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Translation Spot Negotiation in IPv4/IPv6-Coexist Mesh. draft-cui-softwire-pet-03 Yong Cui, Mingwei Xu , Peng Wu Jianping Wu, Xing Li, Chris Metz. Challenges of translation. Basic IPv4-IPv6 transition techniques Tunnel for IPv4-over-IPv6/IPv6-over-IPv4 traversing
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Translation Spot Negotiation in IPv4/IPv6-Coexist Mesh draft-cui-softwire-pet-03 Yong Cui, MingweiXu, Peng Wu Jianping Wu, Xing Li, Chris Metz
Challenges of translation • Basic IPv4-IPv6 transition techniques • Tunnel for IPv4-over-IPv6/IPv6-over-IPv4 traversing • Translation for IPv4-IPv6 inter-connection • But translation has technical challenges • Scalability: IPv4 addr consuming/mapping maintenance • Application layer translation • Operation complexity: per-packet/from IP to app layer • Lack of efficient NAT46 mechanism • Refer to RFC4966 for more details • Inherent properties due to the principle of translation
Tunnel for translation spot “transfer” • Naturally, translation happens on IP border • Use a tunnel to transfer the translation to other spot • Tunnel for traversing between translation spot and IP border • Choose translation spot flexibly • Translator with better hardware capability; traffic less-aggregated; support ALG or not; etc. IP Border Translation Spot IPvX Backbone IPvY Internet IPvXEdge AFBR Xlate BR IP Border Translation Spot IPvX Backbone IPvY Internet IPvXEdge Xlate TE AFBR Xlate AFBR TE BR IPvY-over-IPvX Tunnel
Real Problem in IPv4/IPv6-coexist mesh • Mesh Scenario • Exists in CERNET2 • Communications • E-IP over I-IP traversing(RFC5565) • Inter-connection between E-IP & I-IP (the scope of this draft) • Translation spot • AFBR (IP-border) • BR (non IP-border) I-IP Internet E-IP Internet BR AFBR I-IP Client Net I-IP Backbone E-IP Client Net BR AFBR I-IP Client Net E-IP Client Net I-IP Client Net E-IP Client Net
Solution • Softwire tunnel(RFC 5565) to transfer translation spot • E-IP over I-IP routing(RFC 5549) required for translation • Translation spot negotiation using BGP on AFBRs/BRs • BGP already supported by AFBR/BR in mesh scenario • Protocol extensions: A new BGP Attribute "Translation Information Attribute" with 4 TLVs, to • Decide translation spot • Deliver translation context