EasyManuals Logo

Cisco Catalyst 3560-X User Manual

Cisco Catalyst 3560-X
1538 pages
To Next Page IconTo Next Page
To Next Page IconTo Next Page
To Previous Page IconTo Previous Page
To Previous Page IconTo Previous Page
Page #1061 background imageLoading...
Page #1061 background image
1-15
Catalyst 3750-X and 3560-X Switch Software Configuration Guide
OL-25303-03
Chapter 1 Configuring IP Unicast Routing
Configuring IP Addressing
Configuring Broadcast Packet Handling
After configuring an IP interface address, you can enable routing and configure one or more routing
protocols, or you can configure the way the switch responds to network broadcasts. A broadcast is a data
packet destined for all hosts on a physical network. The switch supports two kinds of broadcasting:
A directed broadcast packet is sent to a specific network or series of networks. A directed broadcast
address includes the network or subnet fields.
A flooded broadcast packet is sent to every network.
Note You can also limit broadcast, unicast, and multicast traffic on Layer 2 interfaces by using the
storm-control interface configuration command to set traffic suppression levels. For more information,
see Chapter 1, “Configuring Port-Based Traffic Control.
Routers provide some protection from broadcast storms by limiting their extent to the local cable.
Bridges (including intelligent bridges), because they are Layer 2 devices, forward broadcasts to all
network segments, thus propagating broadcast storms. The best solution to the broadcast storm problem
is to use a single broadcast address scheme on a network. In most modern IP implementations, you can
set the address to be used as the broadcast address. Many implementations, including the one in the
switch, support several addressing schemes for forwarding broadcast messages.
Perform the tasks in these sections to enable these schemes:
Enabling Directed Broadcast-to-Physical Broadcast Translation, page 1-15
Forwarding UDP Broadcast Packets and Protocols, page 1-16
Establishing an IP Broadcast Address, page 1-17
Flooding IP Broadcasts, page 1-18
Enabling Directed Broadcast-to-Physical Broadcast Translation
By default, IP directed broadcasts are dropped; they are not forwarded. Dropping IP-directed broadcasts
makes routers less susceptible to denial-of-service attacks.
You can enable forwarding of IP-directed broadcasts on an interface where the broadcast becomes a
physical (MAC-layer) broadcast. Only those protocols configured by using the ip forward-protocol
global configuration command are forwarded.
You can specify an access list to control which broadcasts are forwarded. When an access list is
specified, only those IP packets permitted by the access list are eligible to be translated from directed
broadcasts to physical broadcasts. For more information on access lists, see Chapter 1, “Configuring
Network Security with ACLs.
Beginning in privileged EXEC mode, follow these steps to enable forwarding of IP-directed broadcasts
on an interface:
Command Purpose
Step 1
configure terminal Enter global configuration mode.
Step 2
interface interface-id Enter interface configuration mode, and specify the interface to
configure.

Table of Contents

Questions and Answers:

Question and Answer IconNeed help?

Do you have a question about the Cisco Catalyst 3560-X and is the answer not in the manual?

Cisco Catalyst 3560-X Specifications

General IconGeneral
Enclosure TypeRack-mountable - 1U
SubtypeGigabit Ethernet
Ports48 x 10/100/1000 + 4 x SFP
Flash Memory64 MB
Power DeviceInternal power supply
Voltage RequiredAC 120/230 V (50/60 Hz)
Operating SystemCisco IOS
Device TypeSwitch
PerformanceSwitching capacity: 128 Gbps
Jumbo Frame SupportYes
Routing ProtocolRIP-1, RIP-2, EIGRP
Remote Management ProtocolSNMP 1, RMON 1, RMON 2, RMON 3, RMON 9, Telnet, SNMP 3, HTTP, HTTPS
FeaturesDHCP support, VLAN support, QoS, IPv6 support, Syslog
Compliant StandardsIEEE 802.3, IEEE 802.3u, IEEE 802.3z, IEEE 802.1D, IEEE 802.1Q, IEEE 802.3ab, IEEE 802.1p, IEEE 802.3af, IEEE 802.3x, IEEE 802.3ad, IEEE 802.1w, IEEE 802.1x, IEEE 802.1s, IEEE 802.3ah, IEEE 802.1ag, IEEE 802.3at
StackingStackable
Security FeaturesSSH, RADIUS, TACACS+
ManagementCLI
Dimensions (H x W x D)17.5 in
Operating Temperature32 to 113 °F (0 to 45 °C)
Humidity10 - 95% (non-condensing)

Related product manuals