Urgent! Need a bit of details for the correct answer. Subject; Distributed Computer Systems

Post by **answerhappygod** » Fri May 20, 2022 10:38 am

Urgent! Need a bit of details for the correct
answer.
Subject; Distributed Computer Systems

: Urgent Need A Bit Of Details For The Correct Answer Subject Distributed Computer Systems 1 (82.34 KiB) Viewed 30 times

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1. A thread differs from a process in that, among other things: (a) It can be created at a lower cost. (b) It provides more data isolation than a process. (c) Switching threads of one process is faster than switching different processes. (d) Communication of threads requires IPC mechanisms. (e) Processes can only be run by a judge. 2. What error/problem occurs in the following code: from threading import Thread, Lock 11 = Lock() 12 = Lock() def thr1(): with 11: with 12: print("Peek-a-boo 1!") def thr2(): with 12: with 11: print("Peek-a-boo 2!") def main(): t1 = Thread(target=thri) t2 = Thread(target=thr2) ti.start() t2.start() if name main() "_main__":

3. What are (among other things) the differences between a binary semaphore and a lock? (a) A semaphore has information about which thread acquired it, while a lock does not. (b) A lock has information about which thread acquired it, while a semaphore does not. (c) A binary semaphore works more efficiently. (d) A semaphore can be used in algorithms where another thread increments and another decrements the semaphore; this is impossible for a lock. (e) A semaphore only occurs at railroad crossings. 4. Among other things, what are the differences between sockets using the TCP and UDP protocols? (a) TCP has a smaller system overhead. (b) UDP ensures that packets are delivered in the correct order, while TCP does not. (c) UDP can be used for multicast transmissions, while TCP cannot. (d) UDP is stateless, while TCP is not. (e) There is no difference: these are the two names for the same protocol. 5. In which application should we consider using UDP, instead of TCP? (a) Video transmission. (b) Transmission of large binary data files. (c) VOIP transmission. (d) Single packet transmission. (e) It is always better to use UDP, because TCP sucks and nobody uses it.

6. What are the advantages of the NFS filesystem? (a) Great scalability on large clusters and supercomputers. (b) Simplicity and high popularity. (c) Dynamic development in the recent years. (d) Security achieved by data replication. (e) NFS has no advantages and nobody uses it. 7. DNS traditionally has been using UDP for: (a) Transferring zone files. (b) Sending requests and responses. (c) Communications using DNSSEC. (d) All transmissions. (e) None of the above. 8. What is the disadvantage of using threads to serve various connections in a server? (a) Relatively hogh system overhead of a thread. (b) Vulnerability to a DDoS attack, by enforcing creation of an outrageous number of threads. (c) The threads do not assure enough data separation. (d) This is forbidden by the law.