XML Data Compression - PowerPoint PPT Presentation

1 / 33

About This Presentation

Title:

XML Data Compression

Description:

Number of Views:75

Avg rating:3.0/5.0

Slides: 34

Provided by: MAlag

Category:

Tags: xml | compression | data

Transcript and Presenter's Notes

Title: XML Data Compression

1
XML Data Compression

2
Definition of data object used here

It is data wrapped in the form of object and has
valued attributes only, for example
Data Class
Data Object
Hotel
NewYork_beach_Hotel
String Location
Location NewYork
int Number_of_rooms
Number_of_rooms 125
int Number_of_employee
Number_of_employee 35

3
What is S-S data transfer ?

The process of exchanging huge amounts of data
between servers is called S-S data transfer ( a
definition used here)

Server A
Server B
Network
Server C
4
Example of S-S data transfer

Consider for example a California Tourist Agency
called BayTravelAgency would like to have
strategic partnership alliances with several
hotels in New York
In this regard they would like to get information
about all the hotels in New York form
NewYorkYellowsPages.com to do a survey
BayTravelAcengy will request the
NewYorkYellowsPages.com to send the information
about all the hotels in New York for their
research

5
Application
Request
CA Server
NY Server
CA db
NY db
Response
Hotel A
BayTravelAgency
NewYorkYellowPages.com
6
Why XML should be used here?

8
Problems with XML?

The data exchanged between BayTarvelAgency and
NewYorkYellopages.com will be huge ( for 1000
Simple hotel objects discussed earlier it takes
0.127MB). In reality it might take about 1MB
It takes a significant amount of time while
transmitting, especially when there are many such
request like

9
Server8
Server9
Server7
Server6
Server1
Network
Server5
Server2
Server3
Server4
10
How to overcome this, use compression but .?

Some compression algorithms may use a lot of cpu
cycles hence it will reduce the server
performance
If compression is used then all processors in
the network should understand it.

11
First problem can be solved using simple delta
compression

Location attribute with the same value New York
repeats in all the data objects
Sending it more than once is redundant .. How
to get rid of such similar attribute values?
Mention it once only ..if there is a difference
then send the difference alone for example

14
When using a delta compression ...

Order of the objects are very important to get a
maximum compression, for example (next 2
slides)
To find out an order which might produce a high
compression one can use the following steps
Create an attribute compression factor (ACF)
table

New York
ABC
Long Island
19

New York
ABC
Long Island
20

This simple method does not guarantee the best
data object order however it provides a good
order in a quicker time , with less CPU cycles

21
Difference between the real one and the
compressed one

22
The Challenge ...

Other xml parsers will see it as normal XML
document hence these may lead to
misunderstandings therefore ..
we suggest a new tag to be added to the XML
specification in order to achieve this new
document

CP-XML
24
What is CP-XML?