This document will help to understand the basic idea of why DTP replaced IP in BI 7.0 for loading the data to data targets and data marts. This document highlights the main difference between DTP & IP and the significance of DTP over IP.
Author: Balamurugan A.J From SDN.

DTP and IP are tools used to load data from external system into BI. In BW3.5 and below versions, IP is
used to load data from source system to end data target. Whereas in BI 7.0, IP is used to load data only till PSA and DTP loads into data target and data mart. This document provides understanding of why DTP
replaced IP in BI 7.0.
First let us understand the basic concept about DTP and IP.

Data Transfer Process
Data transfer process (DTP) loads data within BI from one object to another object with respect to
transformations and filters. In short, DTP determines how data is transferred between two persistent objects.
It is used to load the data from PSA to data target (cube or ods or infoobject) thus, it replaced the data mart interface and the Info Package.
DTP fundamentals:

The InfoPackage is an entry point for SAP BI to request data from a source system. InfoPackages are tools for organizing data requests that are extracted from the source system and are loaded into the BW system.
In short, loading data into the BW is accomplished using InfoPackages.
IP Basics:

Reasons behind why DTP is Preferred over IP

DTP follows one to one mechanism i.e. there is one DTP per data target whereas, IP loads for all data
targets at once. DTP can load Full/Delta load for same target via same DTP which is not possible via same IP.

Delta Mechanism

DTP has separate Source to Target Delta handling mechanism. Thus, it helps in achieving,
•Possibility of having different data selection for one data source via different DTP (Same / Different
target) whereas this concept is not possible in IP.
•No DTP request exists in Reconstruct tab as it has separate delta handling mechanism for each
•No "Repair Full /Full Repair" concept in DTP as it has one to one delta mechanism.
•Deleting the data mart deletes the request itself not just status as in case of IP.

DTP filter's the data based on Semantic Key which is not possible in IP.
Having filters at IP, filters data before entering into BI i.e. PSA contains filtered data.
Whereas DTP-filter, filters data only at Data Target level thereby keeping all data at PSA.

Breakpoint can be set at data packet level at all the stages (Before Extraction, Before Data Transfer and
After Data Transfer.) whereas, breakpoint doesn’t exist in IP.

Error Handling
Temporary Data Storage and Error Stack improve error handling in DTP which doesn’t exist in IP.
(Temporary Storage area contains all the data whereas Error stack will have only erroneous records.
Temporary storage area can be switched On/Off at each stage of process)
•Error Handling for DSO is possible only in DTP.
•Reloading Bad Request without deleting request in the Data target is possible only in DTP using
Manual Update option.

DTP is faster as DTP data loading is optimized by Parallel process.
Data loading through DTP has no TRFC/LUWs generated at run time thus minimizing the loading time.

It's possible to migrate from IP flow to DTP flow if you are in BI 7.0 or above.
Create a DTP and set the Processing mode Serial Extraction, Immediate parallel processing to switch from IP to DTP without data loss.
Migrating IP flows to DTP
•Note 920644 - Date store with emulated Data Source: InfoPackages/DTP

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