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To locate a page, one sends the reference to a Logiweb server using the Logiweb protocol. This is typically done by sending a get request as a udp packet to the server.
The server has four possible responses: (1) The server knows the url of the page and sends this url. (2) The server thinks that the page does not exist anywhere in the world and says so. (3) The server refers to another server by sending the url of the other server. (4) The server sends a short notice saying that it is too busy to reply at the present time.
The last of the four options is a safety valve included in the Logiweb protocol to handle denial of service attacks. We ignore the existence of this safety valve in the following and explain what happens if the safety valve remains unused.
When locating a page, option (3) above may occur several times: one may have to consult a chain of servers before ending in situation (1) or (2).
As mentioned, a reference is a sequence of bytes. At any time while locating a page, some of the bits of the reference are 'resolved' and some are 'unresolved'. To begin with, all bits are unresolved and, for each time situation (3) above occurs, the number of resolved bits increases. Hence, locating a page terminates after consulting at most as many servers as there are bits in the reference.
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