Is two-factor authentication required between two different segments of an internal network?
As defined in PCI DSS Requirement 8.3, two-factor authentication is required for all remote network access that originates from outside the entity’s own network, where that remote access could lead to access to the cardholder data environment. This typically applies where the access originates either from the Internet or from an ?untrusted” network or system; for example, access from a third party location or access by personnel from a portable computer over the Internet. Internal company communications between different network segments within the same entity is not generally considered remote access, as both locations are under the control of the same entity and would be considered ?trusted?. Two-factor authentication is therefore not required for communications between trusted segments of an internal network. However, if an internal network segment is used to facilitate access between an untrusted network and the CDE, two-factor authentication is required for connections from the untrusted network to the internal network.
If remote access is to an entity?s network that has appropriate segmentation, such that remote users cannot access or impact the cardholder data environment, two-factor authentication for remote access to that network would not be required. However, two-factor authentication is required for any remote access to networks with access to the cardholder data environment, and is recommended for all remote access to the entity?s networks.