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C Program on UNIX
Bid Request Id: 7711
Bookmark in my 'To Do' list
Posted by: shotglass (9 ratings)
(Software buyer rating 10)
Posted: Jan 18, 2002
2:26:16 PM EDT
Bidding Closes: Jan 22, 2002
12:27:19 AM EDT
Viewed (by coders): 242 times
100% of work was accepted by buyer. Coder account has been credited.
Max Accepted Bid: Bidding is closed
Project Type: Personal Project / Homework Help
Bidding Type: Open Auction
Categories: C++ / C, UNIX
Enter chat room for this bid request
(0 active users at Jan 20, 2003 4:17:04 PM EDT)

Ethernet Switch
Program in ANSI C on UNIX,Use of semaphores & threads

Create program that simulates single switch with numClients machines sending messages through it.
Switch will be modeled by main thread. Will be several parameters:

1.numClients-number of ports. Assume that each port is connected to single machine (client). Thread will be created for each
2.rngSeed-seed for random number generator
3.maxCount-number of times each client will attempt to send essage
4.sendProbability-probability ( × 10000) that client will send message on each attempt

Will be data structure shared among all threads. an array, one for each
client, of port s described below.

source // sender's address
destination // destination address
data // an integer value

message // described above
empty // binary semaphore (initially 1)
mutex // binary semaphore (initially 1)
maddr // address of connected machine

Entry port[i].message represents packet input on port[i] of switch. Ports are numbered 0 through numClients
- 1 . Entry port[i].maddr is the information thats maintained in forwarding table. You wont need to keep seperate
forwarding table. The field maddr with index is sufficient. You will need to update this field accordingly, its initially set to

Output of simulation will be list of messages forwarded by switch. For each forwarded message a line will be printed
indicating output port , source machine address , destination machine address , and data First message arrived on port 1:

0 1234567 9876 10125
2 1234567 9876 10125
3 1234567 9876 10125
1 74855 1234567 77449201

Switch thread will implement following pseudocode.

srand( rngSeed )
InitClient( numClients ) // supplied function
Create array of ports
Initialize array of ports
Initialize sendingClients to numClients
for i = 0 to numClients - 1
Start new thread for client attached to port i
while sendingClients > 0
for i = 0 to numClients - 1
if message on port i // new entry in port[i]
update forwarding table if new information
search forwarding table for output port
if port found
send message out port
send message out all ports except i

Check out attached to continue

Complete and fully-functional working program(s) in executable form as well as complete source code of all work done. Complete copyrights to all work purchased.

Special Conditions / Other:
Program MUST be completed by Monday January 28th at 12:00pm Central Time

Additional Attached Files

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Name   Bid Amount 
Date   Coder Rating  
This bid was accepted by the buyer!
(49 ratings)
in Braila, Braila
$25 (USD) Jan 18, 2002
5:48:54 PM EDT
Accept my bid and you will have your program in 48 hours.


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