Lecture 0
Organizational
Course Information
Prof. Anja Feldmann, PhD
Organization, Tutorials, Tutors, Exam, Contact, Intro
This video gives an overview on the course organisation, tutorials, homework assignments, schedule, online tutorials and so on.
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Lecture 1
Introduction - Part1
Internet, Protocols
Video 1 of 3 for this lecture.
Prof. Anja Feldmann, PhD
Goals, Terminology, Protocols, Nuts and bolts, ISPs, RFC, IETF,
This video is part of the first lecture with technical content. We will take a first look on what the Internet is and what role protocols play.
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Lecture 1
Introduction - Part2
Network Edge
Video 2 of 3 for this lecture.
Prof. Anja Feldmann, PhD
Edge, Network,
This video is part of the first lecture with technical content. In this video we will look at the Network edge and try to give you a feeling for the terminology. We will have more in-depth views later in the course.
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Lecture 1
Introduction - Part3
The Network Core
Video 3 of 3 for this lecture.
Prof. Anja Feldmann, PhD
The Core, Network Core, Routing, Forwarding, Queueing, Store-and-forward
This video is part of the first lecture with technical content. We will look at the network core, why the Internet mostly uses packet switching and learn what role a Tier 1 provider plays.
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Lecture 2
Introduction - Part4
Delay, loss, and throughput
Video 1 of 2 for this lecture.
Prof. Anja Feldmann, PhD
delay, loss, throughput, performance
This video is part of the first lecture with technical content. In this part we will take a closer look at Performance, namely: Delay, loss, and throughput.
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Lecture 2
Introduction - Part5
Layers, History, Security
Video 2 of 2 for this lecture.
Prof. Anja Feldmann, PhD
Layers, Service models, Security, History
This video is the last part of the first lecture with technical content. We wil talk about protocol layers, service models, Security and the history of the Internet
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Lecture 3
Application Layer - Part1
Client-Server, Peer2Peer
Video 1 of 4 for this lecture.
Prof. Anja Feldmann, PhD
Layers, Application Layer, Client-Server, Peer-to-Peer
This video is the first of two parts on the Application Layer. We will take a look at different Methods of Communication, e.g., Client-Server and Peer-to-Peer, and talk about how processed fit into that scheme.
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Lecture 3
Application Layer - Part2
Sockets, Layers, Protocols
Video 2 of 4 for this lecture.
Prof. Anja Feldmann, PhD
Layers, Application Layer, Sockets, adressing sockets, transport protocols
This video is the second of two parts on the Application Layer. We will talk about sockets, adressing themn, protocols, Internet transport protocols and transport service requirements of applications.
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Lecture 3
Application Layer: HTTP Part 1
HTTP Basics
Video 3 of 4 for this lecture.
Prof. Anja Feldmann, PhD
Layers, Application Layer, protocols, HTTP, protocols by example, HTTP messages, HTTP Request, HTTP Response
This video is part of the lecture series on the Application Layer. It is the first of two videos on HTTP, the HyperTextTransferProtocol, within that series. We will look at the basic modes of operation of HTTP and also show some examples of using a telnet client to send HTTP requests.
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Lecture 3
Application Layer: HTTP Part 2
HTTP Caching and Cookies
Video 4 of 4 for this lecture.
Prof. Anja Feldmann, PhD
Layers, Application Layer, protocols, HTTP, protocols by example
This video is part of the lecture series on the Application Layer. It is the second of two videos on HTTP within that series. It covers some of the 'advanced' features of HTTP, including how this stateless protocol can be used to handle state using cookies and how the most simple form of authentication works.
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Lecture 4
Application Layer: DNS
The Domain Name System
Oliver Gasser
Layers, Application Layer, protocols, DNS, protocols by example, adresses, PTR, NS, MX, nameserver, dig
This video is part of the lecture series on the Application Layer. We will talk about the largest distributed Database of the world, the DNS, often called the phone book of the Internet.
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Lecture 5
Application Layer: CDNs
Content Delivery Networks
Video 1 of 2 for this lecture.
Prof. Anja Feldmann, PhD
Layers, Application Layer, protocols, DNS, CDN, Content Delivery, Content Distribution, Overlay Networks, Content, Application Mix
In this video we will discuss Content Delivery Networks. Large Networks specialized on providing Content, like Videos, Operating System updates, etc, to a large number of users. We will also talk on what we mean, when talking about content.
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Lecture 5
Application Layer: Email
A look at SMTP, IMAP, POP3
Video 2 of 2 for this lecture.
Balakrishnan Chandrasekaran, PhD
Layers, Application Layer, protocols, Network Programming, Network Protocols, Email, e-mail, SMTP, IMAP, POP, POP3, mail, MUA, Mail User Agent, MTA, Mail Transfer Agent, MDA, Mail Delivery Agent
E-mail is one of the oldest applications on the internet. But it's not just one protocol, it's several! We will take a dive into SMTP, the Simple Mail Transfer Protocol, and talk about message access protocols like IMAP, the Internet Message Access Protocol, and POP3, the Post Office Protocol.
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Lecture 6
Application Layer: Socket programming
Network Application Basics
Prof. Anja Feldmann, PhD
Layers, Application Layer, protocols, Network Programming, Sockets, UDP, TCP, accept(), bind(), listen(), client, server, Network Protocols
The basic building block of each and every network application, be it a ticketing system of a large airline or s simple chat server are network sockets. We will take a look on how you as a programmer use them and what abstractions are in place. You will get a first impression on what is needed to write a network application. This lecture is still part of the Application Layer.
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Lecture 7
Transport Layer
Intro and UDP
Video 1 of 2 for this lecture.
Prof. Anja Feldmann, PhD
Layers, Transport Layer, UDP, User Datagram, Multiplexing, Ports, Sockets, Segments, PDU
In this lecture we will take a look at the Transport Layer and UDP. We will revisit Sockets, Ports and dive right into UDP.
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Lecture 7
Transport Layer: TCP - Part 1
TCP Part 1 of 3
Video 2 of 2 for this lecture.
Prof. Anja Feldmann, PhD
Layers, Transport Layer, TCP, Sequence Numbers, Segments, Header, RFC 793, RFC 1122, RFC 1323, RFC 2018, RFC 2581,
In this video we will take a first look at TCP, it's header structure and Sequence Numbers.
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Lecture 8
Transport Layer: TCP - Part 2
TCP Part 2 of 3
Video 1 of 2 for this lecture.
Prof. Anja Feldmann, PhD
Layers, Transport Layer, RTT, Retransmission, Timouts, State Machine, TCP, Sequence Numbers, ACK generator, Retransmits
This is the second of three videos on TCP. We will cover some of the basic mechanisms that TCP implements to offer reliable data transfer and take a peek under the hood of some state machine in TCP.
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Lecture 8
Transport Layer: TCP - Part 3
TCP Part 3 of 3
Video 2 of 2 for this lecture.
Prof. Anja Feldmann, PhD
Layers, Transport Layer, TCP, window size, state machine, 3-way Handshake, connection management, flow control
This is the third and last video of the series on TCP. We will look into the finite state machine of the protocol, window sizes, connection management and flow control, as well as connection management.
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Lecture 9
Transport Layer: Congestion Control
Congestion, Part 1 of 2
Video 1 of 2 for this lecture.
Prof. Anja Feldmann, PhD
Layers, Transport Layer, Congestion, Congestion Control, Convergence, Congestion Avoidance, Control Model
This is the first of two videos on Congestion. We will take a deep dive into Congestion Control and Avoidance, different Control Models and look at the theory of operations.
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Lecture 9
Transport Layer: Congestion Control
Congestion, Part 2 of 2
Video 2 of 2 for this lecture.
Prof. Anja Feldmann, PhD
Layers, Transport Layer, Congestion, Congestion Control, Fairness, AIMD, Slow start
This is the second of two videos on Congestion. In this part we will focus on TCP Congestion Control and look at some simulations.
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Lecture 10
Transport Layer: TCP Variants
There are many TCPs
Balakrishnan Chandrasekaran, PhD
Layers, Transport Layer, TCP, Variants, Variants, Protocols, Congestion Control, Congestion Avoidance, Congestion Collapse, BBR, Reno, CUBIC, BBR, NDP, Vegas, BIC, Tahoe
We talked a lot about TCP as one of the major transport protocols in the Internet. Suprisingly there is not just one variant of TCP used on the Internet but there exist dozens of slightly modified versions. We will take a closer look at some of the differences in the protocol definitions and how this changes its behavior.
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Lecture 11
Network Layer: Addressing
IP-Addressing and more
Dr. Oliver Gasser
Layers, Network Layer, Addressing, IPv4, IPv6, Multicast, CIDR, NAT, Longest Prefix Match, Subnetting
This Video will start with a short part on the Network Layer and quickly focus on Addressing. What are IP-Addresses, what are the differences between IPv4 and IPv6 concerning addresses. What is Multicast and what are reserved addresses. We will take a look at the differences between Routing and Forwarding and discuss longest prefix matching.
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Lecture 12
Network Layer: Routing Algorithms
Link State and Distance Vector
Dr. Oliver Gasser
Layers, Network Layer, Routing, Dijstra, Algorithms, Distance Vector, DV, Link-state, LS, Dijkstra, Bellman-Ford, Routing, Costs,
In this video we will discuss two well known routing algorithms: Dijkstra' Algorithm and Bellman-Ford. We will introduce a classification of Routing Algorithms and compare Distance Vector and Link-state Routing.
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Lecture 13
Network Layer: Routing (1)
Routing and RIP
Video 1 of 2 for this lecture.
Prof. Anja Feldmann, PhD
Layers, Network Layer, Routing, Historic Protocols, RIP, Algorithms, Inter-AS, Intra-AS, count-to-infinity
In this video we will take a closer look at routing. We will discuss the RIP protocol, which should not be used any more, but can still teach us a lot of valuable lessons.
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Lecture 13
Network Layer: Routing (2)
OSPF - Part 1
Video 2 of 2 for this lecture.
Prof. Anja Feldmann, PhD
Layers, Network Layer, Routing, OSPF, Algorithms, IGP, Intra-AS routing, Link state protocol, Dijkstra, LSA, Multicast, Flooding
This is the first of two videos on OSPF, a commonly used routing protocol inside of an AS. We will discuss the protocol phases and look at some examples.
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Lecture 14
Network Layer: Routing (3)
OSPF - Part 2
Video 1 of 3 for this lecture.
Prof. Anja Feldmann, PhD
Layers, Network Layer, Routing, OSPF, Algorithms, IGP, Intra-AS routing, Link state protocol, Dijkstra, LSA, Multicast, Flooding
This is the second of two videos on the inner workings of OSPF, a commonly used routing protocol inside of an AS.
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Lecture 14
BGP Part 1
Routing: BGP
Video 2 of 3 for this lecture.
Prof. Anja Feldmann, PhD
Layers, Network Layer, Routing, BGP, Algorithms, EGP, Inter-AS routing, Policies, BGP Basics, BGP-4, Stub AS, BGP messages
This is the first of four videos on BGP. We will discuss the Basics of BGP, the Border Gateway Protocol, see what routing policies are, why they are important and take a first look at network architectures.
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Lecture 14
BGP Part 2
Overview continued
Video 3 of 3 for this lecture.
Prof. Anja Feldmann, PhD
Layers, Network Layer, Routing, BGP, Algorithms, EGP, Inter-AS routing, path-vector, OSPF, attributes, local pref, Local preference, route processing, route selection, AS Path, AS-Path
This video will continue the introduction to BGP with more details on the inner workings of the protocol. We will take a look at attributes and how routing decisions are being made.
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Lecture 15
BGP Part 3
Routing Policies
Video 1 of 2 for this lecture.
Prof. Anja Feldmann, PhD
Layers, Network Layer, Routing, BGP, Algorithms, EGP, Inter-AS routing, MED, Multi-homing, Local Preference, Hot Potato Routing, path-vector
In this video we will take a closer look at policies and why they are so important for routing in the Internet. We will take a look how policies are implemented using BGP.
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Lecture 15
BGP Part 4
Advanced Topics
Video 2 of 2 for this lecture.
Prof. Anja Feldmann, PhD
Layers, Network Layer, Routing, BGP, Algorithms, EGP, Inter-AS routing, Intra--AS routing, iBGP, eBGP, e-bgp, i-bgp, BAD GADGET, Confederations, reflectors, routing instability
In this video we will talk about some of teh advanced features of BGP. We will discuss internal and external BGP (iBGP, eBGP), Route reflectors, confederations and sources for routing instability.
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Lecture 16
Anycast
A short insert
Video 1 of 3 for this lecture.
Dr. Oliver Gasser
BGP, Anycast, Routing
This video is a short spotlight on Anycast, as addition to our lectures on Layer three and routing
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Lecture 16
Router Architecture
What is a router?
Video 2 of 3 for this lecture.
Prof. Anja Feldmann, PhD
Routing, Architecture, Router, Hardware, Ports, queueing, fabric, buffering, core, edge, RIB
This lecture aims at giving an overview on what a router ist, how it works and how the architecture with regards to the hardware looks.
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Lecture 16
Link Layer (1)
Part 1
Video 3 of 3 for this lecture.
Dr. Oliver Gasser
Link Layer, Collisions, ALOHA, TDMA, FDMA, CSMA, CSMA/CD, Token Ring, CRC, Parity
This lecture is the first of two on the link layer. This is the lowest layer we discuss and we will take a look at how access to the communication media is handled and what strategies exist to enable cooperation.
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Lecture 17
Link Layer (2)
Part 2
Dr. Oliver Gasser
Link Layer, Ethernet, Switch, Router, Bridge, 802.3, LAN, Hub, Neighbor discovery, ARP
This is the second part on the Link Layer. We will discuss the differences between Hub, Switch, Bridge, and Router, how they evolved, how ARP and neighbor discovery works and close with a comparison between Hub/Switch/Router.
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Lecture 18
Putting it all together
'Live' Demo
Prof. Anja Feldmann, PhD
Topology, tcpdump, DNS, HTTP, TCP, Overview, Adresses, Layers, Internet, UDP, Packets, across mutilple layers
This video is an unscripted recording of a live session that demonstrates how all protocols work together. We show all steps neccessary to perform an HTTP request, across multiple layers.
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Lecture 19
Multimedia
Sound and Video
Video 1 of 2 for this lecture.
Balakrishnan Chandrasekaran, PhD
Multimedia, Streaming, Video, Audio, HTTP, UDP
The first video of our lecture on Multimedia wants to introduce you to the various challenges we face, when we want to deliver multimedia content over the Internet. For this we will dicuss the basics of Audio and Video transmission and the different types of playout, like live-streaming or on-demand delivery.
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Lecture 19
Voice over IP
Realtime Conversations
Video 2 of 2 for this lecture.
Balakrishnan Chandrasekaran, PhD
Voice, Video, VoIP, protocols, playout delay, jitter, recovery
This video is on Voice over IP (VoIP) and takes a look at the protocols that allow us realtime conversation and video calls over the Internet. We will also briefly touch on the (former) architecture of Skype, as one of the first commercial VoIP platforms.
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Lecture 20
Datacenter - Part 1
The physical cloud
Video 1 of 2 for this lecture.
Balakrishnan Chandrasekaran, PhD
Topology, Networks, Top of Rack, TOR, Fat tree, Pods, Datacenters, cloud
In this video we will talk about Datacenters and try to give an overview about the network topolgy used in these networks.
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Lecture 20
Datacenter - Part 2
Characteristics and Challenges
Video 2 of 2 for this lecture.
Balakrishnan Chandrasekaran, PhD
Topology, Networks, Top of Rack, TOR, Fat tree, Pods, Datacenters, Characteristics, Challenges, Layer 2, Layer 3, TCP, Buffers, Configuration, Management
In this video we will discuss some high level characteristics and challenges inherent in designing and running datacenters.
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Lecture 21
Software-defined Networking (SDN)
Part I
Video 1 of 2 for this lecture.
Savvas Zannettou, PhD
SDN, control plane, data plane, management plane,
This video introduces the software defined networking paradigm
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Lecture 21
Software-defined Networking (SDN)
Part II
Video 2 of 2 for this lecture.
Savvas Zannettou, PhD
control and data plane separation, controller, openflow, fault tolerance, challenges,
This video introduces the software defined networking paradigm
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Lecture 22
P4
Programmable Switches
Balakrishnan Chandrasekaran, PhD
Programming Protocol-Independent Packet Processors, P4
In this video we will look at P4, a domain specific language and concept that takes SDN a step further. Not there is no separate controller but the hardware itself is programmable.
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Lecture 23
Signaling
Signaling is everywhere
Video 1 of 4 for this lecture.
Prof. Anja Feldmann, PhD
Signaling, State, SIP, IMS, Multicast, IGMP, State machine
This video is the first in a series on signaling and state. Here we will first talk about signaling and give some examples for signaling in our context. You will see, signaling and state is everywhere and plays a very important role in almost all applications and protocols.
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Lecture 23
State - Part 1
Hard or Softstate?
Video 2 of 4 for this lecture.
Prof. Anja Feldmann, PhD
HTTP, FTP, State, Hard-state, Soft-state, Signaling, inband
In this video we will focus on State and the difference between Hard- and Soft-state. We will take a look at state in HTTP and FTP and discuss the different aspects of hard- vs. softstate.
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Lecture 23
State - Part 2
Model and Evaluation
Video 3 of 4 for this lecture.
Prof. Anja Feldmann, PhD
State, Soft-state, lifetime, timer, evaluation, modeling
This video takes a short look at design principles, models and (performance) evaluation of soft-state.
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Lecture 23
RSVP
Resource Reservation
Video 4 of 4 for this lecture.
Prof. Anja Feldmann, PhD
RSVP, state, protocol design, signaling, reservation, resources
This video is on RSVP, the Resource Reservation Protocol - not the closing "répondez s'il vous plaît" in invitations. We will not discuss RSVP in detail, as it is rather complex, but focus on some parts that are well suited to explain important aspects of signaling.
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Lecture 24
Internet of Things (IoT)
Part I - Introduction
Video 1 of 3 for this lecture.
Florian Streibelt
IoT, ESP8266, Arduino, Atmel, Mechatronics, Evolution, Background, ARM, Microcontrollers, Car ignition, Washing Machine
This is the first of three videos on the Internet of Things (IoT). This part is th Introduction, giving some background on the Development and looking at some Hardware used in Iot.
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Lecture 24
Internet of Things (IoT)
Part 2 - Communication
Video 2 of 3 for this lecture.
Florian Streibelt
IoT, Industrial IoT, Industry IoT, Cloud, Cloud-computing, Healthcare, Energy, Smart Home, MQTT, protocol, TCP, Building Automation, Smart Home, Security, Confidentiality, Availability, Privacy
This is the second of three videos on the Internet of Things where we talk about Communication.
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Lecture 24
Internet of Things (IoT)
Part 3 - The downsides of IoT
Video 3 of 3 for this lecture.
Florian Streibelt
IoT, E-Waste, Recycling, Economies of scale, Bugs, Failure, Pets, Mirai
This is the third and last video on IoT, the 'Internet of Things' where we will look at some of the controversial and negative aspects of IoT.
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Lecture 25
Networking at scale
Internet, Protocols
Video 1 of 4 for this lecture.
Prof. Anja Feldmann, PhD
large scale, design for scale, routing, autonomous systems, classful routing, IP CIDR, Fault tolerance, Metcalfe's law,
This video is on how to design a system on the internet that envolves a large number of interconnected entites
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Lecture 25
Indirection
Internet, Protocols
Video 2 of 4 for this lecture.
Prof. Anja Feldmann, PhD
Indirection, Multicast, Mobility, Indirect Routing, Mobile IP
This video explains indirection, or how to reference entities indirectly. We will explain multicast and mobility, and answer thee question of: how to contact a friend that is on the go. We will leearn about mobility vocabulary, routing and specifically mobile IP.
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Lecture 25
Virtualization
Internet, Protocols
Video 3 of 4 for this lecture.
Prof. Anja Feldmann, PhD
Virtualization, Cerf and Khan, Internet Routing, Overlay Networks, Virtual Private Networks (VPN), Tunneling, VLANs
in this video we will talk about the history of virtualization, explain old and new overlay networks, what VPNs and tunneling means and what VlANs are.
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Lecture 25
Internet: The Big Picture
Past, Presence and Future
Video 4 of 4 for this lecture.
Prof. Anja Feldmann, PhD
Internet, Future, Overview, Big Picture, IP, World Domination, KISS, Internet Architecture, Firewalls
This video takes a look at the Internet design as a whole. How did it all start, what have been the ideas and why does it still works (most of the time).
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Lecture 26
Quality of Service (QoS)
Priorities, priorities...
Video 1 of 3 for this lecture.
Balakrishnan Chandrasekaran, PhD
QoS, Quality of service, ToS, service classes, differentiated services, VoIP
This video covers some aspects of traffic priorization. What are some challenges when different applications share the available bandwidth. For example, how can the network help ensure that applications that require low rtt, typically voice and real-time video applications, remain usable while starting a download in the background.
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Lecture 26
Real-Time "Conversational" Applications
RTP and SIP
Video 2 of 3 for this lecture.
Balakrishnan Chandrasekaran, PhD
UDP, RTP, RTCP, SIP, Telephony, VoIP
This video is related to the lecture series on multimedia protocols. We will look at the various protocols used to enable real-time "conversational" applications, for example video telephony, and look at the protocol design and the interplay between the different procols involved.
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Lecture 26
QUIC
Quick UDP Internet Connections
Video 3 of 3 for this lecture.
Balakrishnan Chandrasekaran, PhD
Head of Line blocking, HTTP, UDP, QUIC, protocol design
In this video we again focus on a protocol, that is implemented on top of UDP. We will explore some of the reasons why HTTP via TCP was considered unsuitable and look into the protocol design of QUIC - Qick UDP Internet Connections.
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Lecture 27
Internet Organisation(s)
How the Internet is run
Franziska Lichtblau and Florian Streibelt
Internet Governance, RIR, LIR, RIPE, DNS, NIC, DENIC, IETF, Policies, RFCs, ISOC, ICANN, Internet Freedom, Cyber, IDN, Resources
In this video we will talk about the inofficial 'layer 8' - the humans running and defining what the Internet is. Who is creating Internet standards, how are RFCs written, how it's decided what protocols are 'officially' used on the Internet. This video tries to give an overview on the non-technical part of Internet Operations.
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Lecture 27
Online Social Networks (OSN)
Part I
Video 1 of 2 for this lecture.
Savvas Zannettou, PhD
Online Social Networks, data collection, graph analysis, clustering, timeseries analysis,
This course introduces Online Social Networks (OSN). It covers data collection, and the diffrent techniques used for data analysis
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Lecture 27
Online Social Networks (OSN)
Part II
Video 2 of 2 for this lecture.
Savvas Zannettou, PhD
Online Social Networks, memes, twitter, Reddit, $chan, Gab, perceptual hashing, crawl, know Your Meme (KYM), trolls,
This course introduces the study of memes in Online Social Networks (OSNs). It answers the questions: why? how? who? and where?
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