Networking
Networking Learning Flashcard
Networking Learning Flashcard
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Lernkarten
What is the difference between a host and an end system? List several different types of end systems. Is a Web server an end system?
- host = end system.
- There are two types of hosts: clients and servers.
- A Web server is an end system.
Standards are important for protocols because only when everyone agree on what each and every protocol does, people can create systems and products that interoperate.
List six access technologies. Classify each one as home access, enterprise access, or wide-area wireless access.
- Digital subscriber line (DSL) - home access
- Cable Internet access - home access
- Fiber to the home (FTTH) - home access
- Ethernet - enterprise access
- WiFi - enterprise access
- 3G - wide-area wireless access
- LTE - wide-area wireless access
--Could not understand from reading the text yet--
Users typically have 100 Mbps access to the Ethernet switch, whereas servers may have 1 Gbps or even 10 Gbps access.
Why will two ISPs at the same level of the hierarchy often peer with each other? How does an IXP earn money?
- Two ISPs peer so that they can avoid paying upstream intermediaries.
- An IXP (Internet Exchange Point) earns money by providing a meeting point where multiple ISPs can peer together.
--Could not find from reading the text yet--
What are the five layers in the Internet protocol stack? What are the principal responsibilities of each of these layers?
- Application - Web document request and transfer (HTTP), email (SMTP), transfer of file (FTP), directory service (DNS)
- Transport - transports application-layer messages between application endpoints
- Network - moving network-layer packets known as datagrams from one host to another
- Link - move a packet from one node (host or router) to the next node in the route
- Physical - move the individual bits within a frame from one node to the next.
List five nonproprietary Internet applications and the application-layer protocols that they use.
- The Web - HTTP
- Email - SMTP
- File Transfer - FTP
- Remote terminal access - Telnet
- Streaming media - HTTP
- Directory service - DNS
What is the difference between network architecture and application architecture?
- The network architecture (e.g. the five-layer Internet architecture) is fixed and provides a specific set of services to applications.
- The application architecture is designed by the application developer and dictates how the application is structured over the various end systems. There are two type of network application architecture: client-server and P2P.
For a communication session between a pair of processes, which process is the client and which is the server?
- The process that initiate the communication is the client
- The process that wait to be contacted is the server.
What information is used by a process running on one host to identify a process running on another host?
- IP address to identify the other host
- Port number to identify the process
Suppose you wanted to do a transaction from a remote client to a server as fast as possible. Would you use UDP or TCP? Why?
UDP.
UDP does not include a congestion-control mechanism, so the sending side of UDP can send at high rate.
List the four broad classes of services that a transport protocol can provide. For each of the service classes, indicate if either UDP or TCP (or both) provides such a service.
- Reliable Data Transfer - UDP No, TCP Yes
- Throughput - UDP and TCP No
- Security - UDP No, TCP (with SSL) Yes
- Timing - UDP and TCP No
Recall that TCP can be enhanced with SSL to provide process-to-process security services, including encryption. Does SSL operate at the transport layer or the application layer? If the application developer wants TCP to be enhanced with SSL, what does the developer have to do?
SSL operates at application layer.
If the application developer wants TCP to be enhanced with SSL, he need to include the SSL code in both the client and server side of the application.
A protocol that specifies how hosts acknowledge each other.
Because TCP provides reliable data transfer.
Describe how Web caching can reduce the delay in receiving a requested object.
- Web cache (or proxy server) stores a copy of all objects that client has requested via it.
- When another client requests a similar object, the web cache just send the local copy to ther client via connection between the web cache and the client instead of request again from the server.
Because FTP uses a separate control connection to sends control information in addition of the data connection that sends the data.
It's possible. Type of RR to store the mail server is MX while for web server is A.
