hould be free from plagiarism and should not be uploaded on course hero. because last time it was uploaded and all my friend copied from there and i got zero because of similarity.

the references along with citation is must required.

 

Computer networksIt should be 6 typed pages. References with citaTon is must required.±otal: 10 pointsASSIGNMEN± ±ASKS±ask 1 (4 marks) Both the CSMA/CD with ±oken bus medium access control methods can be used in realTme systems. Which one is be²er suited for real Tme applicaTons? Explain.±ask 2 (6 marks) Suppose you want to build a home network that includes a router with an ADSLconnecTon to the Internet, a wireless IEEE802 Wireless LAN, and three wireless IEEE802 Wireless LANadaptors. Find speci³c products to suit your needs and price them out.±ask 3 (4 marks) brie´y describe a²acks against security and discuss three desirable properTes of securecommunicaTon.±ask 4 (5 marks) suppose that N people wish to communicate with each other using a shared medium,i.e., all transmissions can be read by all parTcipants. CommunicaTon between any two parTcipants mustbe kept con³denTal.How many keys would be required to achieve this using symmetric cryptosystems?How many key pairs would be required using public key cryptosystems?±ask 5 (6 marks) Provide a de³niTon of the mono-alphabeTc cipher. Describing encoding the message“Security is important” using a mono-alphabeTc cipher of your choosing. What is involved in such abrute force a²ack?±ask 6 (5 marks) Consider our authenTcaTon protocol 4.0, in which Alice authenTcates herself to Bob,which we saw works well (i.e., we found no ´aws in it.). Now suppose that at the same Tme that AliceauthenTcates herself to Bob, Bob must authenTcate himself to Alice. Give a scenario by which ±rudy,pretending to be Alice, can now authenTcate herself to Bob as Alice. (Hint: consider that the sequence ofoperaTons of ap4.0, one with ±rudy iniTaTng and one with Bob iniTaTng, can be arbitrarily interleaved.Pay parTcular a²enTon to the fact that both Bob and Alice will use a nonce, and that if care is not taken,the same nonce can be used, maliciously).

Attachments:

• 1496044557-assign.docx