Catalyst switches utilize a special technology to identify and prevent topology loops and ensure that data flows properly through a single network path. What is the name of this technology?（）

多项选择题Which fields are included in the TCP header?（）

A. Source Port
B. Acknowledgement Number
C. Request Number
D. Destination Address
E. Window
F. Data

单项选择题How many simultaneous Telnet sessions does a Cisco router support by default?（）

A.1
B.2
C.3
D.4
E.5
F.6

单项选择题Which of the following protocols use both TCP and UDP ports?（）

A. FTP
B. SMTP
C. Telnet
D. DNS
E. All of the above

多项选择题What statements are true regarding ICMP packets?（）

A. They acknowledge receipt of TCP segments.
B. They guarantee datagram delivery.
C. They can provide hosts with information about network problems.
D. They are encapsulated within IP datagrams.
E. They are encapsulated within UDP datagrams.

多项选择题Which three address ranges are used for internal private address blocks as defined by RFC 1918?（）

A. 0.0.0.0 to 255.255.255
B. 10.0.0.0 to 10.255.255.255
C. 172.16.0.0 to 172.16.255.255
D. 172.16.0.0 to 172.31.255.255
E. 127.0.0.0. to 127.255.255.255
F. 192.168.0.0 to 192.168.255.255
G. 224.0.0.0 to 239.255.255.255