SausageFingers's questions

I have a production server that is responsible for controlling a factory. The server runs a number of control applications and a SQL server.

The problem I have is that one of the applications that communicates with a PLC is reporting communication problems at seemingly random intervals.

Using resource monitor, I have noticed the network activity drops sharply whenever this problem occurs. My VNC connection is not interrupted and the server responds to pings from other computers during the event/blip, however, other computers on the network which run applications connected to the SQL server are freezing till the network traffic restores.

Screenshot of the resource monitor network graphs at the time of a blip. the first arrow is when we start experiencing communication problems and the second arrow is when things return to normal:

I have analysed the SQL server at these times and there are no resource waits and the number of batches processed per second are also low. I also did a trace on the SQL server at the time of a blip but this did not reveal anything significant.

At the moment just before the network activity drops there are no other indications this is going to happen. The CPU is low and memory is usage remains at about 70%.

Could this be being caused by external factors affecting the network or maybe something wrong with the network card?

Edit (additional information):

This is a performance monitor for packets sent and received at the time of the blip:

I have a hyper-v server and several VM's (Virtual Machines). All the VM's are connected to an external network.

I have tried to share a folder on the host and connect via the VM, I can do this but I'm prompted for a user name and password (as you would expect). I do not want to enable the "Everyone" group permissions as the physical host server is on a network of other servers.

I have created a new virtual internal network in Hyper-V and given it's adapter a static ip of 33.0.0.100. I have added the virtual adapter to one of the VM's and set to IP to 33.0.0.2 (as advised here). Again this seems to work but I'm still prompted for a user name and password.

Am I on the right lines here? I just want to share a directory from the host to the vm's without exposing the share to other servers on the network.

I support a local organisation which works with school children. The organisation has 15 Vista and Windows 7 desktops, all joined to the same workgroup. All the computers simply connect to a wireless router.

Up until now all the computers ran a single limited account. We use Windows Family Safety to protect the users on the internet and we manually restrict particular social networking sites and various other sites.

We now have a need for users to be able to log into the computers with their own accounts. If we continued to use Windows Family Safety we would need to join each account up to the service, something we would like to avoid as this would be difficult to manage.

Are there any solutions that we can operate centrally that automatically block out known bad sites and also allow us to blacklist sites. Ideally the rules we set should be for each computer, regardless of the account.

Would love to hear your thoughts and ideas? Maybe I'm going about this all wrong and there is a better solution in the form of external hardware. Please advise.