Announcements



Final exam scores and grades

Posted by: Matt Bishop
Date: Jun 12 at 4:00pm

Hi, folks,

Final exam scores are now available; totals on Canvas, graded final exams on Gradescope. My solutions are available from the exam information page.

I have posted to Canvas everyone’s scores for homework, labs, extra credit, midterm, quizzes, and final. I have incorporated all the updates that people have pointed out so far. Please check these over.

If there are any problems, please let me know no later than 5pm on Monday, June 14 (that’s this coming Monday) so I can submit grades on time.

Be aware that Canvas scores take into account deductions for being late, while Gradescope scores do not, so the two may be different, Where there was a late deduction, I noted it in the Canvas area of the assignment.

It&tsquo;s been a pleasure having you all in this class.

Hope this helps, and stay safe,

Matt Bishop


IMPORTANT — Check your scores! (UPDATED)

Posted by: Matt Bishop
Date: Jun 9 at 2:38pm

Hi, folks,

I have posted (and updated when needed) to Canvas everyone’s scores for homework, labs, extra credit, midterm, and quizzes.

Please check these over. I will use these, plus the score on your final, to assign grades for the class.

Be aware that Canvas scores take into account deductions for being late, while Gradescope scores do not, so the two may be different, Where there was a late deduction, I noted it in the Canvas area of the assignment.

If there are any problems, please let me know by Friday of this week (that is, by June 11).

Hope this helps, and stay safe,

Matt Bishop


Reminder about the Final

Posted by: Matt Bishop
Date: Jun 7 at 11:13pm

Folks,

I want to eliminate any confusion about the need to justify your answers. On the final, except for the first 5 (multiple choice) questions, you must justify your answers and, if you do not, you will lose points whether you get the right answer or not

. At the top of each page after the first on the final, the header says “Unless explicitly stated otherwise, justify your answers!&rdqio

You may justify your answers for the multiple choice questions; if you do and get the wrong answer, you may well get partial credit.

Hope this helps, and stay safe,

Matt Bishop


Lab 3 Certificate Problem

Posted by: Muwei Zheng
Date: Jun 7 at 11:18am

Hi everyone,

Some of you may confused that the certificates you were found in lab 3 looked weird, they didn’t have common name match with anything like *.*.cnn.com. That’s because the communication you were looking at was not to www.cnn.com, but to cdn.cnn.com. CDN stands for Content Delivery Network, it deliveries contents from webservers who use its service. The main advantage is to greatly reduce latency. And it is also a very effective way to protect websites against DoS attack. CDN is out of the scope of this lab so we won’t deduct points for that. This is just for your information why you are getting different certificates that you expected.

Best,

Muwei


Office hours this week

Posted by: Matt Bishop
Date: Jun 7 at 8:56am

Folks,

I will be holding office hours on Monday (today) and Tuesday (tomorrow) at 2pm Pacific time.

Hope this helps, and stay safe,

Matt Bishop


Office Hour Rescheduled

Posted by: Matt Bishop
Date: Jun 2 at 9:59am

Folks,

Unfortunately I have been called away at 11am, so I cannot make my morning office hour.

I will hold a make-up office hour tomorrow at 9am.

Hope this helps, and stay safe,

Matt Bishop


TA office hour reschedule

Posted by: Muwei Zheng
Date: Jun 1 at 1:13pm

Hello everyone,

Can'’t get back in time, will reschedule office hour to Thursday afternoon same time.

Best,

Muwei Zheng


Homework 4, question 3

Posted by: Matt Bishop
Date: May 24 at 2:49pm

Folks,

There seems to be some confusion about question 3. Here is how to look at it.

In a time-based one-time password system, a password is good for some time interval. Let’s say that interval is 1 minute long; then the valid password changes. Now, I log in at the beginning of that time interval using the valid password. It takes 10 seconds, so there are 50 seconds remaining in the interval. The password I used to log in is invalidated. Why? What is the threat this guards against?

Hope this helps, and stay safe,

Matt Bishop


Homework #4 Now Available

Posted by: Matt Bishop
Date: May 14 at 11:00pm

Folks,

Homework #4 and Extra Credit #4 are both now available. Please submit them on Gradescope.

Hope this helps, and stay safe,

Matt Bishop


Midterm grades posted

Posted by: Matt Bishop
Date: May 12 at 7:14pm

Folks,

The subject says it all.

Hope this helps, and stay safe,

Matt Bishop


Video for today’s lecture fixed

Posted by: Matt Bishop
Date: May 7 at 1:08pm

Folks,

The video for today’s lecture is now available.

Thanks to those who let me know of the problem.

Hope this helps, and stay safe,

Matt Bishop


Change in my office hours

Posted by: Matt Bishop
Date: May 5 at 2:40pm

Folks,

I need to leave early today, so I have shifted my office hours to 2:30pm–3:30pm today. My apologies for the short notice.

As always, you can email me or post to Piazza (public or private) and I will answer as quickly as I can.

Hope this helps, and stay safe,

Matt Bishop


TA office hour reschedule

Posted by: Muwei Zheng
Date: May 3 at 2:29pm

Hello everyone,

TA office hour tomorrow will be reschedule to Thursday at the same time. Sorry for the inconvenience.

Best,

Muwei Zheng


Homework 2 Graded

Posted by: Matt Bishop
Date: May 3 at 6:19am

Folks,

Grades for Homework 2 and Extra Credit 2 are posted on Gradescope. The scores do not take into account lateness, so bear that in mind. I will put them onto Canvas in a bit.

Hope this helps, and stay safe,

Matt Bishop


Homework 3 Due Date

Posted by: Matt Bishop
Date: Apr 30 at 11:06pm

Folks,

This has been changed to May 10 (Monday), with late assignments accepted through May 12.

Hope this helps, and stay safe,

Matt Bishop


Homework 2 Submission

Posted by: Matt Bishop
Date: Apr 20 at 1:05pm

Folks,

Homework 2 is to be submitted on Gradescope. Please upload it there and indicate where your answers to each question is. If you have already uploaded it into Canvas, please upload it again and indicate where on the pages your answers to the questions are.

Hope this helps, and stay safe,

Matt Bishop


Update to Error Messages

Posted by: Matt Bishop
Date: Apr 16 at 1:25pm

Folks,

I updated two error messages.

First: add a newline to the first error message:

Second, the “u” in “usage” should be capitalized in the third error message:

I've included the other error messages below (the ones referred to above are corrected).

Errors in invoking the program (in all cases, %s is replaced by the name of the program):

If argv[0] is NULL: "access (argv[0] NULL!)"
If no arguments given: "usage: %s [ -g ] name file1 ...\n"
If -g given and no group is given: "usage: %s: -g requires group name\n"
If no file or directory named: "%s: need at least one file or directory!\n"

Numbers (here, %s is replaced by the string representing the number):

If number is too big to be represented: "%s: number too big\n"

User and Group (here, %s is replaced by the group or user name):

User does not exist: "%s: no such user\n"
Group does not exist: "%s: no such group\n"

Hope this helps, and stay safe,

Matt Bishop


Error messages in access program

Posted by: Matt Bishop
Date: Apr 14 at 11:37am

Folks,

Someone asked what error messages the program access would print. Here are the ones I have. Remember these go on the standard error, not the standard output:

Errors in invoking the program (in all cases, %s is replaced by the name of the program):

If argv[0] is NULL: "access (argv[0] NULL!)"
If no arguments given: "usage: %s [ -g ] name file1 ...\n"
If -g given and no group is given: "usage: %s: -g requires group name\n"
If no file or directory named: "%s: need at least one file or directory!\n"

Numbers (here, %s is replaced by the string representing the number):

If number is too big to be represented: "%s: number too big\n"

User and Group (here, %s is replaced by the group or user name):

User does not exist: "%s: no such user\n"
Group does not exist: "%s: no such group\n"

Hope this helps, and stay safe,

Matt Bishop


TA office hour reschedule this week

Posted by: Muwei Zheng
Date: Apr 13 at 12:37pm

Hi everyone,

TA office hour today will be rescheduled to Thursday at same time. Sorry for the inconvenience. And feel free to send me emails if you have any questions.

Best,

Muwei


No Office Hours Today

Posted by: Matt Bishop
Date: Apr 12 at 9:50am

Folks,

Unfortunately, I have to cancel both office hours today. Apologies for the late notice.

Hope this helps and stay safe,

Matt Bishop


Lab 1 Submission Instructions

Posted by: Matt Bishop
Date: Apr 8 at 12:18am

Folks,

The lab 1 instructions now include how to submit it. Look at revision 1. It’s now on Canvas; see the lab 1 assignment.

Hope this helps, and stay safe,

Matt Bishop


My Office Hours

Posted by: Matt Bishop
Date: Apr 6 at 9:40am

Folks,

Here are my office hours, as of now; I may change them in the future. If so, I will let everyone know.

or by appointment (send me email to arrange this). All are over Zoom, of course; I am using the class Zoom link for these, but I will disable the recording as soon as I come in.

I have updated the General Information with these times.

Hope this helps, and stay safe,

Matt Bishop


Discussion Section

Posted by: Muwei Zheng
Date: Apr 5 at 12:20pm

Hello everyone,

Discussions start from this week, Apr. 5th. We will use the same zoom link as we used for the class. Hope to see you guys there!

Best,

Muwei Zheng


Videos

Posted by: Matt Bishop
Date: Mar 29 at 6:05pm

Folks,

I’ve posted the video, a rough transcript, and the chat room contents for the first lecture. The first is a link to video.ucdavis.edu, where the video resides, and the other two are uploaded directly to Canvas.

Go to the ECS 153 home page on Canvas, and click on Lecture Outlines. You’ll see a list of lectures (only one so far) and links to the video, rough transcript, and chats.

Hope this helps, and stay safe,

Matt Bishop


Piazza

Posted by: Matt Bishop
Date: Mar 29 at 11:09am

Hi, folks,

I have set up Piazza. It’s accessible from Canvas. Below is the blurb. The link is there; it’s

https://piazza.com/ucdavis/spring2021/ecs153a01a02sq2021

You can also sign up from Canvas, I believe (but am not sure). You are of course still welcome to email me and/or the TA.

Hope this helps, and stay safe,

Matt Bishop

------------------------

This term we will be using Piazza for class discussion. The system is highly catered to getting you help fast and efficiently from classmates, the TA, and myself. Rather than emailing questions to the teaching staff, I encourage you to post your questions on Piazza. If you have any problems or feedback for the developers, email team@piazza.com.

Find our class signup link at: https://piazza.com/ucdavis/spring2021/ecs153a01a02sq2021