Techniques for supporting subscriber sessions for access to an IP network include receiving from a first node at a different second node, a Dynamic Host Configuration Protocol (DHCP) formatted echo-request message. The echo-request message includes a DHCP option field that holds data that indicates an echo-request type. In response to receiving the echo-request message, the second node sends to the first node a DHCP formatted echo-reply message that corresponds to the echo-request message. The echo-reply message includes a DHCP option field that holds data that indicates an echo-reply type. When received by the first node, the echo-response message causes the first node to determine a connected state with the second node. Point to Point Protocol (PPP) keep-alive messages between a customer premises node and a remote access server gateway to an IP network may be replaced by these DHCP echo-request and echo-reply messages.