Multi-Tech MultiFRAD 200 Series, Руководство пользователя

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Chapter 4 - MultiFRAD Software
IP Statistics
IP is a connection-less network protocol that resides in the network layer of a conventional OSI
layered model (for more information on this model, refer to Appendix C). Depending on what is going
on at the application layer, IP will typically use one of two transport layer protocols. User Datagram
Protocol (UDP), is a connection-less transport layer protocol used with TFTP or SNMP; and
Transport Control Protocol (TCP) is a connection-oriented transport layer protocol used with FTP,
Telnet, and SMTP.
UDP makes use of the port concept and has no measures for flow control, reliability, or error
recovery. It is used when the full services of TCP are not required, and the reliability measures must
be assumed by another layer.
TCP works well in environments where the reliability measures are not assumed by other layers. It is
connection-oriented and has a full range of services.
These statistics are primarily informational, and their use as a troubleshooting tool will be contingent
on the applications running in the upper layers. For instance, if you were having problems connecting
to MultiFRAD’s Web server, you would look under the TCP section to make sure connections are
being established. If not, perhaps the Web server is not enabled. Or, if you were having problems
establishing a remote connection through TFTP, you could look in the UDP section to see if any
packets are being received. If not, you may need to review your network addressing.
The Port Tab enables you to view generic IP statistics for a given Ethernet IP Port. The statistics for
either the Ethernet (LAN) port or any logical IP WAN port can be viewed in this window. The
practicality of statistical use in troubleshooting will depend on the application running in the upper
layers.