From: Arun Kumar Arumuganainar (aarumuga@hotmail.com)
Date: Sun Jul 10 2005 - 08:44:05 GMT-3
For Fram Relay Networks , Default Mode in Frame Relay Network is NBMA .
But this will work only with Fully Meshed network .In Hub and Spoke
topology full connectivity can not be achived . Spoke routers will only
be able to ping Hub router and none of the other spoke routers.
Note :In the above scenario OSPF neighborship will get established .
Routing table will get populated as normal . But however , connectivity
alone will not be there across the Spokes .This Problem will also be seen
in Partially meshed networks as well .
By making the Network type Point to Multipoint you can over come this
problem . Actually if you inspect the routing table on the point to
Multipoint network , you will be able to observe host route ( Route with
/32 Bit mask ) for all connected IP address . This will enable routing
possible between spokes !!!
Pls. Note : You could add broadcast keyword appended to point to
Multipoint . In case you are not allowed to configure broadcast key word
then you will have manually configure neighbour statement . This will
enable OSPF packets to unicasted over the FR Cloud .
Hope this helps.
Thanks and Regards
Arun
>From: Sila Moni <silamoni@yahoo.com>
>Reply-To: Sila Moni <silamoni@yahoo.com>
>To: Amit Jain <netsteps@rediffmail.com>, Group Study <>
>Subject: Re: IE Lab15 Task 5.21
>Date: Sat, 9 Jul 2005 05:52:29 -0700 (PDT)
>
>There are two issues that I see from this scenario.
>
>1. Typically, you would use the neighbor statement on
>the hub. Since it is on R3 (spoke), it will create
>some problems. Are you allowed to put the neighbor
>statement on R4 as well?
>
>2. P-T-M non-broadcast is used in NBMA with virtual
>circuits of differing speeds (e.g. ISDN and FR).
>Here, assigning cost to the neighbor is optional.
>
>
>--- Amit Jain <netsteps@rediffmail.com> wrote:
>
> > Hi
> >
> > In the task, R3 and R5 are connected through frame
> > relay and R4 and R5 through
> > ISDN
> >
> > R3
> > -
> > -
> > - FR -
> > -
> >
> > R4 - -ISDN - - R5
> >
> > Now the ospf area 345 is running on FR and ISDN
> > links and network type
> > non-broadcast between R3 and R5, with neighbor
> > command on R3.
> > Task requirement is to configure all adjacencies in
> > area 345 in such a manner
> > that other devices on segment cannot recieve OSPF
> > hello packets.
> > The solution given is that the network type on ISDN
> > and FR segment be changed
> > to point-to-multipoint (with ofcourse neighbor
> > statements)
> >
> > My ques is why we need to change it to
> > point-to-multpoint from non-broadcast
> > on FR segment ? When the netwrk type is
> > non-broadcast we are sending packets
> > as unicast only, so why specifically change to
> > p-to-multipoint ?? (Only
> > difference will be no DR/BDR elec and host route)
> >
> > Also the ISDN segment is network type point-to-point
> > so anyways the hello
> > packets will only go to the other side ?? What am i
> > missing.
> >
> > Could not get the answer from IE website posts.
> >
> > Thanks
> > Amit Jain
> >
> >
>_______________________________________________________________________
> > Subscription information may be found at:
> > http://www.groupstudy.com/list/CCIELab.html
> >
>
>
>
>
>____________________________________________________
>Sell on Yahoo! Auctions no fees. Bid on great items.
>http://auctions.yahoo.com/
>
>_______________________________________________________________________
>Subscription information may be found at:
>http://www.groupstudy.com/list/CCIELab.html
------------------------------------------------------------------------
Looking for a date? Meet interesting singles like you Sign up with
Match.com
This archive was generated by hypermail 2.1.4 : Sun Sep 04 2005 - 17:00:29 GMT-3