IP Addresses delegated from "NZGATE" in use within New Zealand A description of an addressing issue in New Zealand, and a suggestion of one possible policy to manage it in the future. Fresh copies of this document are available at http://www.patho.gen.nz/~jabley/nznumber.txt The problem at hand ..................................................... 1 Overview ............................................................ 1.1 Issues .............................................................. 1.2 Stability and RFC2050 ........................................... 1.2.1 Impact on end-users ............................................. 1.2.2 Impact on national providers .................................... 1.2.3 Competitive advantage ........................................... 1.2.4 Unified approach .................................................... 1.3 One possible solution ................................................... 2 Overview ............................................................ 2.1 Rationalisation of historical NZGATE delegations .................... 2.2 Classification of actual, existing NZGATE delegations ............... 2.3 Administrative control of NZGATE blocks returned to APNIC ........... 2.4 IN-ADDR.ARPA DNS delegations for NZGATE blocks ...................... 2.5 Forced renumbering .................................................. 2.6 Process for extending address space delegations ..................... 2.7 Process for managing ISP-hopping by operators with "small blocks" ... 2.8 References .............................................................. 3 Netblocks delegated historically to NZGATE-NZ ....................... 3.1 Transition of NZGATE services to other providers .................... 3.2 Various RIPE and APNIC documents .................................... 3.3 Contributors ............................................................ 4 Document History ........................................................ 5 1. The problem at hand 1.1. Overview RFC2050 documents the best current practice for address delegation for the global Internet. It imposes a framework of restrictions driven by a growing scarcity of globally-unique IP addresses and a need to summarise or aggregate routing advertisements globally to keep the Internet running reliably. The history of the Internet in New Zealand includes, at an early stage, a single domestic provider known as "NZGATE". This provider was facilitated by the University of Waikato, with international connectivity to NASA. Initially, NZGATE provided the sum total of international Internet connectivity for New Zealand. The regional authority for IP address allocation, APNIC, delegated a number of address ranges to NZGATE [3.1]. Early entrants to the Internet community in New Zealand, obtaining transit through NZGATE, were delegated address space out of these blocks according to the guidelines set down by APNIC and, indirectly, IANA. NZGATE faded out of existance in 1996 [3.2]. Since that time additional providers have added global internet transit using dedicated international circuits to their portfolio of products, including (in no particular order) Netway, IBM, CLEAR, IHUG, Telstra NZ and Voyager. Most of these participants have obtained address delegations directly from an appropriate regional registry, as they are diversely connected and don't favour a single provider for "default routing". Newly-connected customers of these transit providers (be they end users or resellers, i.e. ISPs) have been delegated provider-aggregatable address space by their providers, from the blocks delegated to those providers from APNIC, according to RFC2050. If these customers change providers, they are obliged to return the address delegations to their old provider, and obtain corresponding new ranges from their new provider. 1.2. Issues 1.2.1. Stability and RFC2050 It is important from a technical standpoint that provider-based aggregation delegation are adhered to for all customers who do not meet the criteria for operating under addresses delegated directly from APNIC. Although there is debatable urgency in how soon a transition is required towards exclusively provider-aggregatable addresses, any solution that involves the number space becoming more fragmented will not scale as the Internet continues to grow. There are reports of longer-prefix advertisements being more enthusiastically damped by core backbone routers in the US, and rumours about possible filtering to refuse transit based on prefix length, within the address ranges under discussion. Although neither of these have been reliably substantiated, there is recognition that these kinds of penalties may well be required in the future to protect global routing stability. 1.2.2. Impact on end-users Renumbering can be an expensive exercise for some end users, especially those whose networks have evolved for some years. In the early days of the Internet in New Zealand, provider-based addressing was not part of the network design. Provider-based addressing first came under discussion as a solution to problems of scale, and only gradually moved from being a radical departure from good practice to an accepted reality. The evolutionary nature of this change was good in the sense that the impact could be somewhat tuned to the timeline of the allocations and expectations, but was bad in the sense that the moving situation added to the complexity and uncertainty. Many established end-user networks were built without the expectation that the IP addresses delegated to them were tied to a particular provider. Now that provider-based addressing is widely recognised as best current practice and is required by the regional registries, the requirement to renumber upon changing provider is still widely misunderstood. It is worth noting that there was no way that NZGATE (or any other ISP at the time) could solve all the issues of address portability raised by the addressing policy changes sweeping across the internet. Many NZGATE-numbered end-users may already have changed providers without renumbering, reinforcing the unfortunate myth that the NZGATE addresses they are using are still inherently portable, and "owned" by them. Although some providers now include clauses in their customer contracts underlining the point that addresses delegated as part of service delivery must be returned at the end of the contract, this is by no means universal, and the myth of "customer-owned IP addresses" lives on. It is imperative going forward that the concept of provider-based addressing and the non-portability of most network numbers is widely publicised amongst end-users. 1.2.3. Impact on national providers For ISPs that obtain global transit through other providers, and who have not arranged address delegations directly from APNIC, renumbering may be just as onerous as for end-users. Additionally national providers may supply end-users for whom renumbering is expensive, and the associated inconvenience mentioned in [1.2.2] is cumulative. ISPs that operate under blocks originally delegated from NZGATE are not as prone to future penalties against long-prefix advertisements as end users, so long as the addresses they used can be aggregated under shorter-prefix supernets. 1.2.4. Competitive advantage There has been a misconception within the NZ Internet community that Netway communications (and, latterly, NetGate/Telecom NZ) assumed the NZGATE role by providing connectivity to the Waikato network in early 1996, and by virtue of this fact the addresses delegated by APNIC to NZGATE are now, by proxy, effectively delegated to Telecom NZ. This does not appear to be a view held by others involved in the "transition" [3.2]. More accurately, for a time Netway was the sole provider to NZGATE, and hence also to all downstream networks of NZGATE. This situation soon changed, with other providers bringing international transit to NZGATE subscribers, and NZGATE slowly faded out of existance leaving end-user networks direct customers of the new international providers. It is not at all obvious that any single provider can lay legitimate claim to operational responsibility of the NZGATE blocks. The effective use of these addresses as "portable" between providers over the past few years is not compatible with a delegation model whereby it is acceptable for NetGate customer networks to use them, but not acceptable for a customer of another provider. In effect, an expectation has been raised by Telecom NZ that customers who have been happily numbered under NZGATE addresses (and have used a variety of ISPs for some time) are now faced with a choice of (a) renumber, or (b) change providers to NetGate/Xtra. Due to the operational cost of renumbering, this gives Telecom NZ competitive advantages over other ISPs based on the contentious belief that Telecom has assumed operational responsibility for the NZGATE address blocks. Many address ranges delegated from the NZGATE blocks, although well documented at the time, have since been unofficially "transferred" to other operators, or are not currently in use. Hence documentation of the current state of NZGATE delegations is out of date. 1.3. Unified approach It is in the interests of all providers within NZ that a solution to the problems outlined in this document be found. It is also important that no single provider is seen to be responsible for what may be seen by end-users as restrictions, or inconvenient changes of policy. By taking a unified approach to the problem with a policy document agreed by the majority of New Zealand providers, the risk of confusion is minimised and the chances of productive user education are increased. It is proposed that the unified policy be agreed as an operational exercise within the provider community, by the usual open discussion within the NZNOG forum. 2. One possible solution 2.1. Overview The proposed solution attempts to minimise the risks discussed in [1.2], whilst providing a clear migration path towards full provider-based addressing within New Zealand. 2.2. Rationalisation of historical NZGATE delegations A list should be generated (and published) documenting subnets of the NZGATE blocks [3.1] which are in use at some agreed time. All blocks being so-used should be documented. 2.3. Classification of actual, existing NZGATE delegations Documented delegations [2.2] should be classified as: + large blocks (aggregatable under 19-bit prefix routes, or shorter), or + small blocks (blocks with route prefixes longer than 19 bits, but shorter than 25 bits) + tiny blocks (blocks with route prefixes longer than 24 bits) Tiny blocks (i.e. networks routed with >24 bit prefixes) are never provider independent, and should always be considered provider aggregatable. A large block may have sub-delegations to other, independently-operated networks, but only as long as there is clear consensus amongst those downstream networks that the numbers they have been delegated are provider-aggregatable, and not provider-independent. Large blocks which are operated by single operators (or which are able to be aggregated under one supernet route in the global network) should be re-documented at APNIC as entirely portable, provider-independent blocks. The choice of 19 bits as a boundary size is compatable with APNIC's policy on PI address block delegation. It is considered that the NZGATE-derived addresses of many ISPs in New Zealand will be classifiable as "large blocks", although this has not been confirmed in the field. 2.4. Administrative control of NZGATE blocks returned to APNIC All NZGATE-derived subnets not in use at the agreed time should be returned to APNIC for administration or re-delegation. No further delegations from these blocks is then advisable by any NZ provider; after the addresses are returned to the free pool they may be redelegated by APNIC elsewhere. Hence any NZ provider who makes delegations from returned blocks risks those addresses being made non-unique. 2.5. IN-ADDR.ARPA DNS delegations for NZGATE blocks Delegations for in-addr.arpa zones should be passed to a third party facilitator for management. It is not appropriate for these delegations to be handled by any single network provider. 2.6. Forced renumbering No end-user network using NZGATE subnets should be obliged to renumber as part of the normal course of their operation (but see [2.7] and [2.8]). 2.7. Process for extending address space delegations Any end-user network which requires additional addresses due to growth should be encouraged to renumber entirely using provider-aggregatable addresses. If the end-user does not wish to renumber, then additional delegations should be made from their providers' address space, according to APNIC's requirements for documentation and utilisation of existing addresses -- i.e. the customer must show good utilisation of the existing (NZGATE) addresses before additional delegations can be made. This is standard current operating procedure for provider-aggregatable delegations. 2.8. Process for managing ISP-hopping by users using "small blocks" Users of networks that are "small blocks" may change ISPs and take their numbers with them. They should be well aware of the possible jeopardy moving forward with small-prefix routes, and should be encouraged to renumber using provider-aggregatable addresses from their new provider. Any small blocks which are surrendered during a transition between providers should be returned to APNIC and not re-allocated. 3. References 3.1. Netblocks delegated historically to NZGATE-NZ The addresses concerned have all been delegated from within the NZGATE-NZ networks as recorded at APNIC, which are described as: netname: NZGATE-NZ descr: NZ Gate National Service Provider descr: Component of University Of Waikato descr: New Zeland The netblocks currently assigned to NZGATE-NZ are: inetnum: 202.27.0.0 - 202.27.255.255 inetnum: 202.49.0.0 - 202.49.255.255 inetnum: 202.50.0.0 - 202.50.255.255 inetnum: 202.36.0.0 - 202.37.255.255 inetnum: 203.96.0.0 - 203.97.255.255 The netblock 203.96.0.0 - 203.97.255.255 is perhaps erroneously attributed to NZGATE-NZ here - in fact, this block was delegated to an APNIC confederate member, NZNIC, operated by the University of Waikato. NZNIC no longer operates [3.2]. 3.2. Transition of NZGATE services to other providers The following message outlines the events surrounding the transition of international internet transit from NZGATE to other providers in early 1996, as recalled by John Houlker of Waikato University (quoted with permission). From: John Houlker To: ccc_rex@waikato.ac.nz, "'Joe Abley'" Cc: asjl@netlink.co.nz, Jamie Clark , Roger Hicks Subject: RE: [jabley@clear.co.nz: NZGATE-NZ] Date: Tue, 22 Sep 1998 16:38:45 +1200 X-Mailer: Internet Mail Service (5.5.2232.9) Joe > I would be very interested to hear your views on my original e-mail, which > is attached; in particular relating to Brett Telfer's comment, quoted in > the Herald: > > "Netgate service specialist Brett Telfer says most of the Waikato > University provided IP addresses passed to the Telecom subsidiary when > it took over the running of NZ Gate in late 1995." > > It was my understanding that NZ Gate had ceased to exist in its former > role, rather than being subsumed into Telecom? Telecom (i.e., Netway) did not "take over" NZGate, but nor did NZGate instantly "cease to exist" (such a step was simply not possible). Netway did become NZGate's supplier for a significant period while NZGate gradually reduced out of existence (I believe this started in January 1996). At the time NZGate shut down its international links this was phased with the introduction of commercial providers offering international capacity at the NZIX, but it was a complex transition with Telecom and Clear only slowly coming to grips with international IP services, and NZGate clients only slowly working out what they should do. The NZGate international circuit contracts came up to expiry in January 1996 (and we were in no position to renew for a further 12 months) and the NASA "PACCOM" access was supposed to cease in February 1996 (in the event it didn't, but we could not count on further access to the NASA FIX-WEST gateway beyond that date). We were not in a position, however, to disperse all the NZGate customers to direct supply from the newly establishing commercial suppliers (Clear made a late start with limited bandwidth, pricing was still under negotiation, all this was proving harder for the new entrants than they expected). Indeed we were asked to keep NZGate going to give our clients more time to sort out alternatives. As a result NZGate continued as a reseller, i.e., an intermediate IP provider, and we bought our international supply from Netway (our only option at the time). The University network "Kawaihiko" ceased being a customer of "NZGate" and moved to buy directly (also from Netway). As you know, somewhat later Kawaihiko took the considerably more complicated step of "multi-homing", buying from Netway and Clear in parallel (and later again, also from Telstra). In this way Netway "inherited" the NZGate address blocks as they were at that time - since they became suppliers to the remains of NZGate, and Kawaihiko (and they later picked up the then "CRINET" and AgNet as well). I would be interested in your comments, I haven't seen the Herald article, but it does sound like there are sites that don't yet know the implications of moving provider. In terms of the old blocks of former NZGate addresses it could indeed be most useful to get special treatment from the APNIC to allow greater flexibility in on-going devolution of the original NZGate group. As things stand Telecom have no option but to comply with APNIC requirements on efficient use of address space (this does not apply to the "NZNIC confederation" space that Waikato allocated to ISPs - in an attempt to assist portability - i.e., 203.96.0.0/15, which is entirely independent. Whether or not the APNIC would agree to a special approach here, it seems there may be existing customers of Telecom (or of ISPs using Telecom) who aren't yet aware of the portability issues. If not, perhaps some publicity drive out of Telecom and/or perhaps NZNOG contacts could spread the word. I asked Jim Higgens if ISOCNZ has good contacts to spread information to ISPs but I gather that (especially given the demise of ISPANZ) NZNOG may be the best shot. John 4. Contributors Joe Abley, CLEAR Communications Ltd John Houlker, Waikato University Andy Linton, NetLink Communications Ltd Many other people have contributed feedback and ideas through the NZNOG list. 5. Document History $Log: nznumber.txt,v $ Revision 1.5 1998/11/26 00:59:33 jabley Modified in response to feedback from NZNOG Revision 1.4 1998/10/08 09:23:46 jabley Some further clarification Revision 1.3 1998/10/08 09:01:42 jabley Modifications following comments from jhoulker Revision 1.2 1998/10/08 00:22:36 jabley minor typo corrected as pointed out by wellingtonian pedant Revision 1.1 1998/10/07 13:01:32 jabley Initial revision