EECS 122 - COMMUNICATION NETWORKS - SPRING 2001 Homework Assignment #1 - Due 2/5/011. Packet Formats. (3 out of 20)The notation is as in the lectures and notes: a, b, x, y are Ethernet addresses and N1.1, N1.3, N4.1, N4.6 are IP addresses. Computer N1.3 sends a packet to computer N4.6. Select the appropriate formats for the packet asit goes through the links [1], [2], and [3] among the following choices: (Remember the conventions that we explained in class: For Ethernet, [destination address | source address | …] and for IP packets, [source address | destination address | …].)P1: [N1.3 | N4.6 | data]P2: [a | N1.3 | b | N1.1 | data]P3: [b | a | N1.3 | N1.1 | data]P4: [b | a | N1.3 | N1.1 | N1.3 | N4.6 | data]P5: [b | a | N1.3 | N4.6 | data]P6: [x | b | N1.1 | N4.1 | N1.1 | N4.6 | data]P7: [y | x | N1.3 | N4.6 | data]P8: [y | a | N1.3 | N4.6 | data]P9: [x | b | N1.3 | N4.6 | data]Your answers: LINK Format (P1, P2,..., or P9)[1][2][3]N3N2N1N4R1R2R3a N1.3y N4.6b N1.1x N4.1[1][2][3]Student Name: SID: Email: We are trying a paper-free process. Please fill in the information requested at the red locations. Return by email the filled-in form as an email attachment to wlr@eecs before 2/5/01 at noonImportant: The “subject” of the email should be 122S01H1 (if the subject is not correct, your assignment may get lost). If you cannot open the Word file and are using the pdf file, send you solutions as a text email with the same subject.2. Routing Tables [6 out of 20]For the network above, the routers exchange link state messages. For instance, router R1 sends the message [1, N1 | 2, N2 | 3, R3 | 4, R2] that describes what is attached to each of its ports.Describe an algorithm that router R3 can use to reconstruct the map of the network from the link state messages it receives from R1 and R2. Be as concise and precise as you can.N3N2N1N4R1R2R312341231233. Ethernet [6 out of 20]In the network above, the small rectangles are Ethernet interfaces with the Ethernet addresses indicated inside. Let A be the IP address that correspond to the Ethernet address a, and similarly for B - H.Assume that you just installed this network and that you then turn on the devices. The first thing that happens is that device A wants to send a message to device G.Describe the packets that flow on the links [0], [1], …, [9] until that packet reaches G.For instance:[1] [g | a | A | G | data] [0] [g | a | A | G | data][2] [all | b | who is C?] (Here, “all” means that the packet is broadcast.).....Your answer:Switch SwitchHuba b c f g hd e[1][2][3][4] [5][6][7] [8][9][0]4. Ethernet throughput [5 out of 20]In network above, assume that all the links are 10-Mbps links and that all the devices want to transmit at an average rate of R bps. What is the maximum possible value of R? Explain your answer.Switch SwitchHuba b c f g hd e[1][2][3][4] [5][6][7]
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