[j-nsp] MPLS load balancing hash-key

[Hannes Gredler]

On Thu, May 22, 2003 at 02:27:45PM +1000, Dmitri Kalintsev wrote:
| On Tue, May 20, 2003 at 07:04:28AM -0700, Paul Goyette wrote:
| > No.
| > 
| > MPLS packets are hashed using only the MPLS hash key.  MPLS packets
| > are not further inspected to determine if the encapsulated data is
| > an IP packet or something else.
| 
| ...which sucks. :) Other vendor's equipment is actually looking beyound the
| shim header and uses IP header data for LB hash (not sure about non-IP).
| Other vendor's bucket algorithm does not always provide nice load spreading,
| too, but it's still better that Juniper's one (especially when there's not
| enough egress labels for the algorithm to start working acceptably). (I'm
| *not* advocating the other vendor, don't get me wrong). But hey - you can't
| have your cake and eat it, too (which is a shame anyway). ;)

which will draw up the question:
how does a core LSR really know that the payload is IPv4 ?
crawling through the stack and looking to 0x45 - 0x4f
after a label with BOS bit set alike fingerprints, gives a
high likelyhood that the payload is indeed IPv4, however you'll
never _know_;

if you need MPLS-deep-crawling functionality for load balancing
purposes pls talk to your local sales team, they can give you
our view plus our roadmap in this space;

/hannes