Re: NBMA ....IGP DOUBTS

To answer question number 3, the broadcast keyword as I understand it, instructs the router to forward broadcast/multicast traffic to the other router as unicast traffic. This allows routing protocols to form adjacencies without the use of the neighbor statement.

Or at least that's the way I understand it, experts please correct me if I'm wrong on this point.

Sent from my iPad

On Jul 16, 2011, at 12:15 PM, marc abel <marcabel_at_gmail.com> wrote:

> NBMA mode deos not support broadcasts by default, so routing protocols
> that use broadcast/multicast to communicate will not form adjacency.
> Using frame-relay interface-dlci or the broadcast option on a static
> frame map gets around this. If you don't have this, then you will need
> neighbor statements.
>
> If you specifiy the OSPF network type as broadcast you are signalling
> two things. 1. That you expect to elect a DR and 2. That you will be
> using "fast" timers 10/40 seconds.
>
>
>
> On Sat, Jul 16, 2011 at 12:02 PM, imran ali <immrccie_at_gmail.com> wrote:
>> HI experts
>>
>> 1 )since NBMA does not support multicast ..then how are we able to form
>> adjacency on it ..for example rip and eigrp ..just turn the interface on and
>> neighbors will come up .....without any need to configure neighbor commands
>> ... is it that protocol has inbult features that sense underlying frame
>> relay media and begins unicasting the neighbors as RIP and eigrp dont
>> require " classical neighbor commands" as required by OSPF ...
>>
>>
>> 2) on a frame network if we specify OSPF network type as " broadcast" does
>> this turns the frame network that natively dosent support broadcast ...to
>> suddenly start supporting broadcast ....
>>
>> 3) whats the funda with " broadcast " key word in frame relay static maps
>> ... whats differce will it create if i dint specify it ...
>>
>> my routing protocols will not work if i dint specify it ?
>>
>>
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Received on Sat Jul 16 2011 - 12:35:24 ART