28 | | a. Source-Routed Forwarding:[BR] Unlike existing IP source routing protocols, this !ChoiceNet forwarding service will only forward a packet if the packet contains proof that the sender ''paid'' for the forwarding service at each hop along the source-route. Each entry in the source-route not only identifies the next hop, but also provides a ''proof of purchase'' indicating that the sender paid for use of the next hop. This proof-of-purchase is checked at the next hop before the packet is allowed to proceed forward. Packets without proof are automatically dropped.[BR] [BR] Senders in this model contact a ''Path Service (PS)'' that discovers multiple paths between any two nodes. The send application tells the PS what type of path is desired -- for example a High Bandwidth (and presumably expensive) path, or a Low Bandwidth path (that may be substantially cheaper).The sender also includes some form of payment in the request to the PS, who in turn formulates the best path for the sender, and then returns the best path along with the ''proof of purchase'' needed to get packets through |
29 | | each hop along the path. Senders then include the path and proof of purchases for each router along the path in the packet header which is examined by every router along the path.[BR] [BR] To implement this service, we install a '''Click Router''' in the linux kernel along with a click module that implements |
| 28 | a. Source-Routed Forwarding:[BR] Unlike existing IP source routing protocols, this !ChoiceNet forwarding service will only forward a packet if the packet contains proof that the sender ''paid'' for the forwarding service at each hop along the source-route. Each entry in the source-route not only identifies the next hop, but also provides a ''proof of purchase'' indicating that the sender paid for use of the next hop. This proof-of-purchase is checked at the next hop before the packet is allowed to proceed forward. Packets without proof are automatically dropped.[[BR]] [[BR]] Senders in this model contact a ''Path Service (PS)'' that discovers multiple paths between any two nodes. The send application tells the PS what type of path is desired -- for example a High Bandwidth (and presumably expensive) path, or a Low Bandwidth path (that may be substantially cheaper).The sender also includes some form of payment in the request to the PS, who in turn formulates the best path for the sender, and then returns the best path along with the ''proof of purchase'' needed to get packets through each hop along the path. Senders then include the path and proof of purchases for each router along the path in the packet header which is examined by every router along the path.[[BR]] [[BR]] To implement this service, we install a '''Click Router''' in the linux kernel along with a click module that implements |