Stallings, Chapter 4
Terms in this set (28)
First operational packet switching network
The place where tele-phone companies terminate customer lines and locate switching equipment to interconnect those lines with other networks.
A group of networks that are part of the Internet and that are under the administrative control of a single entity, such as a company or govern-ment agency.
domain name system (DNS)
A directory lookup service that provides a mapping between the name of a host on the Internet and its numerical address.
Any end system, such as a PC, work-station, or server, that connects to the Internet.
Internet Protocol (IP)
A standardized protocol that executes in hosts and routers to interconnect a number of independent networks.
Internet service provider (ISP)
A com-pany that provides other companies or individuals with access to, or presence on, the Internet.
each packet includes a unique numeric address of the destination host
IP datagram/IP packet
the source host breaks the data to be sent into a sequence of packets
dedicated path of transmission, holds one channel at a time
network access point (NAP)
one of several major Internet interconnection points that serve to tie all the ISPs together.
network service provider (NSP)
A company that provides backbone services to an Internet service provider ( ISP), the company that most Web users use for access to the Internet.
point of presence (POP)
A site that has a collection of telecommunications equipment, usually refers to ISP or telephone company sites. An ISP POP is the edge of the ISP's network; con-nections from users are accepted and authenticated here. An Internet access provider may operate several POPs distributed throughout their area of operation to increase the chance that its subscribers will be able to reach one with a local telephone call.
root name server
13 servers in the top of the server hierarchy. responsible for top level zones
An internetworking device that connects two computer networks. It makes use of an internet protocol and assumes that all attached devices on the networks use the same protocol architecture at the internet layer and above.
Transmission Control Protocol (TCP)
one of the core protocols of the Internet Protocol Suite. TCP is one of the two original components of the suite
World Wide Web (WWW)
A networked, graphically oriented hypermedia system. Information is stored on servers, exchanged between servers and browsers, and displayed on browsers in the form of pages of text and images.
dedicated path of transmission. channels are held until transmission is complete. continuous stream of bits. data rate is guaranteed
A method of transmitting messages through a communications network, in which long messages are subdivided into short packets. Each packet is passed from source to destination through intermediate nodes. At each node, the entire message is received, stored briefly, and then passed on to the next node.
A worldwide internetwork based on TCP/ IP that interconnects thou-sands of public and private networks and millions of users.
domain name space
DNS uses a tree-structured name space to identify resources on the Internet
Conceptually, each node and leaf in the name space tree struc-ture names a set of information ( e. g., IP address, name server for this domain name, etc.) that is contained in resource record ( RRs). The collection of all RRs is organized into a distributed database.
These are server programs that hold information about a portion of the domain name tree structure and the associated RRs.
These are programs that extract information from name servers in response to client requests. A typical client request is for an IP address corre-sponding to a given domain name.
each name server is configured with a subset of the domain name space. a collection of one or more subdomains within a domain, along with associated RR.
Query another name server for the desired result and then send the result back to the resolver.
Return to the resolver the address of the next server ( B) to whom the request should be sent. The resolver then sends out a new DNS request to B.