38, ASPF is an application-layer packet filtering technology that implements special security mechanisms based on the server mapping table. Which of the following statements about ASPF and server mapping tables are true? A. ASPF monitors communication packets. B. ASPF can dynamically create a server mapping table. C. 5-tuple server mapping entries have similar functions to session entries. D. ASPF uses the server mapping table to dynamically allow multi-channel protocol packets to pass through.

38, ASPF is an application-layer packet filtering technology that implements special security mechanisms based on the server mapping table. Which of the following statements about ASPF and server mapping tables are true? A. ASPF monitors communication packets. B. ASPF can dynamically create a server mapping table. C. 5-tuple server mapping entries have similar functions to session entries. D. ASPF uses the server mapping table to dynamically allow multi-channel protocol packets to pass through.

Comptia A+ Core 1 Exam: Guide To Computing Infrastructure (mindtap Course List)

10th Edition

ISBN:9780357108376

Author:Jean Andrews, Joy Dark, Jill West

Publisher:Jean Andrews, Joy Dark, Jill West

Chapter8: Network Infrastructure And Troubleshooting

Section: Chapter Questions

Problem 8TC

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In order to implement a DNS amplification attack, the attacker must trigger the creation of a sufficiently large volume of DNS response packets from the intermediary to exceed the capacity of the link to the target organization. Consider an attack where the DNS response packets are 500 bytes in size (ignoring framing overhead). a. How many of these packets per second must the attacker trigger to flood a target organization using a 30-Mbps link? A 100-Mbps link? Or a 1-Gbps link? b. If the DNS request packet to the intermediary is 60 bytes in size, how much bandwidth does the attacker consume to send the necessary rate of DNS request packets for each of these three cases?
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2. Suppose a large file of size F bits is to be sent from host A to host B. There are two links and two routers on the path from A to B. The links are uncongested and the link propagation delays are negligible. Host A segments the file into segments of size S bits each and adds 60 bits of header to each segment, forming packets of size L = S+ 60 bits. Each link has a transmission rate of R bps. Find the value of S that minimizes the file transfer delay from host A to host B.
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Consider a simple UDP-based protocol for requesting files (based somewhat loosely on the Trivial File Transport Protocol, or TFTP). The client sends an initial file request, and the server answers (if the file can be sent) with the first data packet. Client and server then continue with a stop-and-wait transmission mechanism. (a) Describe a scenario by which a client might request one file but get another; you may allow the client application to exit abruptly and be restarted with the same port. (b) Propose a change in the protocol that will make this situation much less likely.