Originally Internet based on point-to0point communication abstraction, but many applications have emerged like multicast, anycast and host mobility that require more general abstraction and a layer of indirection that decouples the sending host from the receiving host mismatched with the original one. however, implementing these general abstraction at IP layer or application layer poses many difficulties. This paper portrays a single overlay network to serve as an indirection infrastructure i3 that combine the generality of IP layer solutions with the deployability of overlay solutions. It offers best effort service without reliability or ordered delivery.
i3 serves as a rendezvous-based communication abstraction where a single node in this network is responsible to store packets sent to all identifiers id's that agree in the first k bits. Receiver sends trigger (idt, addr) to indicate that all packets with longest prefix match id should be forwarded by the i3 infrastructure to the node identified by addr. i3 achieves general communication abstraction of
i) mobility by maintaining end-to-end connectivity even when both end points move simultaneously by simply updating the receiver's trigger to consider the new address
ii) multicast by simply having hosts maintain triggers with the same identifier
iii) Anycast by simply having hosts of anycast group maintain triggers which are identical in a prefix of length k bits. This also is helpful to encode application preferences through the use of m-k bits which can used to balance the load over the servers
Another generalization of i3 is to replace an identifier by identifier stack that can be a list of identifier or address such that a source can send a packet to a series of identifier. These type of generalization is helpful to transform the data by third part server or to pass the data through firewall before its delivering to the destination, to enabling heterogeneous receivers to subscribe to same multicast group.
i3 is implemented depending on Chord lookup protocol using circular identifier space with m=256bits and k=128 bits, such overlay
network is self configuring in that a node can join i3 infrastructure simply. i3 uses soft state approach to be robust against node failures depending on the packet routing, end-host's periodic refreshing to maintain their triggers and stack identifier. However, the routing in i3 overlay network is less efficient than routing via IP. Thus, the clients caches the i3 server's IP address and the receiver has to choose their triggers with an identifier that is located on nearby server.
i3 serves as a rendezvous-based communication abstraction where a single node in this network is responsible to store packets sent to all identifiers id's that agree in the first k bits. Receiver sends trigger (idt, addr) to indicate that all packets with longest prefix match id should be forwarded by the i3 infrastructure to the node identified by addr. i3 achieves general communication abstraction of
i) mobility by maintaining end-to-end connectivity even when both end points move simultaneously by simply updating the receiver's trigger to consider the new address
ii) multicast by simply having hosts maintain triggers with the same identifier
iii) Anycast by simply having hosts of anycast group maintain triggers which are identical in a prefix of length k bits. This also is helpful to encode application preferences through the use of m-k bits which can used to balance the load over the servers
Another generalization of i3 is to replace an identifier by identifier stack that can be a list of identifier or address such that a source can send a packet to a series of identifier. These type of generalization is helpful to transform the data by third part server or to pass the data through firewall before its delivering to the destination, to enabling heterogeneous receivers to subscribe to same multicast group.
i3 is implemented depending on Chord lookup protocol using circular identifier space with m=256bits and k=128 bits, such overlay
network is self configuring in that a node can join i3 infrastructure simply. i3 uses soft state approach to be robust against node failures depending on the packet routing, end-host's periodic refreshing to maintain their triggers and stack identifier. However, the routing in i3 overlay network is less efficient than routing via IP. Thus, the clients caches the i3 server's IP address and the receiver has to choose their triggers with an identifier that is located on nearby server.The paper simulates i3's efficiency with randomly distributed identifier. The big challenge was to achieve efficient routing since the end-host doesn't have good control over the location of it's triggers. A ratio of inter node latency on i3 network to that on IP network is used to enhance the performance of i3.
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