Security4-6 7112-A2-GB20-20March 1998Table 4-2. ATI Access Conditions (2 of 2)If access to the ATIis through the . . . What to do now?Then . . .Terminal port and theATI is already in usewith a Telnet sessionUser Interface AlreadyIn Use message appearswith the active user’s IPaddress and Login ID.Try again later.When the ATI is available, themessage User Interface Idleappears. Press Enter for the MainMenu.Telnet session and theATI is currently in useConnection Failedmessage appears. TheDSU/CSU allows onlyone ATI session.Try again later.Controlling SNMP AccessThere are three methods for limiting SNMP access. Disable the SNMP management option. Assign SNMP community names and access levels. The DSU/CSU supportsSNMP Version 1, which provides limited security through the use ofcommunity names. Limit SNMP access through validation of the IP address of each allowedSNMP manager.Assigning SNMP Community Names and Access LevelsThe DSU/CSU can be managed by an SNMP manager supporting the SNMPprotocol. The community name must be supplied by an external SNMP manageraccessing an object in the MIB.To define SNMP community names, follow this menu selection sequence:Main Menu →Configuration →(Load Configuration From) →SNMP →General SNMP ManagementRefer to Table A-8, General SNMP Management Options, to: Enable SNMP Management. Assign the SNMP community names of the SNMP Managers that are allowedto access the DSU/CSU’s Management Information Base (MIB). Specify read or read-write access for each SNMP community name.
