2002 - cesnet

5.3 Basic IPv6 ServicesIn addition to the stateless autoconfiguration mentioned above, the followingtwo services are necessary for an effective operation of IPv6: DNS and, less importantly,DHCP. These three pillars of clients’ automatic configuration shouldmake sure that end users do not even know whether they are using IPv4 or IPv6for their access to certain services.However, this ideal situation is not within easy reach. This is because not all applicationssupport IPv6 and it is necessary to complete a lot of tasks concerningthe standards and implementations of DNS and DHCP services.5.3.1 DNSThe DNS service for IPv6 within CESNET2 was significantly reorganised in 2002.The primary name server of the cesnet.cz domain and reverse domains wasretained in the Prague node and the secondary IPv6 name server was movedto Ostrava. With respect to the current schism concerning reverse domains, wehave all records doubled in both trees, i.e., under ip6.arpa and ip6.int.In every node of the IPv6 network, there was a separate name server establishedfor IPv6 or records for IPv6 were added to existing name servers of localdomains. The relevant reverse domains were also delegated to these nameservers.A majority of the name servers mentioned above run the BIND daemon, version9; however, we are testing other alternatives, too, e.g., DJBDNS 7 . With respectto the frequent errors in the BIND program, its monoculture represents asecurity risk that should be neutralized in the future by additional implementationsof DNS servers.5.3.2 DHCPv6The protocol of the clients’ autoconfiguration, DHCPv6, has not been standardizedin the form of RFC in IETF. Testing carried out within the 6NET projects hasalso shown that none of the available implementations of DHCPv6 are reallyapplicable, as they usually lag behind even the draft standard, realize only partof the protocol or include substantial errors. This is why we decided not to implementthis protocol, which, fortunately, means no serious limitations with theexisting number of end users of IPv6.7http://www.djbdns.org/70 High-speed National Research Network and its New Applications 2002