In last days IBM support was mailing about update of ip address range in IBM Connections Cloud servers. If you have implemented rules on you corporate firewall to allow IBM Connections cloud connections an update is required.
In this days some people is in holiday and i think this post could be useful to not lose this important news.
For NA datacenter the update is required ASAP because could impact on free / busy look up , in EU the add is less urgent because is the range of the disaster recovery site but you have not to forget it.
IBM Connections Cloud EU
IBM Connections Cloud NA
126.96.36.199/27 (188.8.131.52 to 184.108.40.206)
220.127.116.11/28 (18.104.22.168 to 22.214.171.124)
There is also the AKAMAI accelerator ip range but probably this is not changed between last table.
For tcp ip rule check you can the wiki page and in case of any trouble please remember you can contact the IBM Support via mail or phone.