Dear all,     For the last months we are struggling to ensure QoS in S4B, we have been able to improve by adding all the URL, IPs and Ports that MS recommends for S4B:   https://docs.microsoft.com/es-es/office365/enterprise/urls-and-ip-address-ranges?redirectSourcePath=%252fen-us%252farticle%252fOffice-365-URLs-and-IP-address-ranges-8548a211-3fe7-47cb-abb1-355ea5aa88a2#skype-for-business-online-and-microsoft-teams   However we are still having problems. Since we are only using IPv4, do we need to also add the IPv6 ips  of that link?   I would appreciate it if someone with the knowledge could verify if the rules that we are using (attached) are the good ones for MX65.       Thank you very much in advance. ... View more