Question : Frame Relay configuration on Hub & Spoke Router network

The attached picture shown that it is Hub-Spoke Router on Frame Relay Network .

R1 and R2 are spoke routers , these 2 routers never directly connect to each other .

R1 is connected directly to R3 , R2 is connected directly to R3 too.  R3 is acting as "hub Router".

In order to make R2  to reach R1 , I refer to some tutorial/book and I am confused on one point .

In order to make R2 to reach R1 , the book suggest the following command :-

Of course we should configure R1 and R3 too , but I skip the cofiguration on R1 and R3 and just take R2 as example .

R2(config-if)# interface s0.123 multipoint
R2(config-subin)#ip address
R2(config-subif)#frame map ip 203 broadcast
R2(config-subif)#frame map ip 203

By having above command , R2 can reach R3 and also can reach R1 .

What I am confused is WHY we can use SAME DLCI (203) to reach 2 difference destinations ??
I though DLCI is Local significant ???

Is it because we configure it as multipoint interface (subinterface) , so we can use SAME LOCAL DLCI to map on difference remote address ???
HUb-Spoke FRAME RELAY network

Answer : Frame Relay configuration on Hub & Spoke Router network

You are correct that in p2p networks, you cannot use the same DLCI value to map difference remote address via separate subinterfaces. The key difference with multipoint FR is that, unlike p2p subinterfaces, the frame-relay interface-dlci command can be configured multiple times to associate more than one DLCI to THE SAME multipoint subinterface. What's confusing you, I think, is that the second address being mapped in your R2 example is a BROADCAST address. On a multipoint subinterface, either the "frame-relay interface-dlci dlci" or frame-relay map protocol protocol-address dlci [broadcast]" commands can be used to associate the multipoint subinterface with specific DLCIs. The "frame-relay interface-dlci dlci" command performs dynamic address mapping using Inverse ARP to map the next-hop protocol address to the local DLCI on the router.

The key is to understand that multipoint FR networks can use broadcasts to direct traffic to a specific remote node. That is what is happening in your example.
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