475 |
However, in all above schemes each hop in the overlay shortens the distance between |
However, in all above schemes each hop in the overlay shortens the distance between |
476 |
current peer working with the data lookup and the key which was looked up in the identifier space. |
current peer working with the data lookup and the key which was looked up in the identifier space. |
477 |
|
|
478 |
Skip Graphs \cite{AspnesS2003} and SWAN \cite{bonsma02swan} employ a key space very similar to a tightly structured |
Skip Graphs \cite{AspnesS2003} and SWAN \cite{bonsma02swan} employ a identifier space |
479 |
overlay, but in which queries are routed to \emph{keys}. In these systems |
in which queries are routed to \emph{keys}. In these systems |
480 |
a peer occupies several positions in the identifier space, one for each |
a peer occupies several positions in the identifier space, one for each |
481 |
application-specific key. The indirection of placing close keys in the |
application-specific key. The indirection of placing close keys in the |
482 |
custody of a provider peer is removed at the cost of each peer maintaining one |
custody of a provider peer is removed at the cost of each peer maintaining one |
484 |
which has initially published services into the overlay. |
which has initially published services into the overlay. |
485 |
|
|
486 |
PeerNet \cite{eriksson03peernet} differs from other tightly structured overlays in that it operates |
PeerNet \cite{eriksson03peernet} differs from other tightly structured overlays in that it operates |
487 |
at the \emph{network} layer. PeerNet makes an explicit distinction |
at the \emph{network} layer instead of application layer. This property would provide a common interface |
488 |
|
to all Peer-to-Peer systems using PeerNet. PeerNet makes an explicit distinction |
489 |
between peer identity and address, which is not supported by standard |
between peer identity and address, which is not supported by standard |
490 |
TCP/IP-protocols. Otherwise, PeerNet has the same performance properties |
TCP/IP-protocols. PeerNet has the same performance properties as other tightly structured |
491 |
as other tightly structured overlays, i.e., $O(\log{n})$ space required |
overlays, i.e., $O(\log{n})$ space required for maintaining information about other peers in |
492 |
for maintaining information about other peers in the system and |
the system and $O(\log{n})$ data lookup efficiency. |
|
$O(\log{n})$ data lookup efficiency. |
|
493 |
|
|
494 |
|
|
495 |
\section{Summary} |
\section{Summary} |