in-addr.arpa and the uninet project address space
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IN-ADDR.ARPA and the
UNINET Project address space
Presentation to ISOC-ZA WorkshopFriday 13 September 2002
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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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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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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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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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IPv4 Addresses (e.g. 196.79.225.4 or11000100 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/) IPv6 – it’s there, but far from being accepted
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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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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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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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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.za A 196.21.79.50
(forward lookup) Who sent this packet with source address 196.21.79.50 ?
50.79.21.196.in-addr.arpa PTR disa.tenet.ac.za (reverse or inverse lookup)
Every A record should have a matching PTR record
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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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Simple illustration - delegation to 21.196.IAA In 196.in-addr.arpa (administered by ARIN)
Delegation record (non-authoritative):21 NS disa.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
1 01 NS ns1.wits.ac.zasnow.spg.net
PTR records for specific addresses: e.g. 196.21.79.5050.79 PTR disa.tenet.ac.za
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More interesting illustrationScenario: 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”zone1 NS ns1.uniblik.ac.za
hippo.ru.ac.za Definition of aliases:
1 CNAME 1.zone1.79.21.106.in-addr.arpa2 CNAME 2.zone1.79.21.106.in-addr.arpa… … …63 CNAME 63.zone1.79.21.106.in-addr.arpa
In zone1.79.21.196.in-addr.arpa (admin by UniBlik)1 PTR ns1.uniblik.ac.za2 PTR mail.uniblik.ac.za… … …63 PTR lib.uniblik.ac.za
See RFC 2317, Classless IN-ADDR.ARPA delegation, 1998.
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Project CURLA
CleanUpReverseLookups andARIN Whois
(for UNINET Project address space)
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UNINET Project address space
192.96 196.13
196.6 196.21
196.10 196.24
196.11 198.54
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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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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Origin ASs
2018 TENET
2686 IBM
2830 UUNET
2905 UUNET
3741 The Internet Solution
5713 Telkom SA Limited
5734 Telkom SA Limited
6083 Olivetti Africa
6089 Intertech Systems
7460 LIA Internet Access
8668 PTC Zimbabwe
12258 Vodacom Internet Co
16416 Mycomax
16637 Johnnic e-Ventures
17148 First National Bank
23058 Discovery Health
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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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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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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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Thanks for listening!
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