- Read Me First
- What's New in Cisco IOS XE (SD-WAN)
- Cisco Catalyst SD-WAN Basic System Overview
- Configure System Logging
- Configure User Access and Authentication
- Role Based Access Control
- Role-Based Access Control (Cisco IOS XE Catalyst SD-WAN Release 17.12.x and Earlier)
- Configure Devices
- Device Tagging
- Network Hierarchy and Resource Management
- Cisco Unified Communications Voice Services
- CUBE Configuration
- Configure Network Interfaces
- Hot Standby Router Protocol (HSRP)
- Configure a Cellular Gateway
- Configure Geofencing
- VRRP Interface Tracking
- Configure VDSL and G.SHDSL
- Dynamic On-Demand Tunnels
- Track Static Routes for Service VPNs
- NAT DIA Tracker for Cisco IOS XE Catalyst SD-WAN Devices
- Service-Side NAT on Cisco IOS XE Catalyst SD-WAN Devices
- DHCP Vendor Option Support
- IP DHCP Smart-Relay
- IPv6 Functionality
- IP Directed Broadcast
- Migrate Shared Templates to Cisco IOS XE Catalyst SD-WAN Templates
- CLI Templates for Cisco IOS XE Catalyst SD-WAN Devices
- CLI Add-On Feature Templates
- Cisco Catalyst SD-WAN EtherChannel
- Cisco Catalyst SD-WAN Multitenancy
- Flexible Tenant Placement on Multitenant Cisco Catalyst SD-WAN Controllers
- Multitenant WAN Edge Devices
- Cisco Catalyst SD-WAN Multitenancy (Cisco IOS XE Releases 17.4.x and 17.5.x)
- Cisco Catalyst SD-WAN Carrier Supporting Carrier
- Wireless Management on Cisco 1000 Series Integrated Services Routers
- Extended Visibility with Cisco SD-WAN and Cisco ThousandEyes
- Layer 2 VPN
- Troubleshoot Cisco Catalyst SD-WAN Systems and Interfaces
- Appendix: Cisco SD-WAN Manager How-Tos
IP Directed Broadcast
An IP directed broadcast is an IP packet whose destination address is a valid broadcast address for some IP subnet but which originates from a node that is not itself part of that destination subnet.
A device that is not directly connected to its destination subnet forwards an IP directed broadcast in the same way it would forward unicast IP packets destined to a host on that subnet. When a directed broadcast packet reaches a device that is directly connected to its destination subnet, that packet is broadcast on the destination subnet. The destination address in the IP header of the packet is rewritten to the configured IP broadcast address for the subnet, and the packet is sent as a link-layer broadcast.
If directed broadcast is enabled for an interface, incoming IP packets whose addresses identify them as directed broadcasts intended for the subnet to which that interface is attached are broadcast on that subnet.
Note |
The access control list (ACL) option for directed broadcast is not supported in Cisco SD-WAN Manager. |
To enable the translation of a directed broadcast to physical broadcasts, use the ip directed-broadcast command. To disable this function, use the no form of this command. By default, ip directed-broadcast is disabled and all IP directed broadcasts are dropped.
ip directed-broadcast and no ip directed-broadcastExample
This example shows how to enable forwarding of IP directed broadcasts on Ethernet interface 2/1:
device# configure-transaction
device(config)# interface ethernet 2/1
device(config-if)# ip address 10.114.114.1 255.255.255.0
device(config-if)# ip directed-broadcast
device(config-if)# end