address translation and their types,nat,pat,sat,dat

3. CONTENTS
 DEFINITION
 PROCESS
 TYPES
 ADVANTAGE
 DISADVANTAGE

4. DEFINITION

5. PROCESS OF ADDRESS
TRANSLATION
 The address translation process can be
described as follows ---
1-Break the logical address down into page
number and offset.
2-Use the page number as an index into a
page table to find the corresponding page
frame.
3-Using the frame number found there
generate a physical address by
concatenating the frame number and offset
from the original address.

6. Translation tables are implemented in HW,
controlled by SW.
Translation table
Virtual Physical
addresses addresses
Data reads or writes
(untranslated)

7. Types of address translation
 Address translation comes in a variety of
types which are given below-
1- NAT (network address translation)
2-PAT (Port address translation)
3- Dynamic address translation
4- Static address translation

8. NETWORK ADDRESS TRANSLATION
. Network Address Translation (NAT) is a method of connecting
multiple computers to the Internet (or any other IP network)
using one IP address. This allows home users and small
businesses to connect their network to the Internet cheaply
and efficiently.

9. Static Address Translations
Static address translation establishes a one-to-
one mapping between a local and global address
or local and global address/port pair. When
specifying a static address translation or
address/port pair translation, you issue
commands to indicate how the translation is
applied, along with more specific variables that
further define the type of translation

10. DYNAMIC ADDRESS
TRANSLATION
Dynamic address translation, or DAT is the
process of translating a virtual address
during a storage reference into the
corresponding real address.

11. PORT ADDRESS TRANSLATION
With Port Address Translation (PAT), also known as
“overload” and [[Network Address Port Translation (NAPT),
the customer may map several internal addresses to one
public address. When using PAT, traffic attempts to engage
the original source port. If the source port is fully utilized,
PAT causes the traffic to find the first available port.

12. ADVANTAGE OF ADDRESS
TRANSLATION -
The advantage of address translation include-
1.Conservation of public addresses.
2.Protection of resources with private addresses
from external devices.
3.No need for readdressing of devices when
switching from one ISP to another.

13. DISADVANTAGES OF ADDESS
TRASLATION
1.Each connection has an added delay.
2.Troubleshooting is more difficult.
3.Not all applications work with address translation.