Glossary of Terms

 

CAN - Connection Authentication Negotiation. CAN refers the use of headers in HTTP messages by browsers and servers to negotiate the protocol that will be used to transmit authentication credentials. The most common protocol is NTLM.

 

CAN Transactions - The additional transactions required to negotiate the authentication protocol. Depending on the protocol and the state of the connection, there will usually be 0, 1 or 2 CAN transaction for a single transaction attempted by the Virtual User.

 

CAN Duration- The total duration of all CAN transactions that were required to complete a transaction. N/A if no CAN transactions were required.

 

NTLM - A protocol used by Microsoft Web Servers (if enabled) to accept authentication credentials from the browser.

 

Page Duration - The total time to complete all the transactions for a web page. This time starts when a connection for the first transaction is initiated and ends when the response for the final transaction is completed. The page duration does not include the think time after the page is completed.

 

Repeat delay - the delay between the time when a VU finishes a testcase and begins the next.

 

Sample - A set of data collected during a specific time period.

 

Sample period - the length of time during which a sample was measured.

 

SNI - Server Name Indication. This is an extension to the TLS protocol which the browser sends the hostname of the server it is attempting to reach to the destination server. This extension allows for Virtual Hosting of secured sites.

 

Testcase - A series of web (HTTP) transactions between a client and one or more servers. A testcase is usually created by recording the interactions between a browser and the servers. The testcase is represented as a series of pages; each page can contain one or more transactions.

 

Testcase Elapsed Time - the total time to perform all the pages in the test case and the intervening periods of think time. This will usually be much larger than the sum of all the Page Durations in the testcase, due to the addition of the think times.

 

Think Time - The time delay between the end of one page and the start of the next. The name reflects that this time delay represents the time the user spends reading, entering data or thinking about the last page received.

 

TLS - Transport Layer Security. The modern protocol for ensuring traffic between a client and server is secured. Used for HTTPS communications.

 

Transaction - A pair of HTTP messages (request and response) between a client (e.g. browse) and a server.

 

Virtual User - A simulation of a real user using a browser (or other web application) to interact with a server