Alcatel-Lucent 6850-48 ネットワークガイド

Configuring IP

IP Overview

OmniSwitch AOS Release 6 Network Configuration Guide

page 24-5

IP is a network-layer (Layer 3) protocol that contains addressing and control information that enables 
packets to be forwarded on a network. IP is the primary network-layer protocol in the Internet protocol 
suite. Along with TCP, IP represents the heart of the Internet protocols. 

IP is associated with several Layer 3 and Layer 4 protocols. These protocols are built into the base code 
loaded on the switch. A brief overview of supported IP protocols is included below.

IP is both connectionless (it forwards each datagram separately) and unreliable (it does not guarantee 
delivery of datagrams). This means that a datagram may be damaged in transit, thrown away by a busy 
switch, or simply never make it to its destination. The resolution of these transit problems is to use a Layer 
4 transport protocol, such as:

• TCP—A major data transport mechanism that provides reliable, connection-oriented, full-duplex data 

streams. While the role of TCP is to add reliability to IP, TCP relies upon IP to do the actual deliver-
ing of datagrams.

• UDP—A secondary transport-layer protocol that uses IP for delivery. UDP is not connection-oriented 

and does not provide reliable end-to-end delivery of datagrams. But some applications can safely use 
UDP to send datagrams that do not require the extra overhead added by TCP. For more information on 
UDP, see 

Application-layer protocols are used for switch configuration and management:

• Bootstrap Protocol (BOOTP)/Dynamic Host Configuration Protocol (DHCP)—May be used by an end 

station to obtain an IP address. The switch provides a DHCP Relay that allows BOOTP requests/replies 
to cross different networks.

• Simple Network Management Protocol (SNMP)—Allows communication between SNMP managers 

and SNMP agents on an IP network. Network administrators use SNMP to monitor network perfor-
mance and manage network resources. For more information, see the “Using SNMP” chapter in the 
OmniSwitch AOS Release 6 Switch Management Guide.

• Telnet—Used for remote connections to a device. You can telnet to a switch and configure the switch 

and the network by using the CLI.

• File Transfer Protocol (FTP)—Enables the transfer of files between hosts. This protocol is used to load 

new images onto the switch.