[CentOS] network intermitent, not sure if virtualization issue

I have a computer I am using to host a virtual machine.
Centos 6, for both, 64 bit.

The host machine's network connection seems fine. No problems.
Trying to access the virtual machine is usually fine.

but then, poof, ssh, http, ftp, all lose connection for about a minute. 
Then they come back up.

I looked in all the logs on both machines, could find nothing, but not 
sure where to look.

My question, would this be a setting on the VM as a webserver, some new 
centos 6 setting that just
times out network when not in use? Or something that I did when I bonded 
my eth ports and bridged them?

The bond covers the two onboard eth ports and one port from an add on 
network card.

It is intermittent, seems to happen whenever, but service network 
restart on the webserver
seems to fix it immediately, but it also just fixes itself too.

is there some setting with centos 6 that must be changed to allow 
constant 'uptime' of the network?