Module 11 The Client Server Relationship flashcards

Server

Host running a software application that provides information/services to other hosts connected to the internet. Ex. web server

Three common types of server software

Email, web, file

Email

runs ____ server software. Clients use mail client software, such as Microsoft Outlook, to access ___ on the server.

Web

runs ___server software. Clients use browser software, such as Windows Internet Explorer, to access ___ pages on the server.

File

stores corporate and user ___ in a central location. The client devices access these ___ with client software such as the Windows File Explorer.

Client/server systems

Client sends a request to a srever, server carrys out a function like sending a requested document. Ex. combination of web browser/web server.

Server farm

where other servers are in part of the same network

Data center

facility used to house computer systems and associated components, can occupy on room or entire building, expensive to build/maintain, only large organizations use privately built ones, smaller organizations reduce the cost by leasing

Uniform Resource Name (URN)

identifies only the namespace of the resource (web page, document, image, etc.) without reference to the protocol.

Uniform resource locator

defines the network location of a specific resource on the network. HTTP or HTTPS

Protocol/scheme

HTTPS or other protocols such as FTP, SFTP, mailto, and NNTP

Hostname

www.example.com

Path and file name

/author/book.html

Fragment

#page 155

Application Layer protocol

HTTP governs the way that a web server and a web client interacts, it defines the format of the requests and responses exchanged between the client and the server, relies on other protocols to govern how the messages are transported between client/server.

Transport Layer Protocol

Transmission Control Protocol ensures that IP packets are sent reliably and any missing packets are resent, provides proper ordering of packets received out of order

Internetwork Layer Protocol

Most common protocol is Internet Protocol, responsible for taking the formatted segments from TCP, assigning the logical addressing and encapsulating theme into packets for routing to the destination host

Network Access Layer

Specific protocol depends on the type of media and transmission methods used in the physical network. Ex, ethernet

Transmission Control Protocol (TCP)

ensures reliable delivery, breaks up a message into small pieces called segments and passed to the IP process for packet assembly, the segments would be resent if lost. responsible for reassembling the message segments and passing them to the application, used by FTP and HTTP,

UDP

“best effort” delivery system, preferable with applications like streaming audio and voIP, retransmissions are undesireable, used by DNS to resolve a name.

Port

Numeric identifier within each segment that is used to keep track of specific conversations between a client and server, managed by the Internet Corporation for Assigned Names and Numbers, can be broken into three categories

Well-known ports

Destination ports that are associated with common network applications. range of 1 to 1023

Registered ports

Ports 1024-49151 can be used. Used by organizations to register specific applications such as IM applications

Private ports

Ports 49152-65535. often used as source ports and can be used by any application

Source port

Dynamically generated by the sending device to identify a conversation between two devices, common for a device to send multiple HTTP service requests to a web server at the same time, each conversation is traced based on the ports

Destination port

Client places a number in the segment to tell the destination server what service is being requests, a server can offer more than one service simultaneously

Socket

Combination of the source IP address, source port number, or the destination IP address, destination port number, used to identify the server and service being requested by the client enable processes

netstat

Used to list the protocols in use, the local address and port numbers, the foreign address and port numbers, and connection state. Can be used to verify connections