Tcp Ip - Study Mode

[#1] Which of the following is the decimal and hexadecimal equivalents of the binary number 10011101?
Correct Answer

(B) 157, 0x9D

Explanation

Solution: To turn a binary number into decimal, you just have to add the values of each bit that is a 1. The values of 10011101 are 128, 16, 8, 4, and 1. 128 + 16 + 8 + 4 + 1 = 157. Hexadecimal is a base-16 number system. The values of hexadecimal are 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, A, B, C, D, E, F-16 characters total, from which to create all the numbers you'll ever need. So, if 1001 in binary is 9, then the hexadecimal equivalent is 9. Since we then have 1101, which is 13 in binary, the hexadecimal answer is D and the complete hexadecimal answer is 0x9D.

[#2] Which statements are true regarding ICMP packets? 1. They acknowledge receipt of a TCP segment. 2. They guarantee datagram delivery. 3. They can provide hosts with information about network problems. 4. They are encapsulated within IP datagrams.
Correct Answer

(C) 3 and 4

Explanation

Solution: Internet Control Message Protocol (ICMP) is used to send error messages through the network, but they do not work alone. Every segment or ICMP payload must be encapsulated within an IP datagram (or packet).

[#3] Which layer 4 protocol is used for a Telnet connection?
Correct Answer

(B) TCP

Explanation

Solution: Although Telnet does use TCP and IP (TCP/IP), the question specifically asks about layer 4, and IP works at layer 3. Telnet uses TCP at layer 4.

[#4] Which statements are true regarding ICMP packets? 1. ICMP guarantees datagram delivery. 2. ICMP can provide hosts with information about network problems. 3. ICMP is encapsulated within IP datagrams. 4. ICMP is encapsulated within UDP datagrams.
Correct Answer

(B) 2 and 3

Explanation

Solution: ICMP is used for diagnostics and destination unreachable messages. ICMP is encapsulated within IP datagrams, and because it is used for diagnostics, it will provide hosts with information about network problems.

[#5] Which of the following are TCP/IP protocols used at the Application layer of the OSI model? 1. IP 2. TCP 3. Telnet 4. FTP 5. TFTP
Correct Answer

(C) 3, 4 and 5

Explanation

Solution: Telnet, File Transfer Protocol (FTP), and Trivial FTP (TFTP) are all Application layer protocols. IP is a Network layer protocol. Transmission Control Protocol (TCP) is a Transport layer protocol.