Network Applications: 3yad

What is the purpose of including port numbers along with IP addresses in network identifiers?

To distinguish between different processes running on the same host (correct)
To ensure efficient routing of packets across the internet
To provide additional security by obfuscating the true destination
To enable load balancing across multiple servers with the same IP address

What does the term 'public-domain protocol' refer to in the context of application layer protocols?

Protocols that are defined in publicly available standards (RFCs) for interoperability (correct)
Protocols that are primarily used for public-facing services on the internet
Protocols that are open-source and can be freely modified by anyone
Protocols that are designed for use in public networks, as opposed to private networks

Which of the following is NOT a responsibility of an application layer protocol?

Defining the types of messages exchanged between processes
Determining the order in which messages are transmitted (correct)
Specifying the syntax and semantics of messages
Establishing the rules for when and how processes send and respond to messages

In the example provided, what is the port number associated with the mail server?

25 (C) Signup and view all the answers

Which of the following statements about proprietary protocols is true?

Their specifications are typically kept private and not shared openly (C) Signup and view all the answers

What is the main advantage of the client-server architecture over pure P2P architecture?

Always-on server for coordination (B) Signup and view all the answers

Which aspect makes pure P2P architectures highly scalable but difficult to manage?

Intermittent connections of peers (B) Signup and view all the answers

What distinguishes a hybrid architecture from both client-server and P2P architectures?

It combines features of both client-server and P2P models (B) Signup and view all the answers

Why do network-core devices not need to run user applications according to the text?

To allow for rapid development of end-system applications (C) Signup and view all the answers

What allows for writing programs that run on different end systems and communicate over a network?

Socket API (D) Signup and view all the answers

What is a key characteristic of peers in a pure P2P architecture?

They may change IP addresses and have intermittent connections (D) Signup and view all the answers

Which network application protocol allows for emails to be sent and received?

SMTP (B) Signup and view all the answers

What is the primary function of DNS in the context of network applications?

Resolving domain names to IP addresses (C) Signup and view all the answers

What type of program is described as 'program running within a host'?

Process program (C) Signup and view all the answers

What is the primary purpose of the Domain Name System (DNS)?

To translate between hostnames and IP addresses in a distributed manner (B) Signup and view all the answers

Why is the DNS implemented in a hierarchical and distributed manner, rather than a centralized approach?

All of the above (D) Signup and view all the answers

When a client wants to resolve the IP address for www.amazon.com, what is the typical sequence of queries in the DNS hierarchy?

Client queries the root server, then the com server, then the amazon.com server (B) Signup and view all the answers

What is the purpose of having root name servers in the DNS hierarchy?

To store and manage the top-level domain (TLD) information (B) Signup and view all the answers

Which of the following is NOT one of the listed root name server locations provided in the text?

Google, Mountain View, CA (C) Signup and view all the answers

What is the purpose of host aliasing in the DNS?

All of the above (D) Signup and view all the answers

In a nonpersistent HTTP connection, what happens after the server sends the requested object to the client?

The server closes the TCP connection. (A) Signup and view all the answers

What is the purpose of maintaining the past history or state in a client-server application?

To ensure consistent views of the state between the client and server in case of crashes. (A) Signup and view all the answers

In the context of nonpersistent HTTP, what is the significance of the round-trip time (RTT)?

It represents the time required for a small packet to travel from the client to the server and back. (C) Signup and view all the answers

What is the main difference between nonpersistent and persistent HTTP connections?

Nonpersistent HTTP connections can only transfer one object, while persistent connections can transfer multiple objects. (C) Signup and view all the answers

In the context of nonpersistent HTTP, what is the purpose of the client initiating a TCP connection to the server on port 80?

To establish a connection for transferring the requested object. (D) Signup and view all the answers

What is the role of the HTTP server in a nonpersistent HTTP connection?

The server waits for a TCP connection on port 80, accepts the connection, receives the request message, forms a response message containing the requested object, and sends the message through its socket. (B) Signup and view all the answers

In the server-client approach for file distribution, the time taken to distribute a file of size F to N clients is:

$\max{NF/u_s, F/\min(d_i)}$ (C) Signup and view all the answers

In the P2P approach for file distribution, the minimum possible time to distribute a file of size F to N clients is:

$\max{F/u_s, F/\min(d_i), NF/(u_s + \sum_{i=1}^{N} u_i)}$ (D) Signup and view all the answers

In the example comparing server-client and P2P approaches, if the client upload rate is u, the file size is F such that F/u = 1 hour, the server upload rate is 10u, and the minimum download rate is greater than or equal to the server upload rate, what is the minimum distribution time for N=20 clients?

2 hours (D) Signup and view all the answers

In the BitTorrent protocol, what is the primary role of the tracker?

To track the peers participating in the torrent and share their list (A) Signup and view all the answers

In the context of file distribution, what does the term 'torrent' refer to in the BitTorrent protocol?

The group of peers exchanging chunks of the file (A) Signup and view all the answers

Which of the following statements about the BitTorrent protocol is true?

The file being distributed is divided into fixed-size chunks of 256 KB. (C) Signup and view all the answers