CS 6250 Exam 1 : (Notes, Quiz, Practice Questions) UPDATED ACTUAL
QUESTIONS AND CORRECT ANSWERS
Why study Computer Networks? - Internet Growth
- Networks play an Instrumental Role in our Society
- Playground for interdisciplinary research innovations
, JCR Licklider - Led Defense Advanced Research Project Agency (DARPA)
- Proposed the Galactic Network 1962
- First to foresee modern computing
Lawrence G. Roberts - Created ARPANET
- first connected two computers using a low-speed dial up telephone line
ARPANET A computer network developed by the Advanced Research Project Agency (now
the Defense Advance Research Projects Agency) in the 1960s and 1970s as a
means of communication between research laboratories and universities.
ARPANET was the predecessor to the Internet.
Network Control Protocol (NCP) - Used by ARPANET in the early 1970s to route messages in its experimental wide
area network
- move made from time-shared to packet switching
Open Architecture Networking - a process in which networks with fixed standard interfaces would be
interconnected by open "gateways"
- allows computers and networks all over the world to communicate regardless of
what hardware or software components
NCP transformed into... TCP/IP
Domain Name System (DNS) Internet service that translates domain names into IP addresses.
Advantages of Layered Network Stack - Scalability
- Modularity
- Flexibility to add/delete components (can be cost effective)
Disadvantages of Layered Network Stack - some layers depend on others (can violate independence principle)
- one layer can duplicate lower layer functionalities (ex error recovery)
- overhead caused by the abstraction between layers
OSI / TCP/IP: Application - the TCP/IP Application Layer combines the application, presentation, and
session layers of the OSI model
OSI Application Layer - The seventh layer of the OSI Model which provides services directly to the user
and allows the user to use the network
Application Layer (packet of Information) Message
Application Layer Service, Interface, Protocols Whatever you want, whatever you want, Whatever you want: HTTP (web) (1.) Utility
(DNS, SNMP, DHCP (2.) Messaging protocols (SMTP email) (3.) Data Transfer
protocols (NFS, FTP) (4.) Interactive protocols (Telnet)
QUESTIONS AND CORRECT ANSWERS
Why study Computer Networks? - Internet Growth
- Networks play an Instrumental Role in our Society
- Playground for interdisciplinary research innovations
, JCR Licklider - Led Defense Advanced Research Project Agency (DARPA)
- Proposed the Galactic Network 1962
- First to foresee modern computing
Lawrence G. Roberts - Created ARPANET
- first connected two computers using a low-speed dial up telephone line
ARPANET A computer network developed by the Advanced Research Project Agency (now
the Defense Advance Research Projects Agency) in the 1960s and 1970s as a
means of communication between research laboratories and universities.
ARPANET was the predecessor to the Internet.
Network Control Protocol (NCP) - Used by ARPANET in the early 1970s to route messages in its experimental wide
area network
- move made from time-shared to packet switching
Open Architecture Networking - a process in which networks with fixed standard interfaces would be
interconnected by open "gateways"
- allows computers and networks all over the world to communicate regardless of
what hardware or software components
NCP transformed into... TCP/IP
Domain Name System (DNS) Internet service that translates domain names into IP addresses.
Advantages of Layered Network Stack - Scalability
- Modularity
- Flexibility to add/delete components (can be cost effective)
Disadvantages of Layered Network Stack - some layers depend on others (can violate independence principle)
- one layer can duplicate lower layer functionalities (ex error recovery)
- overhead caused by the abstraction between layers
OSI / TCP/IP: Application - the TCP/IP Application Layer combines the application, presentation, and
session layers of the OSI model
OSI Application Layer - The seventh layer of the OSI Model which provides services directly to the user
and allows the user to use the network
Application Layer (packet of Information) Message
Application Layer Service, Interface, Protocols Whatever you want, whatever you want, Whatever you want: HTTP (web) (1.) Utility
(DNS, SNMP, DHCP (2.) Messaging protocols (SMTP email) (3.) Data Transfer
protocols (NFS, FTP) (4.) Interactive protocols (Telnet)
