Japan Registry Service

An Approach for Increasing Root And TLD DNS Servers
draft-yasuhiro-dnsop-increasing-dns-server-01.txt
August 4, 2004
dnsop wg
IETF 60 Meeting
Yasuhiro Orange Morishita <yasuhiro@jprs.co.jp>
Masato Minda <minmin@jprs.co.jp>
Japan Registry Service Co., Ltd. (JPRS)

Copyright © 2004 Japan Registry Service Co., Ltd.

Japan Registry ServiceConcepts of the draft• This draft proposes increasing IP addresses
of DNS servers without IP anycast, DNS
protocol extensions• Reducing DNS packet size by using “multipleaddresses per host”– authority section of DNS response packet– This does not violate the DNS protocol• Zone administrator can add IPv6 addresses
without (or minimum) reducing of IPv4
address
Copyright © 2004 Japan Registry Service Co., Ltd.

Japan Registry Service“single-address per host”• Example: single address per hostnet.

IN
IN

NS
NS

a.gtld-servers.net.
b.gtld-servers.net.

NSIN
IN

m.gtld-servers.net.
A
192.5.6.30
A
192.33.14.30

IN

A

...
IN
a.gtld-servers.net.
b.gtld-servers.net.
...
m.gtld-servers.net.

Copyright © 2004 Japan Registry Service Co., Ltd.

192.55.83.30

Japan Registry Service“multiple-addresses per host”• Example: multiple addresses per hostnet.

INININx.gtld-servers.net.

y.gtld-servers.net.

NSNSNSINININININ
IN...

Copyright © 2004 Japan Registry Service Co., Ltd.

x.gtld-servers.net.
y.gtld-servers.net.
z.gtld-servers.net.
Aaaa.aaa.aaa.aaa
A
bbb.bbb.bbb.bbb
A
ccc.ccc.ccc.ccc
A
ddd.ddd.ddd.ddd
A
eee.eee.eee.eeeAfff.fff.fff.fff

Japan Registry Service

Changes from -00• Added 3 issues– “Number of Addresses per Server” issue– “Server Selection” issue– “Registration” issue• Added the test result on appendix A– Some various cases of combinations• Number of DNS servers• IPv4 addresses per name• IPv6 addresses per nameCopyright © 2004 Japan Registry Service Co., Ltd.

Japan Registry Service“Number of Addresses perServer” issue• DNS treats all the resource records (RRs) per‘RRSet’ basis– This makes direct influence on additional section
in a DNS packet. Because, if it is occurred at NSquery, whole of glue A records may be cancelled– This is harmful for name resolution and this must
be avoided• We did the test some various cases ofcombinations “the number of DNS servers”
and “IPv4 and IPv6 addresses per name”, theresult of the test on appendix A of the draftCopyright © 2004 Japan Registry Service Co., Ltd.

Japan Registry Service“Server Selection” Issue• If some trouble is occurred at one of the hostof ‘DNS server set’, it may be harmful forwhole of ‘server set’
– For example, one bad server may block access toother good servers• It may effect server selection algorithm ofDNS cache servers (not yet issued by draft)– On many implementations, multiple A returns‘round-robin’ basis, it may effects DNS server
selection algorithm
Copyright © 2004 Japan Registry Service Co., Ltd.

Japan Registry Service“Registration” Issue• Some registries and/or registrars(especially root = IANA), this “multiple IPaddresses registration” for DNS server host
may not be allowed– I am not sure IANA allows this or not• In this case, users can not register this• .jp registry allows the multiple IP addresses
Copyright © 2004 Japan Registry Service Co., Ltd.

Japan Registry ServiceToDo• Needs more tests and experiences– Testing the behavior of existing DNS
server implementations (especially, DNS
cache servers)• Treats of multiple address per name as glue A• Server selection algorithm• ‘Round-robin’ issue– Testing for searching most suitable patternof number of NSes, IPv4 addresses andIPv6 addresses per name
Copyright © 2004 Japan Registry Service Co., Ltd.

Japan Registry Service

Thank you• Please give us comments– Yasuhiro Orange Morishita<yasuhiro@jprs.co.jp>– Masato Minda<minmin@jprs.co.jp>

Copyright © 2004 Japan Registry Service Co., Ltd.