What are the types of access networks mentioned for connecting end systems to edge routers?
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Residential access networks, institutional access networks (school, company), and mobile access networks.
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What are the types of access networks mentioned for connecting end systems to edge routers?
Residential access networks, institutional access networks (school, company), and mobile access networks.
What is the proposed option for connecting access ISPs?
Connect each access ISP to every other access ISP.
What type of networks are typically used in companies and universities?
Enterprise access networks (Ethernet).
What is the purpose of an Optical Network Terminal (ONT)?
To connect fiber optic networks to home networks.
What is the Internet structure described as?
A network of networks.
What connects each access ISP to a global transit ISP?
Economic agreements between customer and provider ISPs.
What is needed for reliable data transfer in packet switching?
Protocols for reliable data transfer and congestion control.
What does the traceroute program measure?
It measures delay from the source to each router along the end-to-end Internet path towards the destination.
What are the two types of access network configurations mentioned?
Shared or dedicated.
What is the Internet described as in terms of structure?
A network of networks.
What is an example of a human protocol?
A conversation like 'Hi, got the time?'
What does TDM stand for?
Time Division Multiplexing.
What is an important consideration regarding the access network's performance?
The bandwidth (bits per second) of the access network.
What are packets in data communication?
Packets are smaller chunks of data, each of length L bits, created from an application message.
What is the transmission rate denoted by R?
R is the link transmission rate, also known as link capacity or link bandwidth.
What connects access networks to ISPs?
Regional networks.
What can you do with a Slingbox?
Watch and control cable TV remotely.
What is a protocol in the context of networking?
A set of rules governing the exchange of data between devices.
How do human protocols differ from network protocols?
Human protocols involve specific messages and actions taken during communication, while network protocols govern communication between machines.
What is the Internet viewed as in the context of data communication?
A service infrastructure that provides services to applications.
What is an example of a computer network protocol?
TCP connection request and response.
What is a bottleneck link?
The link on the end-to-end path that constrains end-to-end throughput.
What are the transmission rates for 802.11b/g (WiFi)?
11 Mbps for 802.11b and 54 Mbps for 802.11g.
What happens when a packet arrives at a full queue?
The packet is dropped (aka lost).
What is the main difference between FDM and TDM in circuit switching?
FDM (Frequency Division Multiplexing) allocates different frequency bands to users, while TDM (Time Division Multiplexing) allocates time slots to users.
What does R_s represent in the context of end-to-end throughput?
The average end-to-end throughput in bits per second.
What is the Internet structure described as?
A network of networks.
What is packet switching?
A method that uses store-and-forward technique for data transmission.
What is the Internet?
A global network of interconnected computers that communicate using standardized protocols.
In the context of circuit switching, how many users can be accommodated in the example provided?
4 users.
What happens if one global ISP is a viable business?
There will be competitors that must interconnect.
What role does an Ethernet switch play in a network?
It connects end systems within the network.
What is the function of the host in data communication?
The host sends packets of data by taking an application message and breaking it into smaller chunks known as packets.
What does FDM stand for?
Frequency Division Multiplexing.
What are the common transmission rates for Ethernet?
10 Mbps, 100 Mbps, 1 Gbps, and 10 Gbps.
What aspects do protocols define in network communication?
The format, order of messages sent and received, and actions taken on message transmission and receipt.
What are the two main types of hosts in a network?
Clients and servers.
What does L represent in the context of data packets?
L represents the length of each packet in bits.
What does TCP stand for?
Transmission Control Protocol.
What are the components of the network edge?
End systems, access networks, and links.
What causes loss and delay in data communication?
When the packet arrival rate temporarily exceeds the output link capacity.
What is a challenge in providing circuit-like behavior in packet switching?
Bandwidth guarantees are needed for audio/video applications.
What types of services might be supported by an institutional router?
Institutional mail and web servers.
What is the 'nuts and bolts' view of the Internet?
It refers to millions of connected computing devices, including hosts (end systems) and communication links.
In a one-hop transmission example, what are the values of L and R?
L = 7.5 Mbits and R = 1.5 Mbps.
What are the two types of switching discussed in the network core?
Packet switching and circuit switching.
What is a global transit ISP?
An Internet Service Provider that provides connectivity between different networks on a global scale.
What is the typical speed range for wide-area wireless access?
Between 1 and 10 Mbps.
What does 'protocol layers' refer to in networking?
The organization of protocols in layers to facilitate communication.
What do protocol layers and service models refer to?
The organization of network protocols and the services they provide.
What are the main components of networks mentioned?
Hosts, routers, links of various media, applications, protocols, hardware, and software.
What is a key advantage of packet switching?
Great for bursty data and resource sharing.
What does R_c represent in the context of end-to-end throughput?
The capacity of the bottleneck link in bits per second.
What is a disadvantage of packet switching?
Excessive congestion can lead to packet delay and loss.
What is the function of a web-enabled toaster?
It acts as a toaster and a weather forecaster.
What is the focus of Chapter 1 in the EE3009 Data Communication & Networking course?
An introduction to the Internet and its components.
What does the caravan analogy represent in data communication?
Cars represent bits, and the caravan represents packets.
What does CMTS stand for?
Cable Modem Termination System.
What are the main components discussed in the network edge section?
End systems, access networks, and links.
What significant protocol was deployed in 1983?
TCP/IP.
What is a physical link in data communication?
It refers to what lies between the transmitter and receiver.
What are the five layers of the networking model mentioned?
Application, Transport, Network, Link, Physical.
What is throughput in data communication?
The rate (bits/time unit) at which bits are transferred between sender and receiver.
What types of ISPs are mentioned?
Residential, company, and university ISPs.
What does nodal processing delay (d_proc) involve?
Checking bit errors and determining the output link.
What is the distance between the two toll booths in the caravan analogy?
100 km.
What is the main characteristic of circuit switching?
End-to-end resources are allocated and reserved for a call between source and destination.
What types of communication links are mentioned?
Fiber, copper, radio, and satellite.
What does the protocol layers section cover?
Service models and the structure of protocols.
What is the Internet often referred to as?
A 'network of networks'.
What is the role of a buffer in data communication?
It serves as a waiting area for packets before they are transmitted.
What is the Internet structure described as?
A network of networks.
What is the Internet structure described as?
A network of networks.
What is a key challenge in connecting millions of access ISPs?
How to connect them together.
What does the term 'protocol layers' refer to in networking?
The structured organization of various network components and their interactions.
What types of services does the Internet provide?
Web, VoIP, email, games, e-commerce, social networks, etc.
What can occur if the memory (buffer) fills up in a packet switching scenario?
Packets can be dropped (lost).
How many hosts are estimated to be on the Internet?
Approximately 750 million hosts.
What is the Internet?
A global network of interconnected computers that communicate using standardized protocols.
What is the transmission rate of link A in the given scenario?
100 Mb/s.
What is the primary component used in a cable network for data communication?
Cable modem.
What happens when R_s is greater than R_c?
The average end-to-end throughput is constrained by R_c.
What is a notable difference between the ISO/OSI model and the Internet stack?
The Internet stack is missing the presentation and session layers.
What trend is observed in broadband access?
Aggressive deployment of broadband access.
When was the telegraph network first used?
About 1844.
What is the maximum upstream transmission rate in an HFC network?
2 Mbps.
What is the purpose of encapsulation in networking?
To wrap data with protocol information at each layer.
How long does it take for the entire caravan to pass through the toll booth?
120 seconds (12 seconds per car for 10 cars).
What is the role of the DSLAM in a DSL network?
It connects multiple DSL lines to the Internet and manages data transmission.
What is a segment in the context of data communication?
A unit of data at the Transport layer.
What is average throughput?
The rate over a longer period of time.
What happens to the packets sent by the traceroute program?
They reach router i on the path towards the destination, and the router returns them to the sender.
What may happen to a lost packet?
It may be retransmitted by the previous node, by the source end system, or not at all.
What is the scalability issue with connecting each access ISP directly?
It results in O(N^2) connections.
What is the role of Internet Service Providers (ISPs) in the Internet structure?
ISPs must be interconnected to provide access.
How is packet transmission delay calculated?
Packet transmission delay is calculated as L (bits) divided by R (bits/sec).
What is the role of access networks in the Internet structure?
They connect end users to the Internet.
What does 'access net' refer to in the context of the Internet?
It refers to the networks that provide access to the Internet for users.
What role do content provider networks play in the Internet structure?
They run their own networks to bring services and content close to end users.
What is the first topic covered in the EE3009 Data Comm. & Networking course?
What is the Internet?
What is the role of physical media in data communication?
It allows bits to propagate between transmitter/receiver pairs.
What are the two types of physical media mentioned?
Coaxial cable and fiber optic cable.
What does the network edge include?
End systems, access networks, and links.
What are the components of the network edge?
End systems, access networks, and links.
What do ISPs and IXPs represent in the Internet structure?
ISPs are Internet Service Providers, and IXPs are Internet Exchange Points.
What device is used to split signals in a cable network?
Splitter.
What theory did Kleinrock demonstrate in 1961?
Queueing theory shows the effectiveness of packet-switching.
What type of communication do internet phones facilitate?
Voice communication over the internet.
What is the role of the queue in packet switching?
To hold packets waiting for output link transmission.
What does 'R' represent in the context of throughput?
The backbone bottleneck link capacity in bits/sec.
What are 'tier-1' commercial ISPs?
Large networks that provide national and international coverage, such as Level 3, Sprint, AT&T, and NTT.
What does ISO stand for?
International Organization for Standards.
Why is layering important in data communication systems?
It helps in dealing with complex systems by providing an explicit structure for identification and relationships of system components.
What is covered under protocol layers in the course?
Service models.
What does transmission rate refer to?
Bandwidth.
What does the course introduce regarding Internet structure?
An overview of the Internet's structure.
What is the Internet structure described as?
A network of networks.
What does ONT stand for in the context of fiber to the home?
Optical Network Terminal.
What is the purpose of organizing the structure of a network?
To facilitate discussion and understanding of networks.
What type of network is used for data and TV transmission over shared cables?
Cable distribution network.
What is the focus of Chapter 1 in the EE3009 Data Comm. & Networking course?
An introduction to the Internet and networking concepts.
What device is used to connect a home to a cable network?
Cable modem.
Where are servers often located?
In data centers.
What does the Internet provide to applications?
A programming interface with hooks for sending and receiving application programs.
What do peering links facilitate?
Direct traffic exchange between ISPs.
What is the speed at which cars (bits) propagate in the analogy?
100 km/hr.
How is the Internet's service options analogous?
It is analogous to postal services.
What two types of switching are covered in the network core section?
Packet switching and circuit switching.
What protocol was defined in 1982 for email communication?
SMTP (Simple Mail Transfer Protocol).
What is the Internet structure described as?
A network of networks.
What occurs if there are no free buffers in a router?
Arriving packets are dropped, resulting in loss.
What does HFC stand for in the context of coaxial cable?
Hybrid Fiber-Coaxial.
What key performance metrics are discussed in relation to networks?
Delay, loss, and throughput.
What is the approximate propagation speed in the medium?
~2 x 10^8 m/sec.
What does the network core consist of?
A mesh of interconnected routers.
What does FTTH stand for?
Fiber to the Home.
How are resources allocated in circuit switching?
Resources are dedicated and not shared among calls.
What do protocol layers and service models refer to?
The organization of network protocols and the services they provide.
What is a key advantage of fiber optic cable in terms of speed?
It allows high-speed point-to-point transmission, with rates of tens to hundreds of Gbps.
What significant development in TCP occurred in 1988?
TCP congestion control.
What is the role of packet switches in networking?
They forward packets (chunks of data).
What does La/R > 1 imply about the workload?
More 'work' is arriving than can be serviced, leading to infinite average delay.
What is a queue in the context of data communication?
A buffer that has finite capacity preceding a link.
What is a protocol in the context of networking?
A set of rules governing communication activities among network entities.
What is the Internet structure described as?
A network of networks.
What is an example of a fun internet appliance mentioned?
IP picture frame.
What is an Internet Exchange Point (IXP)?
A facility where ISPs connect and exchange traffic.
What type of access network is mentioned in the slide?
Fiber to the home.
What is the typical range of wireless LANs?
Within a building, approximately 100 feet.
What happens if one global ISP is a viable business?
There will be competitors.
What role do IXPs play in the Internet structure?
They connect different ISPs.
How long does it take to transmit an L-bit packet into a link at R bps?
L / R seconds.
What types of devices contribute to the number of hosts on the Internet?
Smartphones and tablets.
What is the formula for transmission delay (d_trans)?
d_trans = L/R, where L is packet length in bits and R is link bandwidth in bps.
What is packet-switching?
A method where hosts break application-layer messages into packets for transmission.
What does 'L' stand for in data communication?
Packet length (bits).
What is the purpose of an institutional link to an ISP?
To connect the institution to the Internet.
What are hosts in the context of the Internet?
Hosts are end systems running network applications.
What is the purpose of regional networks in the Internet structure?
To connect various access networks and facilitate communication.
What was defined in 1983 for name-to-IP address translation?
DNS (Domain Name System).
What type of switching was used in telegraph networks?
Message switching.
What unique feature does an internet refrigerator have?
It can connect to the internet for various functionalities.
How many cars are in the caravan in the analogy?
Ten cars.
What is the role of the application layer in the Internet protocol stack?
Supporting network applications such as FTP, SMTP, and HTTP.
What drives the evolution of the Internet structure?
Economics and national policies.
What does OSI stand for?
Open System Interconnection.
What is GPON?
Gigabit Passive Optical Networks.
What types of data can be transmitted over a cable network?
Video and data.
What type of switching is associated with telephone networks?
Circuit switching.
What connects an end system to a router in a wireless access network?
A base station, also known as an access point.
How do end systems typically connect in an Ethernet network?
They connect into an Ethernet switch.
What governs all communication activity on the Internet?
Protocols.
What are the components discussed under 'network edge'?
End systems, access networks, and links.
What is the Internet described as?
A network of networks.
What is the primary function of routers in a network?
To forward packets from one router to the next across links.
What does 'R' represent in the context of data communication?
Link bandwidth (bps).
What are the two main types of switching in the network core?
Packet switching and circuit switching.
What does the Tweet-a-watt device monitor?
Energy use.
What are the characteristics of coaxial cable?
It has two concentric copper conductors, is bidirectional, and supports broadband with multiple channels.
How long does it take to service a car at the toll booth?
12 seconds.
What does DSL stand for in networking?
Digital Subscriber Line.
If presentation and session services are needed in the Internet stack, where must they be implemented?
In the application layer.
What is the function of a cable headend in a cable network?
It serves as the central point for signal distribution.
What is the purpose of the traceroute program?
To provide delay measurement and visualize the route taken by packets to the destination.
What are unguided media?
Signals propagate freely, such as in radio communications.
What does La/R ~ 0 indicate about average queueing delay?
Average queueing delay is small.
What are the two types of switching discussed in the course?
Packet-switching and circuit-switching.
What are the four sources of packet delay?
Propagation delay, nodal delay, processing delay, and queueing delay.
What historical aspect is included in the course roadmap?
The history of networking technologies.
What protocols are associated with the transport layer?
TCP and UDP.
How long does it take for the last car to propagate from the first to the second toll booth?
1 hour.
How is total nodal delay (d_nodal) calculated?
d_nodal = d_proc + d_queue + d_trans + d_prop.
What is the main function of the network layer?
Routing of datagrams from source to destination.
What was the evolution of transmission in telephone networks?
From analog transmission to digital transmission.
What key technologies were developed by Berners-Lee in the early 1990s?
HTML and HTTP.
What do protocol layers and service models refer to?
The organization of network protocols and the services they provide.
What happens when the internal function of a layer changes?
It does not affect the rest of the system.
What devices are included as end systems?
Smartphones, PCs, servers, and wireless laptops.
What will be covered in more depth later in the course?
Detailed aspects of networking.
What period does the history of internetworking cover in this context?
1972 - 1980.
What happens when the arrival rate to a link exceeds its transmission rate?
Packets will queue and wait to be transmitted on the link.
What do ISPs stand for?
Internet Service Providers.
What does the presentation layer of the ISO/OSI model allow applications to do?
Interpret the meaning of data, including encryption and compression.
What is the speed of the cars in the caravan analogy?
1000 km/hr.
What role do global ISPs play in the Internet structure?
They facilitate connections between access ISPs.
What functions does the session layer provide?
Synchronization, checkpointing, and recovery of data exchange.
How long does it take for a toll booth to service a car in the analogy?
One minute.
How do end systems connect to the Internet?
Via access ISPs (Internet Service Providers).
What are the four sources of packet delay?
Nodal processing, queueing, transmission, and propagation.
Will cars arrive at the second toll booth before all cars are serviced at the first booth?
Yes, after 7 minutes, the first car arrives at the second booth while three cars are still at the first booth.
What does the sender do after sending packets in a traceroute?
The sender times the interval between transmission and reply from the router.
What are the two main types of switching in the network core?
Packet switching and circuit switching.
What is the one-hop transmission delay for the given values of L and R?
5 seconds.
What is instantaneous throughput?
The rate at a given point in time.
Why must access ISPs be interconnected?
So that any two hosts can send packets to each other.
What is the typical duration of nodal processing delay?
Typically less than a millisecond.
What type of media does radio communication use?
Electromagnetic spectrum.
In practice, which is often the bottleneck in throughput scenarios?
Rc or Rs.
What significant network was conceived in 1967?
ARPAnet by the Advanced Research Projects Agency.
What percentage of the time is each user active?
10%.
What do protocols control in the context of the Internet?
The sending and receiving of messages.
What is the formula for nodal delay (d_nodal)?
d_nodal = d_proc + d_queue + d_trans + d_prop.
What does a '*' indicate in a traceroute output?
It means no response (probe lost, router not replying).
Name an example of a protocol used on the Internet.
TCP, IP, HTTP, Skype, or 802.11.
What is the maximum speed of Category 6 twisted pair cables?
10 Gbps.
What does RFC stand for?
Request for Comments.
What is the typical speed of wireless access points in a home network?
54 Mbps.
How does the history of circuit-switching networks compare to the Internet?
Circuit-switching networks have a much longer history than the Internet.
What are the cellular network generations mentioned?
3G, 4G, and 5G.
What does the term 'trans-oceanic link' refer to in the context of networking?
It refers to connections that span across oceans, facilitating international data transfer.
What is a routing algorithm?
A method used to determine the best path for data packets to travel across a network.
What networking technology was introduced at Xerox PARC in 1976?
Ethernet.
What does 'store and forward' mean in packet switching?
The entire packet must arrive at the router before it can be transmitted on the next link.
Why are networks considered complex?
Because they consist of many different components and interactions.
What happens when R_s is less than R_c?
The average end-to-end throughput is limited by R_s.
Can you name some examples of content provider networks?
Google, Microsoft, Akamai.
Name three ISPs mentioned in the text.
ISP A, ISP B, ISP C.
What is an access ISP?
An Internet Service Provider that connects users to the Internet.
What type of wireless access is provided by telco operators?
Wide-area wireless access.
What key performance metrics are discussed in the context of networks?
Delay, loss, and throughput.
What factors are considered in network performance?
Delay, loss, and throughput.
What are the different types of networks mentioned in relation to the Internet?
Mobile network, global ISP, regional ISP, home network, institutional network.
What is the data rate of the link discussed in the example?
1 Mb/s.
What is the main focus of the EE3009 Data Communication & Networking course?
To provide an overview of networking concepts.
What was the focus of Baran's work in 1964?
Packet-switching in military networks.
What technologies are associated with wide-area wireless access?
3G, 4G, and LTE.
What aspect of networking does 'history' cover in this chapter?
The evolution and development of networking technologies.
What is a Tier-1 ISP?
An Internet Service Provider that can reach every other network on the Internet without purchasing IP transit or paying for peering, e.g., Sprint.
What role do content provider networks, like Google, play in the Internet structure?
They are private networks that connect data centers to the Internet, often bypassing tier-1 and regional ISPs.
What is queueing delay (d_queue)?
The time waiting at the output link for transmission, depending on the congestion level of the router.
What significant event occurred in the early 1990s regarding ARPAnet?
ARPAnet was decommissioned.
How many connections are sharing the backbone bottleneck link in the given scenario?
10 connections.
What type of existing infrastructure does DSL use?
Existing telephone lines.
How does modularization benefit system maintenance?
It eases maintenance and updating of the system.
What are the key performance metrics in networks?
Delay, loss, and throughput.
What is the average delay from cs-gw (128.119.240.254) in the traceroute example?
1 ms.
Where is circuit switching commonly used?
In traditional telephone networks.
What are the typical speeds for LAN radio links like WiFi?
11 Mbps and 54 Mbps.
What type of switching is used in the Internet?
Packet switching.
Which university is mentioned in the introduction?
City University of Hong Kong.
What is the purpose of routing in networking?
Determining the source-destination route taken by packets.
What does a local forwarding table contain?
Information used to forward packets based on header values.
What are the key principles of Cerf and Kahn's internetworking?
Minimalism, autonomy, best effort service model, stateless routers, decentralized control.
What type of information can be requested using a protocol?
Data such as a file or a webpage (e.g., http://www.awl.com/kurose-ross).
What types of communication links are included in access networks?
Wired and wireless.
What is the maximum downstream transmission rate in an HFC network?
Up to 30 Mbps.
What is the transmission rate of link B in the given scenario?
1.5 Mb/s.
What is the formula for per-connection end-to-end throughput in an Internet scenario with 10 connections?
min(Rc, Rs, R/10).
What is the formula for propagation delay (d_prop)?
d_prop = d/s, where d is the length of the physical link and s is the propagation speed in the medium.
How are packets transmitted in a packet-switched network?
Each packet is transmitted at full link capacity.
What is the formula for traffic intensity?
Traffic intensity = La/R.
What are the different types of networks mentioned in the network core?
Mobile network, global ISP, regional ISP, home network, and institutional network.
How does the cable network differ from DSL in terms of access?
Cable shares access to the headend, while DSL has dedicated access to the central office.
How much bandwidth does each user require when active?
100 kb/s.
What is an example of an online social network?
Facebook.
What is the focus of the history section in networking?
The evolution and development of networking technologies.
How does DSL transmit voice and data?
At different frequencies over a dedicated line to the central office.
What is the purpose of the traceroute command?
To measure the delays and routes taken by packets across the Internet.
What does the server send to the client?
A file of F bits.
What is the nature of the resulting network of networks?
It is very complex.
How many users can be supported in circuit switching in this example?
10 users.
What does 'Rs' refer to in the context of the throughput scenario?
The rate of each connection.
What is the typical upstream transmission rate for DSL?
Typically less than 1 Mbps, with a maximum of 2.5 Mbps.
What is the significance of protocols in networking?
Protocols define the rules for communication between devices.
Which node has the highest average delay in the provided traceroute?
fantasia.eurecom.fr (193.55.113.142) with 132 ms.
What does the course aim to provide in terms of networking?
Context, overview, and a 'feel' of networking.
What trend emerged in the late 1990s regarding the Web?
Commercialization of the Web.
What new applications became popular in the late 1990s to 2000s?
Instant messaging and P2P file sharing.
What were some proprietary architectures developed in the late 1970s?
DECnet, SNA, XNA.
What two types of switching are covered under 'network core'?
Packet switching and circuit switching.
How many packets does the traceroute program send to each router?
Three packets.
What happens to packets when they queue in router buffers?
They wait for their turn to be transmitted, causing delay.
What is the human analogy for reserved resources in circuit switching?
Reserved resources can be compared to circuit switching, while on-demand allocation is like packet switching.
What is the role of the network core?
To interconnect routers and form a network of networks.
What are guided media?
Signals propagate in solid media such as copper, fiber, and coaxial cables.
What key performance metrics are discussed in relation to networks?
Delay, loss, and throughput.
What has increased the availability of high-speed Internet?
Increasing ubiquity of high-speed wireless access.
What is the Internet?
A global network of interconnected computers that communicate using standardized protocols.
What is the relationship between packet arrival rate and output link capacity?
If the arrival rate exceeds the capacity, packets will queue and cause delays.
What is the main component of fiber optic cable?
Glass fiber carrying light pulses.
Which protocol was defined in 1985 for file transfer?
FTP (File Transfer Protocol).
When was the Bell Telephone Company founded?
In 1877.
What is the purpose of the access network in a home setup?
To connect the home network to/from the headend or central office.
What is a key characteristic of radio communication?
It has no physical 'wire'.
What is the title of the book referenced in the introduction?
Computer Networking: A Top Down Approach, 7th edition.
When did the first ARPAnet node become operational?
In 1969.
What does CO stand for in networking?
Central Office.
In circuit switching, what type of performance is guaranteed?
Circuit-like performance is guaranteed.
What devices are mentioned in the context of networking?
Router and Switch.
What is the link capacity denoted as R_c?
The capacity of the client's link in bits/sec.
What does the link layer handle?
Data transfer between neighboring network elements.
What are the two key functions of the network core?
Forwarding and routing.
What applications are associated with the Internet?
Computer applications.
What is the significance of performing traceroutes from exotic countries?
To analyze the routing paths and delays from different geographical locations.
What are the key performance metrics in networks?
Delay, loss, and throughput.
What is the formula for end-to-end delay in packet switching?
End-to-end delay = 2L / R (assuming zero propagation delay).
What technology allows different channels to be transmitted in different frequency bands?
Frequency division multiplexing.
What are the components of the network edge?
End systems, access networks, and links.
What is a twisted pair (TP) cable?
It consists of two insulated copper wires.
What does a layered reference model facilitate?
It facilitates discussion about the system's architecture.
What historical aspect is included in the course roadmap?
The history of networking technologies.
What is the function of IXPs in the Internet structure?
They facilitate the exchange of Internet traffic between different ISPs.
What is a frame in networking?
A unit of data at the Link layer.
What is the role of a Tier-1 ISP in data communication?
To connect to/from customers and peer with other networks to/from the backbone.
What is the relationship between access ISPs and regional ISPs?
Access ISPs connect end users to the Internet, while regional ISPs provide broader coverage and connect to tier-1 ISPs.
What is a key advantage of changing a layer's implementation?
The change is transparent to the rest of the system.
What types of networks are mentioned in the document?
Global ISP, regional ISP, home network, institutional network.
What is the role of the IETF?
Internet Engineering Task Force.
How are wireless devices often integrated in home networks?
They are often combined in a single box with other networking devices.
What does forwarding in networking refer to?
Moving packets from a router's input to the appropriate router output.
What is the end-to-end delay for satellite communication?
270 msec.
What significant network was established in Hawaii in 1970?
ALOHA net satellite network.
What is the total time until the caravan is lined up before the second toll booth?
62 minutes.
What does HFC stand for in networking?
Hybrid Fiber Coax.
What happens when La/R > 1?
Average queueing delay becomes large.
What aspects of network performance are covered in the course?
Loss, delay, and throughput.
What are the two main types of switching in the network core?
Packet switching and circuit switching.
What devices are commonly used in a home access network?
Cable or DSL modem, router, firewall, and NAT.
What type of services are run in the cloud by enterprises and universities?
E-commerce and other services (e.g., Amazon EC2).
What major events occurred in 1972 related to ARPAnet?
Public demo, introduction of NCP (Network Control Protocol), first e-mail program, and ARPAnet had 15 nodes.
How many hosts were connected to the confederation of networks by 1990?
100,000 hosts.
What is the typical downstream transmission rate for DSL?
Typically less than 10 Mbps, with a maximum of 24 Mbps.
What department is associated with the introduction slide?
Department of Electrical Engineering.
What is the average delay to the node 62.40.103.253?
Approximately 106 ms.
What does the DSL access multiplexer do?
It combines multiple DSL connections for efficient data transmission.
What are the two main factors contributing to delays in packet transmission?
Queueing of packets and the time taken for packet transmission.
What is a datagram?
A unit of data at the Network layer.
What does POP stand for in networking?
Point of Presence.
What does the history section cover in data communication and networking?
The evolution and development of networking technologies over time.
What are the effects of the propagation environment on radio signals?
Reflection, obstruction by objects, and interference.
What were some of the new national networks in the US during this period?
Csnet, BITnet, NSFnet, Minitel.
What approach is suggested to describe the current Internet structure?
A stepwise approach.
What is an example of a terrestrial microwave channel speed?
Up to 45 Mbps.
What technology is associated with mobile communications?
Circuit switching and digital transmission.
What characterized the period from 1980 to 1990 in networking?
New protocols and a proliferation of networks.
What device is used to separate voice and data signals in a DSL setup?
A DSL modem splitter.
What does the history section cover in networking?
The evolution and development of networking technologies.
What was the estimated number of hosts and users by the late 1990s?
Approximately 50 million hosts and over 100 million users.
What is the significance of the destination address in a packet's header?
It is used to determine the output link for forwarding the packet.
What is the role of links in packet-switching?
Links connect routers and facilitate the forwarding of packets from source to destination.
Which service providers create their own networks to bypass the Internet?
Google and Microsoft.
What happens to circuit segments in circuit switching when not in use?
They remain idle and are not shared with other calls.
What is the maximum speed of Category 5 twisted pair cables?
100 Mbps to 1 Gbps Ethernet.
What happened in 1991 concerning NSFnet?
NSF lifted restrictions on commercial use of NSFnet.
Who are the authors of the book mentioned?
Jim Kurose and Keith Ross.
How many users can be supported in packet switching in this example?
35 users.
Which publisher released the book 'Computer Networking: A Top Down Approach'?
Pearson.
What is the probability that more than 10 users are active at the same time in packet switching?
Less than 0.0004.
What analogy is used to describe the data transfer in the context of throughput?
Bits are sent as fluid into a pipe that can carry fluid at a certain rate.
What are some examples of protocols in the link layer?
Ethernet, 802.11 (WiFi), and PPP.
What is the typical speed range for satellite communication?
Kbps to 45 Mbps.
What was the status of backbone links in the 1990s?
Running at Gbps.
What was a precursor to ATM introduced in the late 1970s?
Switching fixed length packets.
What contributes to the low error rate in fiber optic cables?
Repeaters spaced far apart and immunity to electromagnetic noise.
What is the link capacity denoted as R_s?
The capacity of the server's link in bits/sec.
What is the typical speed of wired Ethernet in a home network?
100 Mbps.
What does 'Rc' refer to in the context of the throughput scenario?
The capacity of the bottleneck link.
What was the significance of Mosaic in 1994?
It was one of the first web browsers, later leading to Netscape.
What is a significant concern for networks today?
Security and networks under attack.
What are the different types of networks mentioned in the 'nuts and bolts' view of the Internet?
Mobile network, global ISP, regional ISP, home network, institutional network.
What is the focus of the physical layer in the Internet protocol stack?
Transmission of bits 'on the wire'.
What are the two types of satellite orbits mentioned?
Geosynchronous and low altitude.
How many nodes did ARPAnet have by 1979?
200 nodes.
What are examples of packet switches?
Routers and switches.
Which protocols are used in the network layer?
IP and routing protocols.
What period does 1961-1972 cover in networking history?
Early packet-switching principles.
What advantage does packet switching have over circuit switching?
Packet switching allows more users to use the network.
What happens if more than 35 users try to use the network?
The example does not specify, but it implies potential issues with capacity.
Who developed the architecture for interconnecting networks in 1974?
Cerf and Kahn.
