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1 IN-ADDR.ARPA and the UNINET Project address space Presentation to ISOC-ZA Workshop Friday 13 September 2002
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2 Topics… IN-ADDR.ARPA (IAA) Domain names IP address allocation: before and after CIDR IAA - just part of the DNS Classless delegation of IAA domains The UNINET Project address space The blocks and the history What I’m trying to do – Project CURLA Objectives and policies And then?
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3 Domain names (e.g. python.cs.wits.ac.za) Hierarchical structure Root of hierarchy now ruled by ICANN Administration delegated hierarchically along political, organizational and legal persona lines
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4 Domain names (e.g. python.cs.wits.ac.za) No inherent limit to number of different names, but… Is a name just an easily-remembered form of address, or A brand, endowed with intellectual property rights?
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5 Domain names (e.g. python.cs.wits.ac.za) No inherent limit to number of different names, but… Is a name just an easily-remembered form of address, or A brand, endowed with intellectual property rights? Battle for control of ICANN and naming policy has been won by the intellectual property lobby (see:“Ruling the root”, Milton L Mueller, The MIT Press, 2002)
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6 IPv4 Addresses (e.g. 196.79.225.4 or 11000100 01001111 11100001 00000100 ) IP packets carry address info – not name info Routing strategies based solely on addresses Fixed number (4 294 967 296) of addresses Allocations policy controlled by ICANN’s Address Supporting Organization Allocations operations contracted out to regional registries (ARIN, RIPE, APNIC,…some day, also AfriNIC) WHOIS databases (e.g. www.arin.net/whois/)www.arin.net/whois/ IPv6 – it’s there, but far from being accepted
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7 In the early days…. The (then) Internic Allocated class A, B and large C itself delegated small class C allocations/assignments to regional/national bodies Assigned class C space in chunks of 256 addresses Assignments unrelated to routing responsibilities The “UNINET Project” address space in SA Eight “/16-sized” blocks of class C space Assignments made to around 300 organizations TENET is the ARIN Maintainer Problems began to emerge Growth of the size of Internet routing tables Wastage and exhaustion of the address space
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8 Classless Inter-Domain Routing (CIDR) Allows network prefixes of any length Permits assignment of 8, 16, 32,…. addresses Decentralizes the allocation process to ISPs: ISPs aggregate prefixes and routes Does not apply to earlier assignments …like UNINET project space Regarded by assignees and ISPs as “portable” space The “swamp” – globally routed /24s
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9 Classless Inter-Domain Routing (CIDR) Decentralizes the allocation process to ISPs: Registries make no new allocations or assignments smaller than /19 New allocations only to meet demonstrated needs Top tier ISPs get larger allocations, then make sub- allocations to lower-tier ISPs ISPs make assignments to their customers Customers return these assignments upon changing ISPs
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10 Domain Name Service (DNS) Database that defines the operational correspondences between domain names and IP addresses To send a packet to disa.tenet.ac.za, what destination address must be used? disa.tenet.ac.zaA196.21.79.50 (forward lookup) Who sent this packet with source address 196.21.79.50 ? 50.79.21.196.in-addr.arpaPTRdisa.tenet.ac.za (reverse or inverse lookup) Every A record should have a matching PTR record
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11 IN-ADDR.ARPA Structures reverse lookup records into DNS zones, to enable: efficient reverse lookups: d.c.b.a.in-addr.arpa name? maintenance by appropriate parties Root zone: “in-addr.arpa” Administered by ARIN arrowroot.arin.net, buchu.arin.net, chia.arin.net,… Standard DNS rules apply to IAA sub-zones: SOA records Defining, naming and delegating to sub-zones Using aliases and canonical names Deploying primary and secondary name servers
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12 Simple illustration - delegation to 21.196.IAA In 196.in-addr.arpa (administered by ARIN) Delegation record (non-authoritative): 21NSdisa.tenet.ac.za rain.psg.com In 21.196.in-addr.arpa SOA record Authoritative NS records (matching parent’s delegations) Delegations to child domains: e.g. 101.21.196.in-addr.arpa 101NSns1.wits.ac.za snow.spg.net PTR records for specific addresses: e.g. 196.21.79.50 50.79PTRdisa.tenet.ac.za
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13 More interesting illustration Scenario: The prefix 196.21.79.0/26 is assigned to UniBlik. In 79.21.196.in-addr.arpa (admin by TENET) Delegation to zone called “zone1.79.21.196.in-addr.arpa” zone1NSns1.uniblik.ac.za hippo.ru.ac.za Definition of aliases: 1CNAME 1.zone1.79.21.106.in-addr.arpa 2CNAME 2.zone1.79.21.106.in-addr.arpa …… … 63CNAME 63.zone1.79.21.106.in-addr.arpa In zone1.79.21.196.in-addr.arpa (admin by UniBlik) 1PTRns1.uniblik.ac.za 2PTRmail.uniblik.ac.za ……… 63PTRlib.uniblik.ac.za See RFC 2317, Classless IN-ADDR.ARPA delegation, 1998.
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14 Project CURLA Clean Up Reverse Lookups and ARIN Whois (for UNINET Project address space)
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15 UNINET Project address space 192.96196.13 196.6196.21 196.10196.24 196.11198.54 Two yellow blocks: All assignees have Telkom as common ISP under HEIST agreement prefixes aggregate OK! TENET’s AS 2018 is origin AS for both as /16 prefixes.
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16 Clean up strategy - 1 There are 1 536 class C networks For each, determine: prefix and origin AS, if any (from BGP tables) Current ARIN Whois assignee and POC, if any Group according to contiguity, origin AS and assignee
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17 Origin ASs 2018TENET 2686IBM 2830UUNET 2905UUNET 3741The Internet Solution 5713Telkom SA Limited 5734Telkom SA Limited 6083Olivetti Africa 6089Intertech Systems 7460LIA Internet Access 8668PTC Zimbabwe 12258Vodacom Internet Co 16416Mycomax 16637Johnnic e-Ventures 17148First National Bank 23058Discovery Health
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18 Clean up strategy - 2 For prefixes that are being routed: Ask origin ISP for customer identity and contact info Then, if Customer <> Whois assignee, ask customer to justify his use of the space For prefixes that are NOT being routed Ask Whois assignee why space should not be returned Decide on Whois and IAA updates
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19 Policies If current user = Whois assignee OR credibly claims to inherit Whois assignee’s rights, THEN In Whois, re-assign block to current user Inform ISP Else Consult ISP with view to new assignment from ISP instruct user to stop using addresses by end of 2002. Delete assignment from Whois No new assignments to end-users
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20 When Project CURLA is over? What to do with unassigned address space? Return all six blocks to ARIN? Wait for AfriNIC to commence operations? Sit on the space? Never assign or allocate blocks < /19 IDEA: Allocate or assign /19 or larger prefixes In consultation with AfriNIC To ISPs or other entities that apply for it For use by schools, public libraries or other public benefit organisations ISPs should refuse to route portable prefixes for customers when customer <> ARIN assignee (possible ISPA / AfriNIC policy?)
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21 Thanks for listening!
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