How to use ionic behind corporate proxy

Hi,
I have install ionic in my system using npm install -g ionic , cordova was already installed.
But when I’m going to create any project using ionic start myProject, it is showing error.

The error is:

[INFO] Fetching app base
(https://github.com/ionic-team/ionic2-app-base/archive/master.tar.gz <https://github.com/ionic-team/ionic2-app-base/archive/master.tar.gz> )x Downloading - failed!
Error: connect ETIMEDOUT 192.30.253.112:443

I think this is due to corporate proxy.

How to resolve this issue ? please guide me.

Thanks
Saibal

Ask for the people that work on the infrastructure of your company to free the ports of the firewall to you download the repositories that an ionic project need.