You have been assigned the /24 network and need to segment it into at least 60 subnets. Which network mask meets this requirement?（）

单项选择题Which network mask is the equivalent of 255.255.248.0?（）

A. /20
B. /21
C. /22
D. /23

多项选择题Which two protocols use UDP as a transport protocol by default?（）

A. Telnet
B. ICMP
C. DHCP
D. RIP

多项选择题Which three protocols use UDP as a transport protocol by default?（）

A. HTTP
B. TFTP
C. DNS
D. SNMP
E. SMTP

多项选择题You have been asked to develop an application that uses only connection-oriented protocols. Which two protocols can you use?（）

A. PPP
B. UDP
C. TCP
D. ICMP

多项选择题Which two characteristics describe the UDP protocol?（）

A. limited error checking
B. defined timers
C. no recovery mechanisms
D. three-way handshake