Sale!

CMSC 621 PROJECT 1 (ADVANCED OPERATING SYSTEMS) solved

Original price was: $35.00.Current price is: $28.00.

Category:

Description

5/5 - (1 vote)

In this programming assignment you are to implement a Centralized Multi-User
Concurrent Bank Account Manager. The system has two important components.
1. Bank Server
The server program that services online requests for account manipulations
and maintains all customer records correctly.

2. Clients
Customers are clients of the bank server and use its services to update bank
accounts. The operations that can be performed on an account
are: withdrawal of an amount from an account and deposit of an amount
into an account. Additionally, the bank server can have it’s own service that
periodically deposits an interest amount to each account based on some
fixed rate.

A pictorial representation of the system is as shown in the figure below.
The components of the system and their functionalities to be implemented are as
follows:
1. Server
The server receives queries from customers (ATM clients, Clients/Billing
2
agencies performing online transactions etc.) for operations on accounts.
The server should have the following functionalities:
1. Should be able to accept multiple concurrent customer requests (i.e.,
must be multi-threaded)

2. It should provide locking/protection for access to an account records
during shared access (i.e., a user might be depositing money into his
account and at the same time an online billing agent might be
withdrawing money from the same account). Such cases need to be
correctly handled by protecting variables in the critical section.

3. Maintain correctness of records at each record, (i.e., allow withdrawal
from an account only if it has sufficient funds etc.)
4. To create a set of records at the server initially, you can use an input
file that the server reads and creates account information. You can
generate your own input file. For testing, we will use our own file.
However, name the file Records.txt.
An example input file format could be:
101 Peter 16000
102 John 1200
103 Gambo 11000
.
.

The format for each line being: account number, name, balance
amount (space separated)
2. Client
A client issues requests to the server from a transaction based on account
numbers.

Client functionality:
1. Issue withdrawal or deposit requests.
2. For ease of testing and to make experiments bigger, the clients can
issue requests at fixed time intervals. A client can read an input file for
transaction information and perform those tasks accordingly.
For example, following is a format you can use to generate input for
3
each client and use it in experiments. Create your own file. However,
call it Transactions.txt.

10 01 w 200
25 01 d 300
26 05 d 150
.
.
.
Each line of the input file is a transaction request to be issued by the
client and has the following format: timestamp, account number,
transaction type(withdrawal/deposit), amount (space separated)
3. Should receive status of transaction from server and print or log status for
each.

The purpose of this assignment is to get you familiarized with sockets, processes,
threads and synchronization.
You can be creative with this project (like add create new online accounts, which
means add new functionalities, other than mentioned above, at both client and
server etc.).

CONSTRAINTS ON THE IMPLEMENTATION

1. You must use C++ for implementing this project (therefore, your source files
should have extensions of .cc or .cpp. You are welcome to use the STL
classes). You must test your code on a linux machine/machines. Testing it on
a Windows and/or Unix (MAC) machine is not acceptable.
2. You must create a Makefile with at least two targets.
a. clean: “make clean’’ should clean all the object files in the directory.
b. compile: “make compile’’ should compile the code and create two
linux executables, server and client.
4

Some things to keep in mind:
• The server should be able to handle multiple transaction requests at the
same time. This could be easily done using threads. Be aware of the thread
synchronizing issues to avoid inconsistency or deadlock in your system.
• The server should provide protection for shared simultaneous access to the
same record using semaphores or locks etc.

• No GUIs are required. Simple command line interfaces are fine.
• This is an individual project. Go group collaboration is allowed.

EVALUATION AND MEASUREMENT

Correctness
Demonstrate that your system works correctly according to requirements stated in
the description of the system.
1. Show that the server preserves correctness of transactions by deducting
money only when available, is multi-threaded and accepts requests
concurrently.

2. Show use of locks/semaphores that protects simultaneous access to the
same account. i.e., design a test experiment(s) to demonstrate this using logs
or message display during events.

Scalability

1. Use a set of periodic requests at each client (e.g., each sending a request
every 2 secs) and vary the number of clients connected to the server.
Measure the average time to complete each transaction for each client. Plot
a graph to show average time to complete each transaction as number of
clients are increased (say from 1 to 100).

2. The same experiment can be repeated by fixing the number for clients (to
say 25) and then varying the request rate. i.e., one request every 0.1, 0.2, …1
5
secs etc. Measure and plot the average time to complete each transaction as
the request rate is varied.
These are guidelines only, so be creative in what can be evaluated and measured
as part of your experiments to test the system.

WHAT YOU WILL SUBMIT

Each program must work correctly and be documented. You should submit a zip of
two directories.
1. Directory 1 (name: src): The first directory should have all your source code
and the Makefile. Additionally, the directory should have a separate (typed)
document of approximately two pages describing the overall program design,
a description of “how it works’’ (how to compile and run the code), and
design tradeoffs considered and made.

Describe clearly how multiple
threads and synchronization are handled. Also describe possible
improvements and extensions to your program (and sketch how they might
be made). The directory should also have a copy of the output generated by
running your program.

When the server receives data, have your program
print a message “data received from client s‘’ . When a client is sent data by
the server, have your program print messages for the data being sent by the
server and for the data being received by the client.

2. Directory 2 (Name: Results): The directory should have a document which
describes the performance results (graphs that are discussed above).
3. The zip of the two directories should be submitted using slack as described
below.

GRADING

• Program Listing
o works correctly ————- 50%
o in-line documentation ——– 15%
• Design Document
o quality of design ———— 15%
o understandability of doc ——- 10%
• Thoroughness evaluation ———- 10%
6

SUBMISSION

Assignment given out: Monday, September 18
th, 2017
Assignment due: Friday, October 6
th, 2017, 11:59 PM.
There would be no extensions allowed, unless the instructor decides to extend the
deadline.

SUBMISSION METHOD

We will be using slack to submit your assignment. All you need to do is to message
the TA with the .zip file. The TA will discard all messages received after the deadline.
Please accept my invite for slack. If you have any questions, please ask.