Suppose Host A sends two consecutive TCP segments to Host B over a TCP connection. The first segment has sequence number $29$ ; the second has sequence number $61.$ How much data is in the first segment?

a$.31$ bytes.

b$.32$ bytes.

c$.34$ bytes.

d$.35$ bytes.

e$.59$ bytes.

Host A received a segment through a TCP connection from Host B with sequence number $I532$ and $150$ bytes of data. Then Host A sends one segment with sequence number $1160$ and $70$ bytes of data to Host B$.$ In this same segment the acknowledgment number is:

a$.1681.$

b$.1682.$

c$.1531.$

d$.1532.$

e$.$ None of the above.

A UDP connection is identified by:

a$.$ Source port number and destination port number.

b$.$ Sourec and destination $1P$ addresses and port numbers.

c$.$ Destination port number.

d$.$ Source IP address and destination IP address.

e$.$ None of the above.

The security attack in which the attacker is sending traffic prefending to a destination that does not exist is:

a$.$ Spoofing,

b$.$ Sniffing.

c$.$ DOS.

d$.$ DDos:

e$.$ None of the above.

Layer $3$ of the OSI model is:

a$.$ Presentation.

b$.$ Network.

c$.$ Application.

d$.$ Session.

e$.$ Transport

Which of the following protocols uses TCP$?$

a$.$ OSPF

b$.$ ICMP.

c$.$ RIP.

d$.$ SMTP$.$

e$.$ None of the above.