Does your company allow Skype in network? What are reasons to forbid it, and how it is enforced? Is it done for security concerns?
Skype is P2P so it eats up bandwidth. Also nominates users with good connection to serve as hubs, forwarding connection between other users. That eats up lot more bandwidth and CPU. You have absolutely no control over it. Other problem with Skype, that being P2P it uses firewall punch-trough, which of course admins don't like.
Yes we do.
For small offices it is a great tool for communicating. It can use lots of bandwidth but if the company does lots of traveling, the cost savings from international long distance can be great.
We actually use it more for chat than voice, but since it does both we don't need another IM client on the desktop.
We allow and use it, although less than we used to. It used to be our main solution for inter-office communication internationally, but we now have a wider VoIP network that takes its place. We still use it to communicate between folks working at home and folks in the office on occasion, but even that's falling away as Office Communicator takes its place.
That said, we've seen no reason to block it (or external IM, for that matter)
We do not allow Skype behind the firewall. We provide a good phone system, with lots of good features and excellent rates. The primary reason is to control network performance, secondary reasons are to control what gets through the firewall and to reduce opportunities for non-work activities.
We do allow the "road warriors" to have it on their laptops, but don't support it. Several of them use it to communicate with the home front.