[occi-wg] Opinion Poll: IaaS or PaaS ?

[André Brinkmann]

Hello Randy,

thank you for the explanations. Nevertheless, there are still some  
open issues (at least from my side);

Am 30.06.2009 um 19:59 schrieb Randy Bias:

>
> On Jun 14, 2009, at 11:10 AM, André Brinkmann wrote:
>> sorry for interfering with your discussion, but I am only reading  
>> your Email list since a week. From my perspective, IaaS (and OCCI)  
>> only deals with an execution platform for (a collection of) virtual  
>> images. The operating system itself and the "virtual" hardware  
>> (Virtual MAC, ...) is part of the virtual image and therefore does  
>> not belong to an IaaS environment.
>
> Actually, I think this is provably untrue.  The virtual hardware  
> will almost certainly belong to the infrastructure and not the VM  
> itself.  For example, right now GoGrid provides 3 NICs, but Amazon  
> provides 1.  Both are Xen-based platforms.  Other systems provide  
> arbitrary numbers of NICs.  Since the virtual hardware is supplied  
> by the underlying hypervisor layer and it's configuration the  
> virtual hardware is part of the IaaS platform.
>

Your point is (in this case unfortunately) correct. I think that this  
is a drawback of current IaaS providers. In principle, the restriction  
to a limited number of NICs leads to vendor lock-in, e.g. it might  
become difficult to port applications from GoGrid back to Amazon.

> In addition, most of the hypervisors request you to use Ethernet  
> MACs that have Vendor IDs relevant to the hypervisor under which  
> they are used.  For example, VMware uses 00:0c:29 for dynamically  
> assigned MACs.  This leaves only 16M possible Ethernet MACs across  
> all VMware installations.  The risk of collision when moving a  
> VMware VM from one cloud to another is very high.  Because of this  
> vendors will almost certainly provide (and hardcode for security  
> reasons) the MAC addresses for servers.
>
> In other words, the virtual hardware and the virtual MAC are tied to  
> the IaaS platform and not the VM.
>

Correct and it also makes sense, as the MAC address in a conventional  
system is also part of a physical machine and therefor part of the  
infrastructure.

> One can certainly argue whether the OS is the bottom layer of PaaS  
> or the top layer of IaaS, but there is absolutely no doubt that it's  
> the primary interface between the two.
>
> I would argue that the traditional notion of OS as a platform comes  
> from the idea that the OS provides a set of runtimes (libraries,  
> resources, and facilities) upon which you can 'load-your-code-and-go'.
>
> So, if platforms are 'load-your-code-and-go' systems, then an OS  
> itself is not a platform.  By default not every OS is ready to have  
> code loaded and ready to go after a fresh install.  Most require  
> some significant configuration.
>
> So if we want to split hairs, an 'OS' is probably the top layer of  
> an IaaS platform and a 'configured OS' is probably the bottom layer  
> of a PaaS.
>

I do not want to split hairs, but I am interested (from a customer  
perspective) to be able to deploy arbitrary OS-images inside my  
virtual machine, so the OS is not part of the service offered by the  
Iaas-provider.

> BUT, if we dig deeper and look at runtimes that don't sit on a  
> specific OS (JVM, Mono, CLR, etc.) then one has to assume that while  
> the run times are typically attached to an OS, they don't have to be.
>
>> Nevertheless, services like VPNs, DNS, and DHCP are services, which  
>> are typically provided by the infrastructure outside of the virtual  
>> machines and I would be happy if you would include a description of  
>> these services inside OCCI.
>
>
> I wrote this up fairly extensively here:
>
> Defining Infrastructure Clouds | Cloudscaling
>

Thank you for your comments

André

>
> Thanks,
>
>
> --Randy
>
>
> Randy Bias, Cloud Strategist
> +1 (415) 939-8507 [m], randyb at neotactics.com
> BLOG: http://cloudscaling.com
>