MY-ASSIGNMENTEXPERT™可以为您提供princeton COS461 Computer Networking计算机网络的代写代考和辅导服务！
这是美普林斯頓大学 计算机网络课程的代写成功案例。
COS461课程简介
This course studies computer networks and the services built on top of them. Topics include packet switching, routing and flow control, congestion control and quality-of-service, Internet protocols (IP, TCP, BGP), network security, network management, software defined networking, and the design of network services multimedia, file and web servers.
Course Format
The course will meet twice a week for 50-minute lectures. Additionally, there will be one precept per week.
Assignments for the course will be lab-based programming assignments.
Recommended Background
Prerequisite: COS 217. Although not required, taking either COS 318 or 333 before COS 461 is helpful for the programming assignments.
Prerequisites
Late Policy
We understand that sometimes life events occur and that it’s not always possible to meet every deadline. As such, we are willing to accept late assignments according to the following policy:
You start the term with a grace period “balance” of 96 hours.
Each assignment will be due at 11:59 p.m. (Princeton Local Time) on the due date.
For each assignment, every hour late (or fraction thereof) that you turn in the assignment will subtract one hour from your grace-period balance. For example, if you turn in your assignment at 1:02 a.m. on the date after the due date, we will count this as two hours against your grace period.
As long as your grace period balance is positive, you can turn in any assignment late without penalty.
COS461 Computer Networking HELP（EXAM HELP， ONLINE TUTOR）
Frank Fandango runs a 10Mbit/s Ethernet between the CMU campus and the homes of his friends. All of these hosts are in a single broadcast domain. Fortunately, they are located just within the maximum distance of an Ethernet. The total size of an Ethernet can be about 2.5 kilometers, , and an Ethernet has a minimum packet size of 512 bits.
Frank upgrades his network to $100 \mathrm{Mbit} / \mathrm{s}$ Ethernet, and notices that when only one person sends at a time, or when he sends very large packets, his network works. But when many people send very small packets, things don’t work at all.
(a) Explain how a minimum packet size can help to detect collisions in Ethernet:
(b) Help Frank out. Compute the threshold of how big packets must be in order for things to work:
(c) One solution that Frank came up with is to raise the minimum packet size to the answer from part (a). Suppose that Frank cannot modify the minimum packet size, move the endpoints, lay new cable, or change the software or configuration on the endpoints. You may add new devices to the network. How could Frank change the topology to fix his problems anyway?
Imagine the Internet is divided into the Autonomous Systems shows below. In this problem we assume NO subnetting and NO supernetting and NO CIDR is used. A packet is being sent from Host H1 to Host H2. The packets takes the following route: $\mathrm{H} 1 \longrightarrow \mathrm{R} 1 \longrightarrow \mathrm{R} 2 \longrightarrow \mathrm{R} 3 \longrightarrow \mathrm{R} 4 \longrightarrow \mathrm{R} 5 \longrightarrow \mathrm{R} 6 \longrightarrow$ H2
Some information: $\mathrm{R} 2, \mathrm{R} 3, \mathrm{R} 4$, and $\mathrm{R} 5$ are gateway routers. Assume that there are many routers and networks within each AS that are not shown. Assume also that there are NO default entries in routers. Please answer the questions below in 10 words or less. We are NOT looking for numerical answers.
(a) Which of the labeled routers above likely use the BGP routing algorithm to create their forwarding tables?
(b) How many entries does R1’s forwarding table have?
(c) Assume that host H1’s IP address is 205.96.17.172, What can we say about the IP address of R1
(d) Give an example of an entry in R1’s forwarding table (don’t leave out any fields).
(e) How many entries are there in R2’s forwarding table?
(f) Suppose AS $X$ thinks that AS $Y$ drops too many packets. Using only BGP, is it possible for AS $X$ to implement a policy stating that “traffic outbound from my AS should not cross $Y$ ?” Why or why not?
(g) Now suppose AS $X$ thinks that AS $Y$ generates a lot of illegal file sharing traffic. Using only BGP, is it possible for AS $X$ to implement a policy stating that, “I don’t want to carry traffic from $Y$ to my customers?” Why or why not? Assume that AS $X$ does not want to deny transit to traffic from any other AS.
Maggie decides to start a small company. She asks her ISP, Acme Networks, to give her enough addresses for 1200 hosts. ACME allocates a subblock from the 192.1.* address range that they own and tells Maggie to use the following addresses:
$$
\begin{aligned}
& \text { 192.1.0.* } \
& \text { 192.1.1.* } \
& \text { 192.1.2.* } \
& \text { 192.1.3.* } \
& \text { 192.1.4.* }
\end{aligned}
$$
(a) Maggie has heard that the size of the Internet routing table has grown to huge proportions, and that to be a good citizen, she should announce the fewest number of routes possible to exactly cover her IP addresses.
Under CIDR, what is the smallest set of network numbers that the rest of the world would use to describe Maggie’s networks (please use address \& prefix format – e.g. 128.2/16)?
(b) Maggie has a second ISP that she uses, RoadRunner Networks. She announces some of her network addresses to both Acme and RoadRunner. (Maggie hadn’t talked to you yet-these announcements do not correspond to the answers you provided to the previous question). As a result, some router far away in the network produces a forwarding table with the following entries:
\begin{tabular}{ll}
Destination & Next Hop \
\hline $192.1 / 16$ & 1.2 .3 .4 \
$192.1 .0 / 23$ & 1.2 .3 .5 \
$192.1 .4 / 24$ & 1.2 .3 .6 \
$192.1 .1 / 24$ & 1.2 .3 .7
\end{tabular}
Which next hop should the router use for a packet destined to 192.1.0.1?
MY-ASSIGNMENTEXPERT™可以为您提供PRINCETON COS461 COMPUTER NETWORKING计算机网络的代写代考和辅导服务！
