Re: Fragment : 2nd Ques

- fragments can take different routes, hence intermediate router may not
have all information required for reassembly
- reassembly requires wait time till all the fragments are received, this
would be time consuming and burden on all intermediate routers performing
reassembly rather than forwarding packets to destination

Ofcourse the drawback is smaller fragments being transmitted between
intermediate routers even though there WAN link has higher capacity.

On Tue, Sep 21, 2010 at 11:03 AM, Happy Singh <
happynetworkingsingh_at_gmail.com> wrote:

> Hi
>
> Again ; trying to understand Fragmentation .
> Lets have following scenario :
>
> R1 --------R2 ------------R3 ----R4
>
> R1-R2 MTU = 3300 bytes
> R2-R3 MTU = 1300 bytes
> R3-R4 MTU = 3300 bytes
>
>
> Let pkt of 12000 byte came in R1 . It fragments and send on R1-R2 link
>
> R2 must fragment each of these into smaller fragments to send them over
> the
> 1,300-byte MTU link. Note that the R3 does *not* reassemble the
> 1,300-byte fragments, even though next link has an MTU of 3,300
> bytes.WHYYYYYY ????
>
> My question is that why is re-assembly done by end router ? Reasons ?
>
> Thnx
> Happy
>
>
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-- 
Hi
Rgds,
It does not mean a thing, if it can't make a ping!! :-)
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