which protocol to use

Which protocol to use?

Written by TnT Admin

Monday, 21 April 2008 00:00

Typically for newbies, the question after getting their first copy of LoadRunner and installation of Vugen will be, “Which protocol to use?”. They post online or to the support to ask, “I’ve got a Java/.NET applicaton, and there are many protocols from the list of Vugen. Which Protocol should I choose ” or “…can you advise on the protocol to use?”.

The fact is that it doesn’t really matter the type of language that was used to developed the application, but rather the type of communication method or protocol that the application is talking to the server. Previously, in "What's LoadRunner?", we mentioned that the tool captures network traffic while recording which is the core understanding that we must align when using this tool.

For example, an application can be developed using .NET 2.0 framework, is window-based (Win32). This application can be part of a N-Tier architecture that utilizes HTTP or HTTPS to communicate to the middle-tiers or a 2-Tier architecture that talks to the database directly using ODBC, ADO or JDBC-ODBC.

Similarly, an application can be developed using Java, but it talks to the middle-tier using RMI-Java or HTTP, or to its database using JDBC.

Despite the language or the type of of Applications (Java or Win32, etc.), the Load Tester must understand the communication method in order to determine the protocol to be used. This is done by consulting the development team of the application (which usually the Load Tester do not have such knowledge).

To understand the protocol used by the application (client to server), you can do the following.

1. The easiest way, check with the application team or vendor, particularly the software architects and the developers. They should be able to provide such information. If they don’t, it ’s time to doubt the experiences of the application team.

2. Use WireShark Network Analyzer to sniff the traffic communication when the application is running. More details of the usage can be found in the provider’s site. You should be able to see the protocols under the protocol column after you start capturing the traffic.

3. Use netstat -a to determine the protocol and port number. For example, the protocol is TCP and port number is 80, it could signifies HTTP. The caveat for this is that netstat -a only display protocol in IP, IPv6, ICMP, ICMPv6, TCP, TCPv6, UDP, or UDPv6 (/? help for more information), which means you may need to guess the protocol according to the protocol (TCP) and port number.

4. Use Winsock protocol to determine the protocol via the data files. Winsock captures all traffic of any type at the socket level and writes it to the data file. From the data file, you will then find signatures of the protocol such as HTTP requests and responses in the context of HTTP.

Hopefully this methods are sufficient for you to determine the protocol used. Feel free to comment if you have a better method.

Last Updated ( Tuesday, 16 September 2008 10:54 )

Comments (11)

I presume that it will still be going through the SAPGUI front-end right? In this case, SAPGUI vuser should be used.

Has anyone used Loadrunner to record SAP BEX Analyzer script? If yes, please share your knowledge.

You may want to read up on this document, Does LoadRunner 7.x support JDBC? from the Support site. From my understanding till date, JDBC is not supported and this require you to generate the script manually.

What protocol need to be selected for Java pplication and It is using JDBC for talking to the data base?

Javascripts are recorded as plain text (HTML) to Vugen. What I think is causing the problem is some expired session data being re-send back to the server. This you have to verify and perform correlation if necessary. :)

Hi, When I add members to the group & send invitation to join the group by clicking on link 'Send invitation', one java script runs for validations on check boxes(Which users selected out of the list, what is the invitation status? etc) & alert pop-up gets displayed: "Members invited successfully." While recording it works fine, but when playing it back, it fails on the link 'Send invitation.

Yes, it can be done. You may want to look up the Virtual User Generator Guide to find out more about the application and database that you are working in the 2-tier client-server architecture. You can see that there are alot of protocols that you can select from as well from Vugen. :)

Hi, I used the loadrunner successfully for web application. Now I wonder if LR can be used for client server archtechture too. The application is desktop application with remote database on the same network or it may also be on wan. Please let me know, waiting eagerly for your response. Thanks, Deepak Gupta

Hi Shital,

Javascripts are not recorded. There is no functional aspect that is being recorded. Javascript will be recorded as pure text in the HTML page. Vugen will not render the javascript but treats it as text. Can you provide more details of the problem? Can't really make out on the "When I try to play back my test, it fails to the link & my members can not be invited."

We are using HTTP protocol for communication between client & server.

I am working on a social networking site. When I am creating group & trying to sent invitation to the members, some java script pop-ups are running. When I try to play back my test, it fails to the link & my members can not be invited. Can you please help me?