Laszln, Thu, Apr 28, 2016 at 12:47:45PM +0000, Laszlo Hanyecz wrote:
On 2016-04-28 11:06, Alain Hebert wrote:
Well,
Once you eliminate the ~160k superfluous prefixes (last time I checked)... This is a none issue.
Some work on some sort summary function would keep those devices alive... but we all know there is more money to be made the faster the device become obsolete :(
Can you explain how this works? How can a router determine which prefix is superfluous? How does it cope when a suppressed prefix is withdrawn or a more specific prefix is added? Is this just one of those 'it works some of the time' solutions or is this something that can be done safely with an appropriate algorithm?
A fair chunk of the routing table is aggregable. If multiple aggregable prefixes share the same nexthop, the HW entries can be summarised accordingly, reducing the HW resource footprint. Should one of the smaller prefixes be withdrawn or best path change to another nexthop, the control plane needs to be smart enough to adapt and reprogram the HW accordingly. It is a fairly logical and reasonable algorithm to construct -- Patrick Cole <z@wwwires.com> Senior Network Specialist World Without Wires PO Box 869. Palm Beach, QLD, 4221 Ph: 0410 626 630