1. Aayush Patidar Ashwin Ramakrishnan Manoj Juneja
ECE 544 Project3
Aayush Patidar
Ashwin Ramakrishnan Manoj Juneja

2. Assumptions and Address Scheme
End hosts can only connect to routers.
Same content is available at multiple end nodes.
Routers are statistically configured.
Hosts store content on receiving other contents.
Cost of the link between adjacent routers is 1.
Naming scheme and eventual address scheme
Router -> 0-254
End hosts ->0-255
Content ID-> 0-255

3. Baseline Algorithm Content routing algorithm
Contents are advertised by hosts through their routers which in turn advertise to neighboring routers. (Similar to RIP)
Content Request
To route a content request packet, the content id of the packet is seen and the next hop is looked up on the forwarding table.
Best amongst the multiple hosts are decided by hop count
The content once found is delivered in a packet which contains the content and the reverse of the list of traversal.

4. Baseline Algorithm Contd.
Content Not Found
At some point in network, Request for content Ci reaches a router that hosted it previously(just deleted) will send a Content Not Found Packet in the reverse direction and every node in the reverse path will update it’s CRT and look for alternative path and sends request over it.

5. Packet Format Update Packet Content Request Packet Type CID Length
Hop Count
Type
CID
Len
Router ID (Stack)

6. Packet Format Data Packet Content Not Found Packet Type CID Len
Router ID (Stack)
Data
Type
CID
Len
Router ID (Stack)

7. Content Routing Table CID Next Hop TTL Hop Count C1 R1 20 1 C2 R5 3022 2 C3 25 H1 H2 H3 C1 C2 C3 R1 R2 R3 R4 R5

8. Data Transfer and Reliability
Message Forward
Message forwarding used is Unicast.
Types of Packets :
Update Packet
Content Request Packet
Acknowledgement Packet
Content Not Found Packet
Data Packet
ARQ Scheme
The ARQ scheme used is Hop by Hop and Stop and wait protocol is used.

9. Advantages and Disadvantages
Reliable due to Stop-and-wait protocol and the Content Not Found packet
Exhaustive search due to Content Not Found packet
NO IP : content based rounding
Simple Architecture
Stateless routers
Minimal Network Utilization
Disadvantages :
Slower than broadcasting every data request

10. Example Scenario @host_H1: get (content_C2) H1 H2 H3 C1 C2 C3 R1 R2 R3

11. Appendix: Network Architecture
Refer to the following example scenarios for analysis purposes:
Scenario get (content_C3) H2 C1 C2 R5 C3 H1 R1 R2 R3 R4 H3

12. Appendix: Network Architecture
Scenario get (content_C2) H1 H2 H3 C1 C2 C3 R1 R2 R3 R4 R5

13. Appendix: Network Architecture
Scenario get (content_C1) H1 H2 H3 H4 C1 C1 C2 C3 C1