Application Protocols & DNS-RS Web Hosting

Application Protocol Questions

1. How does the Application level of the TCP/IP model map to the ISO/OSI model?

The application layer of the TCP model maps to the top 3 layers of the OSI/ISO model. On the TCP side, Application layer = Application, Presentation, and Session layers on the OSI side.

2. The primary difference between FTP and TFTP is user authentication. What is meant by the term "user authentication?"

Access control, user authentication is a system that confirms the user is who they say they are by forcing the user to provide credentials proving that they have authorized access to the resource

3. Which protocol is used most often for sending mail between mail servers? SMTP

4. Which mail protocol would you use for receiving mail? IMAP4 or POP3

5. If you are using a conventional browser to surf the Internet, what protocol(s) are you most likely using?

HTTP, HTTPS

6. If you are buying a product on Amazon or checking your bank balance online, what protocol should you be using?

HTTPS

7. Who created SSL?

Netscape for implementing HTTPS into the Navigator web browser

8. What is TLS? Who created it?

Transport Layer Security, a cryptographic security protocol that is based upon SSL. The IETF created the TLS standard based upon Netscape SSL.

9. Name common Voice over IP (VoIP) protocols.

SIP - Session Initiation Protocol, sets up and takes apart calls

RTP - Real Time Transport Protocol, carrier for the actual data packets

MGCP - Media Gateway Control Protocol, controls gateways utilized in VOIP/Telephony communication.

10. Which protocol actually sends your voice across the network? RTP

DNS Protocol Questions

1. What is the difference between a routable and a non-routable protocol?

A routable protocol contains a device address as well as a network address for that device, a non-routable protocol only contains the device address

2. To connect separate routable networks, what hardware device would be appropriate? Switch

3. In TCP/IP, what physical device is called the default gateway? Router

4. What is DNS?

DNS stands for Domain Name System and is the system that allows users to enter a URL into a web browser and connect to the correct server that corresponds to that URL by looking up the URL and returning the correct IP address of the server.

5. Briefly describe the DNS query/response process.

A user enters a URL into their browser where the application resolver looks to see if there is a record for that URL's IP address, if the resolver cannot match the URL to an IP then a packet goes out of the computer to a local name server and looks there. If there still isn't a match it would leave the network and check a root server to see what to do to find the address, the root server will instruct the packet to go to a specific TLD server and the TLD server will tell it to go to a specific name server. After the packet goes to that specific name server it would find the IP address and then return the IP address that matched the URL.

6. What is DHCP (Dynamic Host Control Protocol)?

DHCP is a protocol that automatically configures TCP/IP networking on devices to automatically discover and obtain the correct information to communicate on a network.

7. Briefly describe the DHCP process.

DHCP assigns an open IP address and configuration settings to a client computer that does not have an IP address or the correct configuration and then reports to the DNS where that IP address went.