CCNA Network Essentials Answers

1.     48 bits and represented by 6pairs of hexadecimal digits.

2.     RJ-45

3.     Unshielded Twisted Pair

4.     Star

5.     One, 12

6.     Application, Presentation, Session, Transport, Network, Datalink, Physical

7.     Application layer

8.     Transport – Segment, Network – Packet / Datagram, Datalink – Frame, Physical – Bit

9.     Layer 3, Network layer

10.  Connection-oriented eg. TCP is a connection-oriented protocol that uses acknowledgement (overhead)

11.  Modem

12.  DNS

13.  0 to 1023

14.  LLC (logical link control) & MAC (media access control)

15.  ARP

16.  Physical Layer

17.  Data Link layer

18.  Physical Layer

19.  Data link layer

20.  Presentation layer

21.  Internet Control Message Protocol, a network layer protocol used by network devices to send error notification

22.  UDP

23.  ICMP echo request & echo reply. PING - Packet Internet Groper

24.  Ethernet with maximum transfer rate of 100 Mbps, uses baseband signalling and Twisted pair cabling

25.  FTP uses TCP & TFTP uses UDP. Authentication is mandatory in FTP, not in TFTP

26.  TCP: Connection oriented protocol, Reliable (uses acknowledgement), supports error correction, comparatively slow.

UDP: Connection less protocol, Unreliable (no acknowledgement), supports error detection, faster than TCP

27.  DNS - 53 ; Telnet - 23 ; SMTP – 25 ; POP3 - 110

28.  FTP Data channel Port no : 21, Control channel : 20

29.  CSMA/CD

30.  Optic Fibre

31.  Leased Line

32.  Core, Distribution & Access

33.  Any packet switched (or Cell Switched) PVC eg. X.25, Frame Relay, ATM

34.  DTE – Data Terminal Equipment ; DCE – Data Circuit Terminating Equipment

35.  CSU/DSU – Channel Service Unit / Data Service Unit (or Digital Service Unit)