A security analyst observes a large number of TCP SYN packets sent to a server, but no SYN-ACK replies are returned. The server is not overwhelmed. Which conclusion is most likely?

The server's TCP stack is misconfigured to ignore SYN packets.

A firewall is dropping the SYN packets before they reach the server.

The client is using UDP instead of TCP.

The server is experiencing a SYN flood and is unable to respond.

What is the primary function of a router in a network?

To assign IP addresses to hosts automatically

To forward packets between different networks based on IP addresses

To amplify and repeat signals on a network segment

To forward frames based on MAC addresses

Which characteristic is unique to TCP compared with UDP?

No acknowledgment of received data

Three-way handshake before data transfer

Lower overhead due to minimal header size

A user reports that typing www.example.com in a browser fails, but typing the IP address 93.184.216.34 works. Which step in the name resolution process is most likely failing?

The TCP handshake to port 80 on the web server

The DNS query to resolve www.example.com to an IP address

The ARP request for the default gateway

The HTTP request to the web server

GIAC Information Security Fundamentals

Domain 2Objective 1

Foundations of Network Communication GISF Practice Questions (Page 10)

Part of the Network and Systems Security domain, which makes up ~28% of our current practice bank. GIAC (SANS) does not publish an official question count, but from its 120-minute exam (~50–80 total, ~14–22 in this domain), expect 5–7 from this objective — we provide 53 practice questions to prepare you well beyond it. (estimate)

53questions here

11free pages

11concepts

Questions 46–50

46expert · hard
A security analyst observes a large number of TCP SYN packets sent to a server, but no SYN-ACK replies are returned. The server is not overwhelmed. Which conclusion is most likely?
Select an answer first
47application · medium
A security analyst is troubleshooting a VoIP call quality issue. The call setup uses SIP over TCP, but the RTP media stream is experiencing jitter and dropped packets. The analyst notices that the RTP packets are being fragmented. Which protocol and port combination should the analyst verify is being used for the media stream?
Select an answer first
48foundation · easy
What is the primary function of a router in a network?
Select an answer first
49foundation · easy
Which characteristic is unique to TCP compared with UDP?
Select an answer first
50application · medium
A user reports that typing www.example.com in a browser fails, but typing the IP address 93.184.216.34 works. Which step in the name resolution process is most likely failing?
Select an answer first

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