Microsoft supports the following networking features.

Ports, protocols, and IP addresses

Microsoft uses IPv4 and IPv6 addresses. Use of IPv6 addressing is optional and not required for connectivity with Office 365. Not all Microsoft 365 features are fully enabled using IPv6. For more information about Ipv6 support, see IPv6 support in Microsoft services.

Microsoft maintains a list of allowed IP addresses in the Microsoft help. For more information, see URLs and IP address ranges. For Office 365 operated by 21Vianet, see URLs and IP Addresses for Office 365 operated by 21Vianet. For Office 365 Germany, see Office 365 Germany endpoints.


We strongly recommend that you enable routing to the root domain names listed in the articles above (such as *, * and * instead of routing to specific IP address subnets. Relying on IP address subnets runs the risk of outages for your users as changes are made.

Bandwidth requirements

For information on bandwidth requirements, see Internet bandwidth planning.

Connecting to Microsoft

All Connections to Microsoft are done over the public internet or over a private Azure ExpressRoute connection, and are secured by SSL as appropriate. Azure ExpressRoute allows connecting directly to the global Microsoft network, bypassing the internet. A Microsoft networking partner provides the connectivity to the global Microsoft network.

For more information about Azure ExpressRoute, see Azure ExpressRoute for Office 365.

WAN accelerators

Microsoft does not provide support for customer-owned WAN acceleration and caching devices with Office 365. If you decide to use a WAN optimization controller to improve performance under conditions of high latency or low bandwidth, you'll need to disable it while troubleshooting service requests with Microsoft, and work with your device vendor for device support. For more information, see WAN Acceleration and caching devices with Office 365.

The global Microsoft network

The Microsoft networking infrastructure is comprised of a large global portfolio of data centers, servers, content distribution networks, edge computing nodes, and fiber optic networks to provide global distribution of services. Sophisticated service instrumentation and monitoring integrates at the deepest levels with each component, giving visibility into the data center, network backbone, internet exchanges and beyond, to help spot, diagnose and manage the cause of disruptions that arise. The network is built to maintain sufficient capacity even for large scale network interruptions without degradation of performance. For more information, see Microsoft Global Network.

To maintain the confidentiality and integrity of customer data, Microsoft keeps consumer services networks separate from Microsoft networks. Multiple techniques are used to control information flows, including but not limited to:

  • Physical separation. Network segments are physically separated by routers that are configured to prevent specific communication patterns.

  • Logical separation. Virtual LAN (VLAN) technology is used to further separate communications.

  • Firewalls. Firewalls and other network security enforcement points are used to limit data exchanges with systems that are exposed to the internet, and to isolate systems from back-end systems managed by Microsoft.

  • Protocol restrictions.

For more information, see the Office 365 Trust Center.

Feature availability

To view feature availability across plans, see Microsoft 365 and Office 365 platform service description.