IPv6 in the Greek School Network Michalis Oikonomakos - Network Engineer, Greek School Network & CTIP Athanasios Douitsis - Network Engineer Greek School Network & NTUA NOC / ICCS
Brief overview of Greek School Network (GSN) GSN is the Educational Network of Ministry of Education Schools (16.200) and (900) administrative units are broadband connected Serves 180.000 teachers and 1.350.000 pupils Hosts 12.747 websites and 19.223 blogs (Personalized access to 84.944 teachers and 65.294 pupils) Develops, provides and supports value added services, for education and administration of education. Helpdesk supports >30.000 tickets/year and a multiple number of phone calls Cofounded by European Union and Greek state Designed, implemented and operated by the Ministry of Education and 12 Research Centers, Universities and Technological Educational Institutes
GSN s Electronic Services Broadband access Email & emailing lists Web portals, which are provide useful educational material Web filters, to protect pupils from inappropriate web content Special portal for internet safety Web hosting and wizards to create dynamic web pages Blogging and social networking E-Learning and e-portfolios Special portal for Educational Open Source Software Video on Demand and Live web-castings Web conferences Schools magazines
Network status 56 PoPs (at least 1 pop in every prefecture), interconnected using GRNET s and SYZEYXIS backbone 10Gbps internet connection via GRNET, which serves as upstream provider to GSN 2 geographically separated Datacenters (soon to be 3) Various access methods (MetroEthernet, xdsl, Wireless, Optical Fiber, Leased Lines)
IPv6 history and status @ GSN Early involvement in IPv6 Case study in book Global IPv6 Strategies: From Business Analysis to Operational Planning (10 years ago) Address space used to be a /47 & a /48 Nowadays is a /48 (backbone) and a /40 for school and administrative units Dual stack implementation OSPFv3 as IGP / BGPv4 Basic services running ipv6 (www, DNS etc) >6Gbps daily IPv4 internet traffic >350Mbps daily IPv6 internet traffic
SCH ACCESS NETWORK IPV6 ADDRESS MANAGEMENT SYSTEM
SCH Previous IPv6 Setup In place for almost 10 years Same prefix pool for all units /63 per unit /64 for WAN/PPP, /64 for DHCPv6 PD Manual assignment of prefixes Maintenance by SCH operators Error-prone, cumbersome Vendor specific IPv6 RADIUS attributes stored verbatim in directory as radiusreplyitem(s)
SCH Future IPv6 Requirements Design for another 10 years ahead Static /56 per school 256 VLANs plus a static /64 for the PPP/WAN link Automated Prefix assignment/maintenance Storage of clean IPv6 prefixes in LDAP (Vendor neutral) Extension of LDAP schema with dedicated IPv6 attributes RADIUS translates to VSAs only if necessary Grouping of unit prefixes according to category e.g. high school, administrative, elementary Easier policy enforcement, access lists, content filtering very important for elementary category
Prefix Calculation from Offset Delegated Pool space: 2001:648:2000:0000::/ 40 + Stored offset 431d (16 bits) = Final Delegated Prefix 2001:648:2043:1d00::/5 6 Storage of address offset instead of full prefix Storage in ordinary DB Easier sorting, easier counting Renumbering possible without alteration of thousands of user records Simple change of pool spaces
IPv6 Pool Dimensioning Assumption of double space requirements in next 10 years Separate prefix group per unit category 2001:648:3400::/44 core network / datacenter 2001:648:3410::/44 administrative 4000 2001:648:3420::/43 high school units 8000 2001:648:3400::/4 0 2001:648:3440::/42 elementary units 16000 2001:648:3480::/41
RADIUS and LDAP modifications Directory service (LDAP) 2 new attributes FramedIPv6Prefix DelegatedIPv6Prefix RADIUS Framed-IPv6-Prefix (from LDAP attribute) Delegated-IPv6-Prefix (from LDAP attribute) Framed-Interface-ID (TBD: unset, static or random) DNS-Server-IPv6-Address (TBD: static, dynamic) Building an IPv6 Address Management System 11
Software goals Automated operation Batch mode Assign prefix to every unit in LDAP Single unit mode Assign prefix to specific unit supplied as argument Ability for on the fly renumbering In case of IPv6 pools space reconfiguration Lifecycle automation (auto detection of creation and deletion of units)
Software requirements Update directory entries Multiple configurable groups/pools Different delegated prefix length per group Assignment of framed, delegated prefixes per unit Existing unit Retain same prefix New unit Assignment of free prefix Deleted unit Recycle prefix Deletion / prefix reassignment logging (for audit/accounting purposes)
System Operation Overview Calculate prefixes from offset Store prefixes Address assignment software SCH Master Directory Classify unit, get pool for category, get offset for unit Pool and address offset DB Read unit If new unit, create a new offset in DB or recycle oldest unused
Software code Standalone software Perl >= 5.14 Communication with DB & LDAP Approx. 35 CPAN module dependencies MySQL 5.x https://github.com/aduitsis/ipv6-static/tree/sch
Thank you! Any Questions? For the IPv6 Address management system, see also: http://www.slideshare.net/aduitsis/building-an-i-pv6- address-management-system-47192345