a client currently has a /23 PI space where the route-object is currently managed by ISP-A we want to split the PI space into two /24's but not certain on how best to go about this.

  • ISP-A will use the 1st /24 for legacy internet services
  • ISP-B will break the currently unused /24 out of the parent /23 route object to provide new more cost effective internet services.

    1. how is this done ? does the client make a request to ISP-A (the current route maintainer mtn-by) , which in turn then makes the request to the Registrar which then either creates two new /24 route objects or just delegates ISP-B mnt-lower access to enable them to advertise the prefix.

    2. What do the below field mean in relevance to my question

      • aut-num:
      • mnt-lower:
      • mnt-routes:
      • mnt-by
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    – Ron Maupin
    Jan 5 at 1:22

I use 2 ISPs and my agreement with them is they will not take less than a /24 so I can divide my address space any way I want as long as my prefixes are long than /24, so I don't think you need (or want to change the registration) just advertise 1 /24 to ISP A and the other to ISP B. Now the ISPs may be filtering only on the prefix you expect to send so you need to check with the ISPs on their route policy.

But this assumes that you really own the /23 space directly form the registry not from a ISP.

  • Both ISPs need to be able to take the /23 for redundancy or at least accept both /24s. Jul 17 '13 at 5:37
  • 1
    You definitely should create route objects for each prefix you announce.
    – ytti
    Jul 17 '13 at 10:54

Which RIR is the PI space from? In RIPE-land, a PI resource can currently only be used by the organisation it is assigned to, for their own purposes. "Sub-assignments" are not allowed. For other registries, the policies may differ somewhat.

  • it is RIPE registered space
    – DrBru
    Jul 17 '13 at 14:49

Pragmatically speaking, nothing needs to be done at the RIR, you just announce the /24 from whereeveand you're done.

Good practice, on the other hand dictates that you should create a new route object for this /24 at the RIR that specifies the origin AS etc.

Since the ISP is the maintainer of the object, it's their responsibility to do that.

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