CS 925 Advanced Computer Networks

Notes


Slides and sketches drawn on the document camera in class are posted here after each lecture. These are intended as a supplementary materials, you are expected to take notes during the class. You will be tested on points covered in class but not necessarily reflected here.

Week 1

Tuesday, 1/22
Course overview. Fundamental network performance measures. Methods to study network performance. Recap of basics of probability.
Thursday, 1/24
Standard probability distributions and their applicability in networking. Stochastic modeling of protocol performance. Stop and Wait protocol under packet loss.

Week 2

Tuesday, 1/29
Queues in computer networks. Single server queuing system, Kendall notation, basic queuing relationships, Little's formula. M/M/1 Queue. Assignment 1 introduction. Discrete event simulation.
Thursday, 1/31
Fundamental relationships among measures of network performance. Traffic Management. Motivation, layers of traffic management.

Week 3

Tuesday, 2/5
QoS measures and considerations. Node-to-node vs end-to-end actions. Traffic shaping and policing. Token bucket and Leaky Bucket schemes. Traffic flow, soft state.
Thursday, 2/7
Components of QoS mechanisms. QoS in IP. Prioritization of flows. Examples of mechanisms: Weighted Fair Queuing (WFQ), Deficit Round Robin (DRR).

Week 4

Tuesday, 2/12
Random Early Detection (RED). Real-time protocols, RTP/RTCP introduction, RTP/RTCP, RTMP. Video delivery, video delivery metrics.
Thursday, 2/14
HTTP Live Streaming, DASH. OTT video delivery. Virtual circuit service.

Week 5

Tuesday, 2/19
Assignment 2 introduction. Example of virtual circuit service: MPLS. MPLS protection and service restoration.
Thursday, 2/21
Assignment 1 discussion. Service restoration, protection mechanisms. 1+1, 1:1, ring protection. Traffic engineering in transport layer: TCP congestion control.

Week 6

Tuesday, 2/26
Guest Lecture: Bob Noseworthy (UNH-IOL) - Time Sensitive Networking. For more resources see Piazza post.
Thursday, 2/28
Assignment 3 introduction. TCP SACK, TCP congestion control, TCP variants. Network latency.

Week 7

Tuesday, 3/5
Guest Lecture: Daniel Moss - Modeling DSL.
Thursday, 3/7
Exam 1

Week 8

Tuesday, 3/19
Sources of latency in communication networks. Cut-through switching, RDMA.
Thursday, 3/21
Latency in access networks. Latency of a web transaction: DNS and security.