Information Technology Reference
In-Depth Information
5.2.1.8
Auction-Based Approaches
Gupta and Somani [Gupta and Somani, 2004] proposed an auction-based
pricing mechanism for P2P file object lookup services. In their model, each
resource (e.g., a file object) is stored in a single node. However, the indices
for such a file object are replicated at multiple nodes in the network and
these nodes are called terminal nodes. When a peer initiates a lookup request
for a certain file object, the request is sent through multiple paths toward
the terminal nodes, as shown in Figure 5.6. The problem here is that the
intermediate nodes need some incentives in order to participate in the request
forwarding process.
Terminal nodes that participate in the auction
......
Client
......
Server
......
Intermediate nodes along a request path
FIGURE 5.6: The request forwarding process [Gupta and Somani, 2004].
Gupta and Somani [Gupta and Somani, 2004] suggested a novel solution to
the incentive problem. Specifically, the initiating peer attaches a price in the
request message it sends to the first layer of nodes in the request chains. Each
intermediate node on the request chains then updates the price by adding
its own “forwarding cost.” The terminal nodes also do the same updating
before sending the request messages to the data source. Upon receiving all
the request messages, the data source then performs a second price sealed
bid auction (also referred to as Vickrey auction) [Osborne, 2004] to select
the highest bid among the terminal nodes. The selected terminal node then
needs to pay the price equal to the value of the second highest bid. With
this auction-based approach, all the intermediate nodes on the request chains
have the incentive to participate in the forwarding process because they might
eventually get paid by the requester should their respective request chain wins
the auction.
For example, consider the lookup process shown in Figure 5.7. We can see
Search WWH ::
Custom Search