UDP broadcast from an XO

[david at lang.hm]

On Fri, 2 Jan 2009, shivaprasad javali wrote:

> Hi,
>   Is there any way I can ask the OLPC to broadcast the UDP packets. I am
> broadcasting the UDP packets by writing to the UDP port and setting the
> destination address to 255.255.255.255 . I am using ports 61556 and 61557
> for communication. So if the antenna of the OLPC ( and hence its wireless
> connectivity) is functional wont it broadcast the UDP packets it receives
> for broadcast?

the normal address to use for broadcasts is nto 255.255.255.255, but the 
broadcast address of the particular network you are on.

for example: if you are on 192.168.1.0 with a netmask of 255.255.255.0 the 
broadcast address would be 192.168.1.255

David Lang

> Thanks
> jbsp72
>
> On Fri, Jan 2, 2009 at 1:30 PM, <david at lang.hm> wrote:
>
>> On Fri, 2 Jan 2009, quozl at laptop.org wrote:
>>
>>  Visibility in Neighbourhood View is determined by access from the XO to
>>> the Jabber server.  The Jabber server does not relay these UDP packets
>>> for you.  Therefore visibility is not an indicator of ability to operate
>>> over UDP.
>>>
>>> A wireless router will relay the UDP packets.  The relay is being done
>>> by the router itself, and so any XO not associated with the router may
>>> not receive the UDP packets unless the packets are forwarded by the
>>> router to whatever router the other XO is associated with.
>>>
>>> Can you show me one of these UDP packets?
>>>
>>
>> remember that broadcast packets don't generally go through routers (they go
>> through bridges, but not routers)
>>
>> so if the two XO's are on different subnets, broadcasts won't be seen by
>> the other one.
>>
>> David Lang
>>
>