This preview shows page 1. Sign up to view the full content.
Unformatted text preview: ered a drop upon reaching 10Gbps, how long would it take for it to return to 10Gbps (after undergoing a fast retransmit)?_ ___(in seconds, rounded down to the nearest second) Depending on which answer you gave above, the acceptable answers are: 1,000sec or 1333sec. vi) Consider two TCP connections whose throughput obeys the TCP throughput equation listed above. The first TCP connection has the following parameters: MSS = 1000 bytes, RTT = .2msec, drop rate = .5% The second TCP connection has the following parameters: MSS = 2000 bytes, RTT = .1msec, drop rate = 8%. What is the ratio of throughputs (the throughput of the first TCP connection divided by the throughput of the second TCP connection)?___ 1 ____ vii) Consider the plot (on the following page) of CWND versus time for a TCP connection. At each of marked marked points along the timeline in the figure on the next page, indicate what event has happened, or what phase of congestion control TCP is in (as appropriate), from the following set: (a) Slow-Start, (b) Congestion 4 Avoidance, (c) Fast Retransmit, (d) Timeout. A.__ a___ B.__ c___ C.__ b___ D.__ c___ E.__ b___ F.__ d___ G.__ a___ Assume CWND is 10,000 right before F, what is the value of SSTHRESH at G? _5000 _ 5 CWND t
A BCD E F G 6 3. DNS Basics [5 points] Consider Host A in domain berkeley.edu, with a local DNS server (call it B. The rest of the DNS infrastructure includes: a) Root b) Tree c) TLD server for .com d) TLD server for .edu e) TLD server for .org f) Authoritative server for foo.com g) Authoritative server for berkeley.edu h) mine.foo.com i) mine.berkeley.edu A asks B to resolve hostname mine.foo.com. Assume there are no cached entries relevant to this request. Write down the steps taken to resolve foo.com and respond to A. Use the letters above for your answers. Step 1: B contacts _a__ and gets the IP address of what host?_ c_ Step 2: B contacts _c_ and gets the IP address of what host?__ f_ Step 3: B contacts _f__ and gets the IP address of what host?__ h_ Step 4: B contacts A and gives it the IP address of what host?__ h__ 7 4. HTTP [10 Points] Consider a client accessing a base HTML page with three URL references to images to be displayed in the page; the images reside on the same se...
View Full Document
- Spring '11