कौन सा पैकेट स्विच्ड WAN नहीं है?
Which is not a packet switched WAN ?
A
ATM
B
ISDN
C
Frame Replay
D
X.25
Explanation
The correct answer is:
(B) ISDN
ISDN (Integrated Services Digital Network) is a circuit-switched network, not a packet-switched WAN. The other options, ATM (Asynchronous Transfer Mode), Frame Relay, and X.25, are all packet-switched WAN technologies.
Correct Answer: B) ISDN
