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New Member

IP Broadcast Address 0.0.0.0

We recently upgraded to a 7606 with an MFRC in our core.

Everything routed through was successfully permitted to leave the LAN into the WAN. However, all directly connected networks were not permitted access to the WAN.

There was a line reading

IP Broadcast-Address 0.0.0.0

When it was removed the directly connected networks were permitted access to the WAN.

What does setting your IP Broadcast-Address to 0.0.0.0 accomplish for you? I found a reference regarding IPSEC and DF, but nothing else.

Thank You

1 REPLY
New Member

Re: IP Broadcast Address 0.0.0.0

This command is used to make the broadcast address as 0.0.0.0 instead of 255.255.255.255.This command was usedonly in older days.Now this is obselete ,if my understanding is correct.Although current IP implementations use a broadcast address of all ones, the first IP implementations used a broadcast address of all zeros. Many of the early implementations do not recognize broadcast addresses of all ones and fail to respond to the broadcast correctly. Other early implementations forward broadcasts of all ones, which causes a serious network overload known as a broadcast storm. Implementations that exhibit these problems include systems based on versions of BSD UNIX prior to Version 4.3.

You can go thru the following URLs :

http://www.cisco.com/univercd/cc/td/doc/cisintwk/ics/cs006.htm

http://www.cisco.com/univercd/cc/td/doc/product/software/ios121/121cgcr/ip_c/ipcprt1/1cdipadr.htm#xtocid47

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