大陸企業電子郵件業者

网易企业邮箱
http://qiye.163.com/mail/buy-price.htm

腾讯企业邮箱
http://tel.exmail.qq.com/portal/charges/introduce

ref:
企业邮箱

Set Up Attachment Filters - Google Apps Administrator Help

https://support.google.com/a/answer/97738?hl=en

Exchange Client Network Bandwidth Calculator

http://gallery.technet.microsoft.com/Exchange-Client-Network-8af1bf00

計算Client到Exchange Server所需頻寬