Dear GLUErs,
attached to this mail you will find the latest version of the draft for GLUE 2.1, with the inclusion of the Cloud entities. Respect to the last draft sent, I have performed the following changes (all changes/additions are highlighted in yellow in the document):
- I reviewed the representation of the virtual resources available to the VM, and decided to adopt the OpenStack model+GPU, so RAM,CPU,GPU,Network (public or private),OS Disk and Ephemeral disk. This model is the more general I could find between the open source middlewares and should fit almost all of them.
- I reviewed the representation of service pricing (costs). The overall pricing issue is quite complex, and a comprehensive standardization of pricing schemes is way out of our scope. Anyway, for brokers and markeplaces to consume this information and select the "best" site for the user, I have included a simple representation via price entities which are associated to the VM image disk and resource. The final price for the VM is calculated as the sum of all the associated price elements (eg. RAM, CPU, OS License, etc...).
- I added SLA (service level agreements) related to the cloud service. This is important for brokers (eg. you may select the site with lower price, but only if it provides the SLA you need). I did not standardize SLA representation, but just added a string to represent the SLA, which can be an URL or a short nametag (eg. 99% Avaliability, best effort, etc...).
- I added a service ToC parameter as an URL reference to the ToC per the site. When you program a cloud broker, you need your user to accept the ToC of each of the cloud providers at first use. I think GLUE is a nice way for the broker to access the ToC of all the different sites in an uniform way.
- I added the possibility to specify pre-set access credentials for the VM images. This information is relevant to the broker system if cloud-init is not supported by the provider or the image.
Cheers,
Salvatore.