Universitatea Babeş-Bolyai Cluj-Napoca
Facultatea de Matematică şi Informatică
Ciclul de studii: Licenţă
Domeniul: Informatică
Programul de studii: Informatică - în limba engleză
Limba de predare: Engleză

SYLLABUS

I. General data
Code	Subject	
MIC0009	Congestion Management in Computer Networks	

Semester	Hours: C+S+L	Category	Status	
5	2+0+2	speciality	optional	

II. Full status faculty members
Name and	Scientific	Didactic	Chair	Type of activity	
surname	title	title		C	S	L	
BUFNEA Darius-Vasile	Ph.D.	Lect.	Computer Systems	*			

Associated faculty members
Name and	Scientific	Institution	Type of	Type of activity	
surname	title		position	C	S	L	

III. Course objectives
The Congestion Management in Computer Networks class prepares the students to deal with congestion as a negative phenomenon that affects the working performance of the Internet. Students, as future system or network administrators must acquire specific knowledge to successfully identify congestion causes and apply best practice methods to reduce congestion consequences. As future software developers, students must learn how to design and implement healthy Internet communication protocols that must be congestion aware when interact with congestion affected areas.	

IV. Course contents
This course covers the congestion phenomenon in Internet. It presents the main congestion types and their causes. The course also presents the main mechanisms used in order to prevent or to deal with congestion. There are to types of congestion control mechanisms used in Internet. One is implemented at peers end inside the transport protocol stack. The second one is implemented at core Internet routers level. The course presents specific congestion control algorithms such as slow start, implemented inside the TCP protocol or RED (Random Early Detection) implemented at network level inside transport routers.	

V. Bibliography
Jacobson, V., Congestion Avoidance and Control, Proceedings of SIGCOMM 88, Stanford, CA, August 1988, ACM.

Floyd, S., Jacobson, V., Random Early Detection Gateways for Congestion Avoidance, IEEE/ACM Transactions on Networking, 1(4), pp. 379-413, 1993.

Floyd, S. and Fall, K., Promoting the Use of End-to-End Congestion Control in the Internet, IEEE/ACM Transactions on Networking, Vol. 7, No. 4, pp. 458-472, 1999.

Balakrishnan, H., Seshan, S. The Congestion Manager, IETF RFC 3124, June 2001.

Sarolahti, P., Kuznetsov, A., Congestion Control in Linux TCP, Proceedings of USENIX 2002/Freenix Track, pp. 49-62. Monterey, CA, USA, June 2002.

Bufnea, D. V., Campan, A., Darabant, A.S., Fine-Grained Macroflow Granularity in Congestion Control Management, in Studia Universitatis, Vol. L(1), pp. 79-88, 2005.

Campan, A., Bufnea, D. V., Delimitation of Macroflows in Congestion Control Management Using Data Mining Techniques, 4th ROEDUNET International Conference, Education/Training and Information/Communication Technologies - ROEDUNET '05, Romania, pp. 225-234, 2005.

Brown, M. A., Traffic Control using tcng and HTB, http://tldp.org/HOWTO/Traffic-Control-tcng-HTB-HOWTO/, April 2006.

Bufnea, D., Controlul si optimizarea traficului in retele de calculatoare, PhD Thesis, 2007.

Bufnea, D. V., A New Method for Macroflows Delimitation from a Receiver's Perspective, in the International Journal of Computer, Communication & Control - proceedings of the IEEE 2nd International Conference on Computers, Communications & Control (ICCCC 2008), Felix Spa, Romania, Vol. III (2008), pp. 201-205.	

VI. Thematic of didactic activities per weeks
Week 1. Congestion as a negative phenomenon that affects the Internet. Congestion types.

Week 2. Main causes of Internet congestion.

Week 3. Implicit congestion notification using packet dropping. Explicit congestion notification using the ECN header bit filed.

Week 4. Congestion control at the transport protocol level.

Week 5. TCP congestion control protocol. Slow start algorithm.

Week 6. TCP congestion control inside the Linux TCP/IP stack.

Week 7. Congestion control at the transport level. Active queue management control algorithms.

Week 8. RED algorithm. Per flow scheduling.

Week 9. Binomial congestion control algorithms.

Week 10. Congestion control for multimedia streams. Constraints regarding the congestion control of multimedia streams.

Week 11. Congestion managers. Congestion control inside a congestion manager.

Week 12. Macroflows. Nature of a macroflow and its granularity.

Week 13. Fine-grained macroflow granularity at the stream’s source level.

Week 14. Fine-grained macroflow granularity from the receiver’s perspective.	

VII. Didactic methods used
The main teaching methods used in the course are: exposition, discussions, individual study, home-works, quizzes, practical projects. The lectures are based on the bibliography entries presented above: books, articles, web-sites. The practical projects are solved during the lab hours and at home.	

VIII. Assessment
The activity ends with a written exam (grade E). During the semester, the students will prepare several lab projects (grade L). The final grade is the average of the above grades: Final Grade = 50%E + 50%L. In order to successfully pass the exam, the final grade and each of its components have to be at least 5.	

IX. Additional references
Stevens, W., TCP Slow Start, Congestion Avoidance, Fast Retransmit, and Fast Recovery, IETF RFC 2001, January 1997.

Nichols, K., Blake, S., Baker, F., Black, D., Definition of the Differentiated Services Field (DS Field) in the IPv4 and IPv6 Headers, RFC 2474, December 1998.

Ramakrishnan, K. and Floyd, S., A Proposal to Add Explicit Congestion Notification (ECN) to IP, RFC 2481, January 1999.

Allman, M., Paxson, V. and Stevens, W., TCP Congestion Control, IETF RFC 2581, April 1999.

Sahni, J., Goyal, P., and Vin, H. M., Scheduling CBR flows: FIFO or per-flow queuing? in Proceedings of NOSS-DAV99, AT&T Learning Center, Basking Ridge, NJ, June 1999.

Paxson, V., Allman, M., Computing TCP's Retransmission Timer, IETF RFC 2988, November 2000.

Katabi, D., Bazzi, I., Yang X., An Information Theoretic Approach for Shared Bottleneck Inference Based on End-to-end Measurements, Laboratory for Computer Science, Massachusetts Institute of Technology, 2001.

Floyd, S., A report on Some Recent Developments in TCP Congestion Control, IEEE Communication Magazine, 39(4), 2001.

Bansal, D. and Balakrishnan, H., Binomial Congestion Control Algorithms, Proceedings of the 20th Annual Joint Conference of the IEEE Computer and Communications Societies, volume 2, pp. 631-640, April 2001.

Ramakrishnan, K., Floyd, S. and Black, S., The Addition of Explicit Congestion Notification (ECN) to IP, IETF RFC 3168, September 2001.

Tanenbaum, A. S., Computer Networks, Fourth Edition,  2002, Prentice Hall.

Andersen, D., Balakrishnan, H., Bansal, D., Curtis, D. and Seshan, S., The Congestion Manager Software, http://nms.lcs.mit.edu/software/CM, Networks and Mobile Systems
group, MIT, 2002.

Nabeshima, M., Yata, K., Performance improvement of active queue management with per-flow scheduling, IEE Proceedings - Communications, December 2005 - Volume 152, Issue 6, p. 797-803.	

	Dean,							Chair head,

	Date,							Course responsible,
								Lect. BUFNEA Darius-Vasile, Ph.D.