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FTP
File Transfer Protocol (FTP) is an application layer protocol for transferring files from one host to
another over an IP network. It uses TCP port 20 to transfer data and TCP port 21 to transfer control
commands.
The device can act as the FTP server.
Telnet
The device can act as a Telnet server to allow Telnet login. After you configure Telnet service on the
device, users can remotely log in to the device to manage and monitor the device.
To prevent unauthorized Telnet logins, you can use ACLs to filter Telnet logins.
•
If you does not specify an ACL for Telnet service, or the specified ACL does not exist or does not
have rules, the device permits all Telnet logins.
•
If the specified ACL has rules, only users permitted by the ACL can Telnet to the device.
NTP
Synchronize your device with a trusted time source by using the Network Time Protocol (NTP) or
changing the system time before you run it on a live network.
NTP uses stratum to define the accuracy of each server. The value is in the range of 1 to 15. A
smaller value represents a higher accuracy.
If the devices in a network cannot synchronize to an authoritative time source, you can perform the
following tasks:
•
Select a device that has a relatively accurate clock from the network.
•
Use the local clock of the device as the reference clock to synchronize other devices in the
network.
You can configure the local clock as a reference clock in the Web interface.
SNMP
Simple Network Management Protocol (SNMP) is an Internet standard protocol widely used for a
network management station (NMS) to access and manage the devices (agents) on a network. After
you enable SNMP on the device, the device acts as an SNMP agent.
SNMP enables an NMS to read and set the values of the variables on an agent. The agent sends
traps to report events to the NMS.
MIB
Management Information Base (MIB) is a collection of objects. It defines hierarchical relations
between objects and object properties, including object name, access privilege, and data type.
An NMS manages a device by reading and setting the values of variables (for example, interface
status and CPU usage) on the device. These variables are objects in the MIB.
