● (71) is a one-way function that takes an arbitrarily long piece of plaintext and from it computes a fixed-length bit string．(72) is a protocol that most USENET machines now use it to allow news articles to propagate from one machine to another over a reliable connection．(73) is an approach preferred by cable TV providers ．In this solution the fiber terminates at an optoelectrical converter and the final segment is a shared coaxial cablE.(74) is a device used to connect two separate network that use different communication protocol．(75) is a digital-to-digital polar encoding method in which the signal level is always either positive or negativE.(71) A.MDB.RSAC.DESD.MIB(72)A.RTPB.RTTPC FTPD.NNTP(73) A.ADSLB.FTTCC.HFCD.FTTH(74)A ．RouterB.GatewayC.BridgeD.hub(75)A ．NNIB.NRZC.NAKD.NVT
A.B.
C.In
D.
E.
F.
(71)
G.RSA
H.DES
I.MIB
J.RTP
K.RTTPC
L.NNTP
M.FTTC
N.HFC
O.FTTH
P.Router
Q.Gateway
R.Bridge
S.hub
T.NNI
U.NRZ
V.NAK