Some of the standalone clients have pinned certificates. ms-office365-base (core functionality of O365 applications).Ms-lync-base (matches the core functionality of the application).In practical, configure the rules to be more specific by replacing any any rule to match the correct zones, Users, source and destination networks matching the network in addition to adding the app-ids.Īt a minimum, the following App-ID has to be whitelisted for Skype For Business to function properly. The rules configured below are in a LAB environment to demonstrate app-ids needed for skype application.

To Allow Skype in your network, the following App-IDs have to be whitelisted on your Palo Alto Networks firewall:Ĭreate security policies under Policies > Security as illustrated in the screenshot below to allow Skype to function. Despite the fact that it's a closed-source application based on proprietary protocols, T he proprietary and evasive behavior of Skype indeed poses a security challenge to enterprise networks, particularly given its ability to transfer files and information without visibility or control. The peer-to -peer network offers increased connectivity and scalability, and also provides firewall traversal and dynamic routing to evade corporate firewalls. Skype's underlying technology leverages a distributed peer-to-peer architecture to route multimedia packets among the users as opposed to centralized servers. Moreover, it supports integrated instant messaging (IM), chat, file transfer, video conferencing, and a global directory. Its major strengths include the ability to provide connectivity through firewalls and NAT (network address translation), support for a large number of active users, and privacy pro tection via the use of strong encryption. Skype compliments and competes directly with existing phone services, from traditional POTS to VoIP service s. Skype is best known as a peer-to-peer IP telephony application developed by Niklas Zennstrm and Janus Friis, also founders of the file sharing application Kazaa and the new peer-to-peer television application Joost.

Open skype application