Lantronix SLC 8000 Advanced Console Manager User Guide - Page 257

9: Device Ports Dial-back & Dial-on-demand A modem is configured to be in two modes: answering incoming calls to initiate a dial-back, and automatically dialing out to establish a PPP connection when IP traffic destined for a remote network needs to be sent. When either event occurs (an incoming call or IP traffic destined for the remote network), the other mode will be disabled.  For Dial-back, the user will be authenticated via PAP or CHAP (determined by the Authentication setting for the modem). For PAP, the Local/Remote User list will be used to authenticate the login and password sent by the PPP peer, and the site list will be searched for a site that (a) the Login/CHAP Host matches the name that was authenticated, (b) Authentication is set to PAP, and (c) the Port is set to None or matches the port the modem is on. For CHAP, the site list will be searched for a site that (a) the Login/CHAP Host and CHAP Secret match the name and secret sent in the CHAP Challenge response by the PPP peer, (b) Authentication is set to CHAP, and (c) the Port is set to None or matches the port the modem is on. If the remote peer requests PAP or CHAP authentication from the SLC unit, the Remote/Dial-out Login and Remote/Dial-out Password configured for the modem (not the site) will be provided as authentication tokens. If a matching site is found, its Dial-back Number, Allow Dial-back, Dial-back Delay, Dialout Login, Dial-out Password, Negotiate IP Address, NAT, and Modem Timeout parameters will be used for the rest of the dial-back connection instead of the parameters configured for the modem. Once the remote server is authenticated, if Allow Dial-back is enabled for the site and a Dial-back Number is defined, the SLC 8000 advanced console manager will hang up and wait Dial-back Delay seconds before initiating the dial-back. The SLC unit will dial, and if the remote peer requests PAP or CHAP authentication, provide the Dial-out Login and Dial-out Password as authentication tokens. Once authenticated, a PPP session will be established using either negotiated IP addresses or specific IP addresses (determined by the Negotiate IP Address setting).  For Dial-on-Demand, the SLC 8000 advanced console manager searches the site list for all sites that (a) have a Dial-out Number defined, (b) have a Static Route IP Address, Static Route Subnet Mask and Static Route Gateway defined, and (c) the Port matches the port the modem is on. A dial-on-demand connection will be started for each, waiting for IP traffic destined for a remote network. When IP traffic needs to be sent, the SLC unit dials the appropriate Dial-out Number for the site, and if the remote peer requests PAP or CHAP authentication, provides the Dial-out Login and Dial-out Password as authentication tokens. Once authenticated, a PPP session will be established using either negotiated IP addresses or specific IP addresses (determined by the Negotiate IP Address setting). The PPP connection will stay active until no IP traffic is sent for Modem Timeout seconds. Once the timeout has expired, the PPP connection will be terminated and will not be reestablished for at least Restart Delay seconds. CBCP Server and CBCP Client Callback Control Protocol (CBCP) is a PPP option that negotiates the use of callback where the server, after authenticating the client, terminates the connection and calls the client back at a phone number that is determined by the CBCP handshake. For more information on CBCP, see http://technet.microsoft.com/en-us/library/cc957979.aspx. CBCP is used primarily by Microsoft PPP peers. CBCP supports two options for determining the number to dial on callback: the client can specify a user-defined number for the server to dial on callback, or the client can request the server use an administrator-defined number to dial on callback. Optionally, some servers may also allow "no callback" as an option. CBCP Server SLC™ 8000 Advanced Console Manager User Guide 257