Newbies Question: Do I really need to sacrifice Prefix-aggregation to do BGP Load-sharing?

Pirawat WATANAPONGSE pirawat.w at
Thu Oct 20 12:13:13 UTC 2022

Dear all,

Before all else:
thank you all for the lightning-fast responses (even taking the time zone
advantage into account).
I really, really, really appreciate all your recommendations.

Virtually all of you recommend prepending as the first choice.
I also get the feeling that you guys consider de-aggregation “distasteful”
(at the least) but sometimes unavoidable.

I have considered the prepending myself, but dare not implement it yet
for the fear that BGP (Human) Community will burn me alive, witch-hunt
because of the following reasons:
1. I can see from looking glass(es) that my upstreams already practice
prepending (some paths) at their level (at least 3 more hops [x4]),
supposedly to “balance” their bandwidth.
2. Should I start prepending mine, I might upset their balance, causing
them to prepend more, thus starting a “prepend war”. [I imagine that x20+
prepending starts out this way]

The way I see it, prepending (or maybe even the whole BGP-Path thing) is a
local-optimization problem: it’s only best for someone, not globally.
And the Higher-Tiers (Lower Tier-Numbers) will always “engineer” me in the

Worse yet, I might be out-voted by de-aggregation insider “cultists” anyway.

Which forces me to proactively ask you guys questions about ROV-Overlapping
and ROV “Hijack Gap” soon, in another posting with separate “Subject:”.

Again, Thank you.



P.S.  [Off-Topic] Any comment on the “SCION” System?
Any good (I will even take "academically")?
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