Dial-Up Ports for Primary and Backup Links. The dial-up features allow you to configure certain ports for dial-up mode.

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1 encor! enetworks TM Version A, January Encore Networks, Inc. All rights reserved. Dial-Up Ports for Primary and Backup Links The dial-up features allow you to configure certain ports for dial-up mode. 7.1 Typical Applications Modems can be used to back up an existing link or to provide a primary dial-up connection Primary Dial-Up Connections Examples of primary dial-up connections include accessing or the Internet by logging onto or off of a server. In Figure 7-1, remote users can access the Internet via dial-up connections to the FRAD. The FRAD can then carry the traffic over Frame Relay to the ISP. If the remote users are using modems, the Network would be a POTS network. For information on trademarks, safety, limitations of liability, and similar topics, see Notices. Home Module: Port Configuration Document 7

2 Page 2 Port Configuration Module, Document 7 ISP Frame Relay Mike StandAlone PC Network FRAD TIM Local Area Network Dial Backup Connections Figure 7-1. Accessing the Internet via Dial-up Connection External dial devices such as modems can serve as a backup link for a Frame Relay connection. If the unit detects that the primary Frame Relay link is down, it automatically establishes a backup modem connection to replace the trunk that is down. The connection remains up until the primary link is reestablished and stable, at which time the backup link is disconnected. In this manner, the link guards against possible data loss or interruption, making your network more stable and reliable. In Figure 7-2, the primary Frame Relay link from Unit 1 to Unit 2 can be backed up by a modem. This example shows traffic going through an ISDN network to Unit 2. However, you could also send traffic through a modem instead of through the ISDN network. The modem would link directly to Unit 2. If the primary Frame Relay link goes down, the ISDN port device or modem dials out to Unit 2, using the phone number(s) you entered. Once connected with Unit 2, Frame Relay data can be sent across the backup link.

3 Dial-Up Ports for Primary and Backup Links Page Unit Frame Relay ISDN DLCI 17 Unit Figure 7-2. Backing Up Frame Relay via ISDN or Modem Assigning a Priority Level to a Backup Link Figure 7-3 shows a primary Frame Relay link and a backup ISDN link from Unit 1 to Unit 2, and a dial-up ISDN link to the Internet through an MLP port. The MLP port consists of two ISDN channels. These two Internet-destined ISDN channels consume the available bandwidth of that line. However, when data must be sent across the backup link, you can ensure that the backup link has sufficient bandwidth by assigning a higher priority to the backup port and a lower priority to at least one of the MLP member ports. When a backup link is needed, the call with the lower priority level that is going out on a multilink port is cancelled, and Frame Relay traffic is given priority over the ISDN line (or modem). Note: You could also send traffic through a modem instead of through the ISDN network to reach Unit 2.

4 Page 4 Port Configuration Module, Document Unit 2 Frame Relay MLP ISDN ISDN ISP DLCI 17 Unit Figure 7-3. Assigning Priority to a Backup Link 7.2 Primary and Backup Link Procedures for Modems You can configure primary and backup links via modem. See the following sections: Primary and Backup Links via Modem Configuring Basic Dial-Up Properties Primary and Backup Links via Modem 1 Configure the port to which you will attach the modem. Follow the procedures in: Selecting a Logical Port Selecting a Protocol Specifying the Port s Global Path Configuring Basic Dial-Up Properties 2 Configure a port for a primary link, such as. See the procedure for the protocol you are using for this port. See the Protocols Module for protocols used in the BANDIT devices. 3 Make an entry in IP Routing s RIP Interface Table for the port with the primary link. In the IP Address field, enter the IP address you are assigning to this port. In the Enter BackUp Interface IP Address field, enter the IP address you assigned to the modem backup port in the IP Address field of the RIP Interface Table. 4 Make an entry in IP Routing s RIP Interface Table for the modem backup port. In the IP Address field, enter the IP address you are assigning to this port. In the Enter BackUp Interface IP Address field, enter

5 Dial-Up Ports for Primary and Backup Links Page Configuring Basic Dial-Up Properties Note: You can assign dial-up properties to the Modem port or to a port that is configured for async or async Frame Relay. 1 On the Main Menu, select Advanced Configurations. The Advanced Configurations menu appears. 2 On the Advanced Configurations menu, select Data Configurations. The Logical Port Statistics menu appears. 3 Select a port for dialup properties, such as the Modem port or an async protocol with dialup (for example, async Frame Relay). The port s Logical Port Attribute menu appears. 4 Select Dialup Configuration. The Dialup Configuration menu is displayed with the port number you defined as a dial-up port. Dialup Configuration : MODEM ) Dial Mode : ANSWER 2) Primary Phone Number : 3) Secondary Phone Number : 4) Redial Timer Seconds : 10 5) Number of Redials : 200 6) Dialup Port Priority : Low 7) Toll Saver : Disabled 8) Toll Saver Timeout : 180 9) Maximum Number of Successful Calls Allowed In a Minute : 3 Enter Choice : 5 Select Dial Mode. The Configure Dial Mode menu is displayed: Configure Dial Mode ) DIALOUT 2) ANSWER 3) DIALOUT/DIALIN Enter Choice : a Select Dial Out if this port will always initiate the call process whenever data needs to be sent. Note: You must configure the other unit to Answer incoming calls. b Select Answer to allow the port to accept incoming calls.

6 Page 6 Port Configuration Module, Document 7 Note: You must configure the other unit(s) to Call Out. c Select Dialout/Dialin to allow this port both to send and to receive calls. 6 Select Primary Phone Number if the port is configured for Dialout Mode. This option allows you to specify the first number that should be dialed when a connection is necessary. Enter Primary Phone Number: 7 Enter the phone number to be dialed first and press Enter. 8 If the port is configured for Dialout Mode, select Secondary Phone Number. This option allows you to specify a number that should be dialed when the primary number is busy or not in service. Enter Secondary Phone Number: 9 Enter the phone number to be dialed second and press Enter. 10 If the port is configured for Dialout Mode, select Redial Timer. This option allows you to specify the number of seconds the port waits before retrying the call. Enter Redial Timer (0-180 sec): 11 Enter the number of seconds the unit must wait before retrying the call, and press Enter. 12 If the port is configured for Dialout Mode, select Number of Redials. This option specifies the number of times the modem attempts a connection. (If you have defined both a primary and a secondary number, the modem alternates attempts with the primary and secondary numbers.) Enter Number of Redials (0-99): 13 Enter the number of times the unit can attempt to make a connection before it gives up, and press Enter.

7 Dial-Up Ports for Primary and Backup Links Page 7 14 Select Dialup Port Priority. This option allows you to assign a priority level to a dial-up port, so that if another dial-up port with a higher priority requests a connection, the dial device will disconnect the lower priority call and connect the higher one. If an answering application has the highest priority, the dial device will place itself in answer mode. If there are many answering applications per dial device, the incoming call always goes to the highest-priority answering application. If there are several applications with the same priority contending for the dial device, the application that requests the dial device first is the first one served. As applications compete for the dial device, the priority feature allows high-priority activities to preempt lower-priority activities. The screen displays the Configure Dialup Port Priority menu: Configure Dialup Port Priority ) LOW 2) MEDIUM 3) HIGH Enter Choice : 15 Select the priority level for this traffic. 16 Select Toll Saver to enable or disable Toll Saver mode. Toll Saver automatically disconnects the dial-up link if no data is transmitted within a specified number of seconds. The link is re-established, however, when data arrives at the port. The following menu options are displayed: Configure Toll Saver ) Enabled 2) Disabled Enter Choice: 17 Select the mode you want. a Select Enabled if you want the link to be disconnected whenever the line remains idle for a specified amount of time. This mode reduces the cost of line usage. b Select Disabled if you do not want the link to be disconnected based on idle time. 18 If you disabled Toll Saver, proceed to Step If you enabled Toll Saver, you must specify the number of seconds the line may remain idle before it is automatically disconnected. Select Toll Saver Time Out. The following prompt is displayed.

8 Page 8 Port Configuration Module, Document 7 Enter Toll Saver Timeout ( sec): 20 Enter the desired number of seconds. 21 Select Maximum Number of Successful Calls Allowed in a Minute to specify the number of successful calls that can be placed within 60 seconds. Enter Maximum Number of Successful Calls Allowed in a Minute (1-25) : Note: This is useful when an application continuously places a call. For example, you can keep the application from continually dialing by setting the maximum number of successful calls allowed per minute to 3. Then, after three successful calls, the application will not attempt another call until one minute after the first call had succeeded. 22 Enter the maximum number of successful calls to allow in one minute, and press Enter.