Re: [vnrg] Logical vs. virtual

[Sunay Tripathi <sunay.tripathi at gmail.com>]

On 07/15/10 09:51 AM, Joe Touch wrote:
<SNIP>
>
> A physical network can't be relocated while running. A virtual one
> can. A physical network doesn't ensure separation from other physical
> networks; a virtual one should, IMO.
>

Joe makes the critical point. The virtual network can be cloned,
snapshotted and migrated as a whole (something that I am working on
right now) but the virtual network lacks the separation of a physical
network which is very important feature to have.

Take the simple example: If I have a bunch of hosts connected via a
dedicated 24 port 100Mbps switch and 23 machines are trying to bang
on the 24th machine, then I only hurt myself or the packet drop is 
related to just my traffic. Now on the other hand if I apply
pn2vn (physical network 2 virtual network) to my network and move
to a 10Gbps physical switch and apply the same workload,
I am going to impact someone else (sharing the 10Gbps network with
me) and possibly not see any packet loss.

Now implementing this across one switch might be a vendor implementation
but I think making this work across a collection of switches and hosts
might benefit from a standard.

Cheers,
Sunay