Content Routing Protocol Design Karthikeyan Ganesan Shruti Venkatesh Rafay Zamir

Assumptions and Address Scheme Assumptions End hosts can only connect to routers Same content might be available at multiple end nodes or might not be available at any node.

Bootstrapping and Discovery Algorithm End hosts entering a network broadcast content list.(contains host address and list of contents) End hosts broadcast content change.(contains host address and list of changed contents and their status) Built over IP based routing. Packet Header The content request packet header contains the source address, Content ID and Sequence Number(n th packet in content ).

Baseline Algorithm Content routing algorithm Address based Forwarding table Content Table Request contains source address, content ID and Sequence Number. Router forwards towards closest source with content End to End delivery from Content provider to requester.

Data Transfer and Reliability Message Forward Unicast Content Packet forward Flooding ARQ Scheme End-to-end Selective-repeat

Advantages and Disadvantages Content table becomes too large with increasing number of hosts or content. (Alternative – Storing only the address of the closest Provider for each Content) SR has lower latency than other schemes. Upon Deletion of Content, a transfer packet can be sent to its closest router. This reduces the time taken for the user to receive content from a new host.

Example Scenarios

Scenario get (content_C3) H1 H2 H3 C1 C2 C3 R1R2R3R4 R5 H2 sends request to R5. R5’s content table indicates H3 has the content and uses the forwarding table to forward content to R2 R2’s content table indicates H3 has the content and uses the forwarding table to forward content to R3 The same continues till H3. H3 then uses the source address of the request packet to transmit the content.

H1 H2 H3 C1 C2 C3 R1R2R3R4 R5 Scenario get (content_C2) H2 sends request to R1. R1’s content table indicates H3 and H2 have the content and uses the forwarding table to see H2 is closer and forwards to R2 R2’s content table indicates H3 and H2 have the content and uses the forwarding table to forward content to R5 The same continues till H2. H2 then uses the source address of the request packet to transmit the content.

H1 C3 Scenario get (content_C1) H2H3 H4 C1 C2 C1 R1 R2 R3 R4 R5 This scenario is similar to scenario 2. The request is sent from H1->R1->R2->R3->R4->R5->H2

Thank you