Firewalls. NetRelay accepts any type of Internet connection regardless of its origin, so it does not function in the place of a network firewall. Network firewalls are usually configured to only allow certain types of Internet connections originating from certain Internet addresses. However, NetRelay encrypts and decrypts all data passing through it, while network firewalls typically do not support encryption. Future versions of NetRelay will only accept connections from predetermined network addresses.

Virtual private networks (VPN). NetRelay only supports passing data between two predetermined computers, while a VPN supports encrypted data communication between any computers on two predetermined networks. However, a VPN usually requires the purchase and configuration of specialized Internet routers for both of the networks involved. Installation of these routers requires special networking expertise.

Software protocols. Software-only encryption methods such as Secure Sockets Layer (SSL) and Microsoft Point-to-Point Tunneling Protocol avoid the need for special hardware in supporting VPNs. However, both require the installation of special servers or are tied to a specific operating system.