Required firewall rules for the Network Device Enrollment Service (NDES)

Implementing a Network Device Enrollment Service (NDES) often requires planning the firewall rules to be created on the network. The following is a list of the required firewall rules and any pitfalls.

The Network Device Enrollment Service (NDES) provides a way for devices that do not have an identifier in Active Directory (for example, network devices such as routers, switches, printers, thin clients, or smartphones and tablets) to request certificates from a certification authority. For a more detailed description, see the article "Network Device Enrollment Service (NDES) Basics„.

Clients to NDES

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NDES is a web-based service that can be used via HTTP and HTTPS. Accordingly, TCP ports 80 and 443 must be opened. However, the NDES administration web page should only be accessible via HTTPS.

Network protocol	Destination port	Protocol
TCP	80	Hypertext Transfer Protocol (HTTP, not recommended)
TCP	443	Hypertext Transfer Protocol Secure (HTTPS)

NDES to the Certification Authority

Quite analogous to all other clients are the certificate request ports to the certification authority to open.

Network protocol	Destination port	Protocol
TCP	135	RPC Endpoint Mapper
TCP	49152-65535	RPC dynamic ports

NDES to the domain

The NDES server is usually a domain member, so the general rules for domain communication apply here.

Network protocol	Destination port	Protocol
TCP and UDP	53	Domain Name System
TCP	88	Kerberos
UDP	123	NTP
TCP	135	RPC Endpoint Mapper
TCP and UDP	389	LDAP
TCP	445	Server Message Block RPC Named Pipes
TCP	636	LDAP over SSL
TCP	3268	LDAP-GC
TCP	3269	LDAP-GC over SSL
TCP	49152-65535	RPC dynamic ports

Restore the default Windows Firewall rules

Enable-NetFirewallRule -Name "IIS-WebServerRole-HTTP-In-TCP"
Enable-NetFirewallRule -Name "IIS-WebServerRole-HTTPS-In-TCP"

Special case of role installation of NDES

During the installation of the NDES role, it is required that communication via RPC named pipes (TCP port 445) to the root domain controllers of the forest is possible.

See article "Role configuration for Network Device Enrollment Service (NDES) fails with error message "Insufficient access rights to perform this operation. 0x80072098 (WIN32: 8344 ERROR_DS_INSUFF_ACCESS_RIGHTS)"." for more information.