G.C.E. A/L ICT – Computer Networks Full Summary

INSHAF-0775957722-ICTWITHINSHAF-ADVANCEDLEVEL-M.S.M.INSHAF-0775957722-ICTWITHINSHAF

juTj; njhlu;ghly; vd;gJ ,uz;L my;yJ 02. miu ,Utopg;Nghf;F (Half duplex Mode)
,uz;bw;F Nkw;gl;l njhlu;ghly; rhjdq;fs;
ahNjDNkhu; njhlu;ghly; Clfj;jpid
RECEIVE SEND
gad;gLj;jp juTfis gupkhw;wpf; nfhs;Sk;
nraw;ghlhFk;. SEND RECEIVE
juTj; njhlu;ghlypd; gpujhd $Wfs;
juTfs; ,U jpirfspYk; CLflj;jg;glyhk;
vdpDk; Xu; Fwpj;j Neuj;jpy; xU jpirapy;
khj;jpuNk CLflj;jg;glyhk;.

cjhuzk; : Nthf;fp Nuhf;fp (Walkie-Talkie)

03. KO ,Utopg;Nghf;F (Full duplex Mode)


RECEIVE SEND

1. mDg;Gdu;/%yk; (Sender/Source) SEND RECEIVE
juTfis mDg;Gtjw;fhf gad;gLj;jg;gLk;
fzpdp my;yJ rhjdkhFk;. juTfs; xNu Neuj;jpy; ,U jpirfspYk;
2.ngWdu; (Receiver) CLflj;jg;glyhk;.
mDg;gg;gLk; juTfis ngw;Wf; nfhs;tjw;fhf
cjhuzk; : njhiyNgrp ciuahly;
gad;gLj;jg;gLk; fzpdp my;yJ rhjdkhFk;.
3.njhlu;ghly; Clfk; (Communication Medium rkpf;iQfs; (Signals)
/Transmission System) juTfs; rkpf;iQfshfNt Clflj;jg;gLfpd;wd.
mDg;Gdupy; ,Ue;J ngWdu; tiu juTfs; 01. Analog signal (xg;Gik rkpf;iQ)
nrd;wiltjw;Fupa ghijahFk;.
4. njhlu;ghly; newpKiwfs; (Communication
Protocols)
njhlu;ghlypy; gad;gLfpd;w xU njhFjp
tpjpKiwfshFk;.
5.nra;jp (Message) njhlu;r;rpahd ngWkhdq;fisf; nfhz;L juTfs;
mDg;Gdupy; ,Ue;J ngWdu; tiu nrd;wila tifFwpf;fg;gLk;. ird; miyahf (sine wave)
Ntz;ba juT MFk;. fhzg;gLk;.

juTj; njhlu;ghlypd; tiffs; cjhuzk; : xyp miy> thndhyp miy

01. xw;iw topg;Nghf;F (Simplex Mode) 02. Digital signal (,yf;fKiwr; rkpf;iQ)


SEND RECEIVE

juTfs; vg;NghJk; xU jpirapy; khj;jpuk;
CLflj;jg;gLk;.
cjhuzk; : rhtpg;gyifiag; gad;gLj;jp gpd;dfg; ngWkhdq;fisf; nfhz;L juTfs;
juTfis cs;sply;> njhiyf;fhl;rp kw;Wk; tifFwpf;fg;gLk;. rJu miyahf (square
thndhyp xypgug;G wave) fhzg;gLk;. ,it jdpj;Jtkhd ,uz;L
epiyfis khj;jpuk; gad;gLj;jp (0, 1 – Binary
values) juTfis nfhz;L nry;fpd;wd.



ADVANCED LEVEL ICT 1 0775957722

, INSHAF-0775957722-ICTWITHINSHAF-ADVANCEDLEVEL-M.S.M.INSHAF-0775957722-ICTWITHINSHAF

rkpf;iQfspd; ,ay;Gfs; njhlu;ghly; Clfk; (Transmission Medium)
miyapd; tPr;rk; (Amplitude of wave) 01. topg;gLj;jg;gl;l (Guided) Clfk;
miyapd; cauk; tPrr
; k; vdg;gLk;.
KWf;fpa fk;gpr;Nrhb (Twisted Pair Cable)




miyePsk; (Wavelength)
miy ,af;fj;jpy; gq;Fgw;Wk; xU ,it nrg;Gf; fk;gpfisg;
Jzpf;ifapypUe;J mNjtpaf;f epiyapy; ,Uf;Fk; gad;gLj;jp cUthf;fg;gLk;.
kpff; fpl;ba kw;iwa Jzpf;iff;F cs;s
J}ukhFk;. ,t;tlq;fs; nryT FiwthdJ
kw;Wk; nefpo;Tj;jd;ik
cilaJ.
,lj;Jupg; gug;G (LAN) tiyaikg;Gfspy;
nghJthf ,t;tlq;fNs gad;gLj;jg;gLk;.
xspapay; ehu; tlq;fSld; xg;gpLifapy;
mjpfstpy; neha;jhf;fypw;F cl;gLtJld;
kl;Lg;gLj;jg;gl;l J}uj;jpw;Nf (cau;e;jgl;rkhf
mjpu;ntz;/kPbwd; (Frequency) 100m) rkpf;iQfis nfhz;L nry;Yk;.
xU nrf;fdpy; (XuyF Neuj;jpy;) Mw;wg;gLk;
miyTfspd; vz;zpf;ifahFk;. ,J Hz vDk; ,it ,U tiffspy; fhzg;gLk;.
myfpdhy; msf;fg;gLk;.
1. UTP (Unshielded Twisted Pair Cable)
gupiraplg;glhj KWf;fpa fk;gpr;Nrhb
2. STP (Shielded Twisted Pair Cable)
gupiraplg;gl;l KWf;fpa fk;gpr;Nrhb




mtj;ij/epiy (Phase) – Fwpj;j xU Neuj;jpy;
miy Row;rp Kiwapd; Muk;gpf;Fk; epiyahFk;.

Xur;R tlk; (Coaxial Cable)




,it nrg;Gf; fk;gpfisg; gad;gLj;jp
cUthf;fg;gLk;.


ADVANCED LEVEL ICT 2 0775957722

, INSHAF-0775957722-ICTWITHINSHAF-ADVANCEDLEVEL-M.S.M.INSHAF-0775957722-ICTWITHINSHAF

,t;tlq;fs; nryT FiwthdJ kw;Wk; Ez;ziyfs; (Microwaves)
nefpo;Tj;jd;ik cilaJ.
njhiyf;fhl;rp Antenna kw;Wk; CCTV Nghd;wtw;wp
,t;tlq;fs; gad;gLj;jg;gLfpd;wd.
xspapay; ehu; tlk; (Fiber Optics Cable)




,it Neu;Nfhl;by; gazpf;fj;jf;fJld; mjpf
J}uj;jpw;F juTfis nfhz;L nry;Yk;.
nra;kjpj; njhlu;ghly;fSf;fhf gad;gLk;.
nrq;fPo;f; fjpu;fs; (Infrared Waves)

fz;zhb> gpsh];bf; gad;gLj;jg;gl;L
cUthf;fg;gLk;. ,t;tlq;fspy; juTfs; xspj;
njwpg;ig mbg;gilahff; nfhz;L xsp tbtpy;
Nra;ikf;
gazpf;Fk;.
fl;Lg;gLj;jpfspy;
juTfis mjpf J}uj;jpw;F nfhz;L gad;gLj;jg;gLtJld;
nry;yj;jf;fJld; mjpf Ntfj;jpy; ,it FWfpa J}uj;jpw;Nf
nraw;gLk;. juTfisf; nfhz;L
nry;Yk;.
Vida tlq;fSld; xg;gpLifapy; mjpf
tpiyAilaJ> $upa tisTfis Vw;gLj;j
KbahJ.
topg;gLj;jg;gl;l topg;gLj;jg;glhj
ePz;l J}uj;jpw;F juTfis mDg;Gtjw;f Clfq;fs; Clfq;fs;
,t;tlq;fs; gad;gLj;jg;gLk;. ngsjPfg; ngsjPfg; tlq;fspd;wp
tlq;fspD}lhf juTfs; nfhz;L
02. topg;gLj;jg;glhj (Unguided) Clfk; juTfs; nfhz;L nry;yg;gLk;.
nry;yg;gLk;.
Xg;gPl;lstpy; Xg;gPl;lstpy;
ghJfhg;G mjpfk; ghJfhg;G FiwT
#ow; fhuzpfshy; #ow; fhuzpfshy;
Fiwe;jstpNy mjpfstpy;
ghjpg;gilAk; ghjpg;gilAk;

CLflj;Jif moptiljy; (Transmission
Impairemet)

thndhyp miyfs; (Radio Waves) Clfq;fspD}lhf juTr; rkpf;iQfs; gazpf;Fk;
NghJ mit Kd;du; ,Ue;j epiyapy; ,Ue;J
NtWgLtNj CLfLj;Jif moptiljy; MFk;.

CLfLj;Jif moptiljyhdJ gpd;tUk; 3
tpjq;fspy; Vw;glyhk;.
,it vy;yh jpirfspYk; gutpr; nry;yj;jf;fJ. 1. neha;jhf;fk; (Attenuation)
nry;yplj; njhiyNgrp tiyaikg;Gfs;> 2. jpupG (Distortion)
thndhyp xypgug;G> fk;gpapy;yh 3. ,iur;ry; (Noise)
EZf;Fg;gd;dpfs;> itig> kw;Wk; bluetooth
Nghd;wtw;wpy; gad;gLj;jg;gLfpd;wd.
ADVANCED LEVEL ICT 3 0775957722