Armstrong Power Steering WAN proposal

Robert Cr
aig

Chichester College


30/10/2013


Page
1




Armstrong Power Steering WAN proposal


1.

Introduction


The following report has been produced in order to describe WAN, web and internet
technologies, services and its uses.



2.

Information

This Information was collected from:

Class notes and various we
b
resources (referenced as appropriate)



2.1

WAN Technology




WAN
–

Wide Area Network(s) allows geographically distant
machines or networks to effectively communicate with each other
just like on a LAN,
however the speed of the interconnected
system, wil
l only be as
fast

as the
slowest

link, so if there was a
10mbps LAN and it was connected to a 100mbps LAN using WAN
technology, the speed of the data transmission would only be
10mbps between the two networks.


Several WAN technologies and services are lis
ted below:
-


Packet switching
–

ATM

(
Asynchronous Transfer Mode)

Circuit switching
–

ISDN

(
Integrated Services Digital Network)

PVC (
Permanent Virtual Circuit
)

SVC (
Switched Virtual Circuit
)


Asynchronous Transfer Mode (ATM)

“
A high speed, connection
-
orie
nted switching and multiplexing
technology for transmitting information across a wide area or local
area network in units called cells. ATM divides information up into
fixed
-
length cells capable of transmitting several different types of
traffic simultaneo
usly. It is asynchronous in that information
streams can be sent independently, without a common clock
”

An ATM circuit is a high speed multiplexing technology used for
transmitting information or data across a network.

Information
can be sent independently

without relation to a common time
synchronisation or clock.


ISDN

(Integrated
Services

Digital Network)

ISDN is a widely available digital communication route on existing
telephone copper wire with low noise and high digital quality.
Speed is about 64 to
128 Kbps. ISDN needs ISDN modem in both
ends of switches. It is charged by usage time and needs an
external power source to run the modem.



PVC

Robert Cr
aig

Chichester College


30/10/2013


Page
2



-

A permanent virtual circuit (PVC) is a software
-
defined
logical connection in a network such as a
frame relay

network. A
feature of frame relay that makes it

a highly flexible network
technology is that users (companies or clients of network
providers) can define logical connections and required
bandwidth

between end po
ints and let the frame relay network technology
worry about how the physical network is used to achieve the
defined connections and manage the traffic.

http://sea
rchnetworking.techtarget.com/sDefinition/0,,sid7_gci214
317,00.html


A PVC (Permanent Virtual Circuit) is a logical connection in a
network determined by software
over an
in
direct hardware
connection;

this allows multiple PVC’s to share the same physical
c
onnection, while effectively being on visibly separate connections.



SVC

A switched virtual circuit that is only active as long as data is being
transmitted; once communication is terminated the connection is
also terminated.



2.
2

WAN Services



VNC
–

V
irtual Network Connection

A VNC allows a machine in a geographically remote location to
connect to a local network, and have access to all the network
resources from that remote location. (Often used with teleworking
or a wireless connection.)

VNC allows f
or remote access to the main network without a direct
physical link into the network.


VPN
–

Virtual Private Network

A VPN allo
ws several users in different locations to create a Virtual
Local Area Network giving all the adv
antages of a Local Area
Network
(such as LAN gaming, application and resource sharing)


VoIP
–

Voice over Internet Protocol

A VoIP program allows people to talk to each other
over the
internet
as though over a regular phone call
.
(Requires computer
with network connection, microphone and

(head/ear)phones or
speakers
.

This is a cheaper and often more convenient method of
talking to someone than a regular phone call,
it also uses less
resources as a direct link between the sender and receiver does
not need to be established, therefore allo
wing the same physical
hardware to support more than 1 call at a time.

Video
-
Conference


An application that makes use of both
visual

and
audio

transmission over a network. This allows geographically remote
users to talk to each other ‘face to face’ over v
irtually any
distance.

This is very useful for conducting business meetings with
other employee’s or
businesses

in other countries.


Robert Cr
aig

Chichester College


30/10/2013


Page
3



While the above list is not exhaustible, it does list several of the
main/most commonly used applications of WANs.





2.2

WAN
Protocols

and the OSI


Main WAN protocols:


Protocol


Function

OSI Layer


TCP

Transmission Control
Protocol


4
-

Transport


IP

Internet Protocol


3
-

Network


FTP

File Transfer Protocol

File Transfer
Protocol. A TCP/IP
standard protocol
that allows a us
er
on one host to
access and transfer
files to and from
another host over a
network.

4
-

Transport


PPP

Point to Point Protocol

A data network
circuit with one
control and one
tributary.



Telnet


A user command
and TCP/IP
protocol used for
accessing rem
ote
PCs.



SNTP

Simple Network Time
Protocol




SMTP

Simple Mail Transfer
Protocol




HTTP

Hyper Text Transfer
Protocol




HTTPS

Hyper Text Transfer
Protocol Secure




LLC

Logical Link Control















Robert Cr
aig

Chichester College


30/10/2013


Page
4



Visual representation of the OSI Model show
ing various protocols used:

Upper Layers

Layers 7 through 4 comprise the
upper layers of the OSI protocol
stack. They are more geared to the
type of application than the lower
layers, which are designed to move
packets, no matter what they
contain, from o
ne place to another.


Application Layer 7

This layer defines the
communication language or
protocols that should be used for
communication, as well as the
communication material/content.


Presentation Layer 6

“
When data
is

transmitted between
different typ
es of computer
systems, the presentation layer
negotiates and manages the way
data are represented and encoded.
For example, it provides a common
denominator between ASCII and
EBCDIC machines as well as
between different floating point and
binary formats.
Sun's XDR and
OSI's ASN.1 are two protocols used
for this purpose. This layer is also
used for encryption and
decryption.
”


Session Layer 5

T
his layer determines the times at
which data transmission may
commence and ensures data is sent
in a specific order

ensuring that the
last packet was received before
sending the next one.

“
In practice, this layer is often not
used or services within this layer
are sometimes incorporated into the
transport layer.
”


Transport Laye
r

4

This layer is responsible for overall

end to end validity and integrity of the transmission. The lower layers may drop
Robert Cr
aig

Chichester College


30/10/2013


Page
5



packets, but the transport layer performs a sequence check on the data and ensures
that if a 12MB file is sent, the full 12MB is received.
”


"OSI transport services" include
layers 1
to

4,
these are
collectively responsible for
delivering a complete message or file from sending to receiving without error.

Lower Layers

Layers 3
to

1 are responsible for moving packets from the
sender

to the
receiver.


Network Layer 3

“
The networ
k layer establishes the route between the sender and receiver across
switching points, which are typically routers. The most ubiquitous example of this
layer is the IP protocol in TCP/IP IPX, SNA and AppleTalk are other examples of
routable protocols, whic
h means that they include a network address and a station
address in their addressing system. This layer is also the switching function of the
dial
-
up telephone system. If all stations are contained within a single network
segment, then the routing capabil
ity in this layer is not required.
”


Data

Link Layer 2

“
The data link is responsible for node to node validity and integrity of the
transmission. The transmitted bits are divided into frames; for example, an Ethernet,
Token Ring or FDDI frame in local area

networks (LANs). Frame relay and ATM are
also at Layer 2. Layers 1 and 2 are required for every type of communications.
”



Physical Layer 1

“
The
layer is the actual connection usually a copper wire or fibre
optic, which

links
one or more machines together
.
”


Taken and edited from http://www.pcmag.com



2.3

Internet and Web Technology


Web


Internet


HTTPS

Hyper Text Transfer Protocol
Secure

Telecommunication


HTTP

Hyper Text Transfer Protocol

FTP

File Transfer
Protocol

SHTML

Secure Hyper Text Mark
-
up
Langu
age

SMTP

Simple Mail
Transfer
Protocol

CSS

Cascading Style Sheet




HTTPS: Hyper Text Transfer Protocol Secure, this is a secure version of HTTP (Hyper
Text Transfer Protocol) which is commonly used
for
displaying web pages
in the
majority of web browser
s, for example any recognised or reliable sites will use
https:// instead of http:// to encrypt any personal information sent or received
during that session, e.g. Paypal, or any e
-
commerce website when accept personal
details or making payments.

SHTML: Se
cure Hyper Text Mark
-
up Language, this is a
n

encrypted html code
making it more secure and harder to inject extra code into.

Robert Cr
aig

Chichester College


30/10/2013


Page
6



CSS: Cascading Style Sheet, This is used to replace some of the older less recognised
html tags, and provide a much faster more fle
xible and useable method of formatting
a webpage.


FTP: File Transfer Protocol, This is a very old very simplistic method of transferring
files over a network between 2 or more machines, it operates on port 21, and is
largely considered very insecure.

SMTP
: Simple Mail Transfer Protocol, used for sending email messages from one
machine to another by ‘pushing’ information from the original machine, as opposed
to the standard ‘pull’

or request for information from the recipient machine.