So "Hello" out there ...
my daily reflection:
I try a little adult to act as the first post! :)
Anyway today we went to, among other things: The repetition of yesterday ... :) We then cut again the following topics:
Peer-to-peer model and client-server model is queried in the test!!
peer-to-peer network - all members are equal, and offer something (can) take some.
client-server model - A server provides the Client a service provided, eg DHCP, DNS, Terminal Server (Remote Desktop, RDP), Web server, mail server, Telnet server, SSH server, database server
! Should network devices and network components may be differences in the test! !
devices
PC (Unix, Linux, Windows, MacOSX, server, IP phones,
network printers, network storage, ...
place ... the users applications.
network devices
Hub , Switch, Bridge, Access Point,
routers, firewalls, modems, ...
are ... for the transfer of messages between the
Devices responsible.
Media
copper or fiber optic cables, serial
cable, wireless transmission (WLAN ),...
physically connect the devices ...
for data transmission from one device to another
.
Rules Rules, Agreements, standards, protocols
. eg ISO / OSI, Ethernet,
HTTP, HTML, etc. ..
.. comply with rules
agreements or standards for the exchange of messages. For example, the agreement on the "same language" in the network in spite of different operating systems.
Messages
www, mail, pictures, music, video, voice
...
... Are various data, information, files, signals that are transmitted on the network.
There was also a perceived decade switches to ... ;-)
A switch (English switch, and switch) is a coupling element that connects network segments. The term refers generally to a further development of a network bridge - the processes and transmits data on the Data Link Layer (Layer 2) of the OSI model - an active network device. Switches to process additional data on the network layer (Layer 3 and higher) are often referred to as Layer 3 switches or Multilayer switches. The first Ethernet switch was Kalpana introduced in 1990. In addition to Ethernet switches is also available Fibre Channel (FC) switches, a non-FC routing capability standard protocol defined in the field of storage networks, designed as the successor to SCSI for high-speed transmission of large amounts of data. The appropriate device at Layer 1 level is called the Hub. Switches work with MAC addresses.
additional switches:
ARP query = MAC-address query (if only IP address is known - for shipping switch / router, gateway)
by encapsulation protocols is possible.
^---------- If this movement is a read-learning IT, PLS COMMENT - THE VOTE ? !
network types, spatial / geographical distinction
(Exam !!!):
PAN [personal area network]:
PAN is a special peer-to-peer connection between two devices. eg mobile phone and PC (Bluetooth)
LAN [Local Area Network]:
Local network. Basically as a neighborhood.
MAN [Metropolitan Area Network]:
two or more connected sites. eg within a city.
WAN [Wide Area Network]:
Two connecting cities.
GAN [Global Area Network]:
Worldwide network. as the Internet.
topologies
----------
The topology point-to-point (point to point):
The point-to-point topology is a connection from one terminal to another . This
usually are dial-up connections in the WAN, for example in a corporate network or the Internet.
point-to-point connections are usually implemented in Germany using an analog modem or ISDN card.
ring topology (Token Ring)
The ring topology is an outdated bus topology, which is physically or logically arranged annularly
. As an example, consider networking technology Token Ring "here is a token (like a talking stick) in the district passed.
The computer, the first reached a "free" labeled token is allowed, a data packet to be hanging
the token and the token as "occupied" mark. This "busy" token is circulated from one computer to another passed until it reached the receiver.
The receiver "takes" the data packet intended for him, marks the token as a free
and passes it in a circle. Thus, to avoid collisions between data packets.
bus topology
The bus topology may be physically or be arranged logically.
- A physical bus, eg for 10Base2 and 10Base5 Ethernet to be found. This coaxial cable, T-pieces for random access and resistance were used with 50 Ohm.
- A logical bus is used in hubs. Here, the cables are connected star-shaped
, logically the net but still works like a bus.
- Mapping of physical bus with 10 Mbit / s over coaxial cables with Endwiederstanden
star topology
case of networks in star topology, all the participants to a central unit connected
the "Data Junction" for all participating units represents. The systematic presentation in a network plan would form a star show.
- We distinguish between the physical star topology and logical
star topology.
- At a stroke we have a physical star and logical bus. Therefore
can always happen, only one data packet at a time the hub.
- In a switch, we have a physical and a logical star, there are also possible via a switch
multiple connections.
When multiple computers are connected to a Übertragunssystem, so this is called a BUS (Latin: Bus = all together)!
topologies can be queried!
Hubs
# # # #
The Hub (hub in, hub '[technically], node') refers to telecommunication devices that connect network nodes (physical) star-shaped. Normally, the term hub for multi-port repeater is needed. They are used to network nodes or other hubs, such as through an Ethernet, to connect with each other. We speak with hubs from a collision domain.
CSMA / CD
end Ethernet data transmission using CSMA / CD:
first Before a station transmits data, it hears from the line, whether it is free.
second With free line is sent, otherwise we waited.
3. Send by chance two stations at the same time a collision occurs, the frames are to
subkey collision fragments (\u0026lt;64 bytes).
4th While the show is still off line hort.
The reception of collision fragments, a collision took place is discovered.
5th Thereafter, a jam signal (32-bit sequence of 010,101th.) Sent, whereupon all
stations broadcasting also want to wait a random period of time before they try a
new connection.
6th All stations in the network tests the process received data packets and only the
packages, for they are intended. Packets for other stations are not passed to the upper layers and discarded.
data transmission devices (Will be confirmed)
---------------------------
(send and receive)
Simplex Only one direction.
half duplex: alternately in both directions, however.
full duplex: In full duplex will each send a pair to use and one for reception. (CSMA / CD is no longer needed and shut down).
This was listed in today's rough main themes, especially for me again! ;-) Well then
ma mere net eggs start to rock! :)
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