n pixels.