6.3.2 SLA Defined for Case Study 

For the definition of the SLA, if was first necessary to examine how Yahoo Mail actually 

implements the delivery of the service using HTTP. The typical features that are offered in 

the service needed to be assigned to service functions. The service functions created for the 

case study were as follows: 

6.3.2.1  

Service Function 

URL  

Method 

Login to Mail 

http://login.yahoo.com/config/login? 

POST 

Read Mail 

http://us.f1.mail.yahoo.com/ym/ShowLetter? 

GET 

Compose Mail 

http://us.f1.mail.yahoo.com/ym/Compose? 

GET 

Delete Mail 

http://us.f1.mail.yahoo.com/ym/ShowFolder? 

POST 

Send Mail 

http://us.f1.mail.yahoo.com/ym/Compose? 

POST 

Search Mail Form 

http://us.f1.mail.yahoo.com/ym/Search? 

GET 

Search Mail Results  http://us.f1.mail.yahoo.com/ym/Search? 

POST 

Logout of Mail 

http://us.f1.mail.yahoo.com/ym/Logout? 

GET 

Attach to Mail 

http://us.f1.mail.yahoo.com/ym/Attachments? 

GET 

Table 9: Yahoo Mail Service Mappings 

It is worth noting that the same URL and method can provide the different service functions. 

The implication of this will be discussed later.  

For the next step, parameters were assigned to each service mapping. For the purpose of the 

case study, three derived performance parameters were created to monitor which consisted 

of the following.  

HEADER RESPONSE TIME 

Response time in milliseconds to receive a reply header 

from time that request is sent 

ENTITY DOWNLOAD RATE  Transfer rate in Kbps of reply body from service  

ENTITY UPLOAD RATE 

Transfer rate in Kbps of request body to service 

Table 10: Table of Derived Parameters for Case Study 

a

a