Randomized Greedy Hot-Potato Routing on the Multi-Dimensional Torus

We present extensive simulation and analysis on a traditional, simple, efficient dynamic hot potato routing algorithm on a multi-dimensional torus network. These simulations are performed under a more recent network model than previous, more limited studies, with dynamic (rather than batch) models, no flow-control, and extended high dimensional scenarios. We collect more comprehensive statistics on system performance, and empirically show that the system can recover from worst-case scenarios to quickly re-achieve its standard steady-state delivery rates, with expected delivery time for a packet of O(n), where n is the initial packet distance from its destination. Experiments also show that for our model, the constant multiplier hidden in the O() notation decreases with higher dimensions

Internet Content Delivery as a Two-sided Market

Sisällön määrä kasvaa Internetissä ja nykyisen Internetin kyky skaalautua Internetin kapasiteetin kasvavaan kysyntään on epäselvä. Tämän selvittääkseen lukuisia tutkimuksia tulevaisuuden Internetistä on käynnistetty, mukaan lukien tietopohjainen verkko (information networking). Tämä työ hyödyntää arvoverkkoja ja kaksipuolisten markkinoiden teoriaa selittämään nykyiset ja ennustamaan tulevaisuuden markkinarakenteet Internet sisällönjakelussa. Rakennettuja arvoverkkoja ja SWOT analyysia käytetään eri sisällönjakelumallien vertailemiseen; asiakas-palvelin-, CDN- ja CCN-malli. Lisäksi, tietopohjaisen verkon (CCN) markkinapotentiaalia tutkitaan. Neljä kaksipuolista markkinaa on tunnistettu Internetin yhteyskerroksella tässä työssä ja kaksipuolinen analyysi ennustaa CDN:n ja palvelutarjoajien kasvamista. Toisaalta sisällöntarjoajien määrää odotetaan laskevan kaksipuolisen markkinan analyysin perusteella. Arvoverkkoanalyysi osoittaa, että CDN ja CCN mallit vähentävät pääsyverkon tarjoajien liikennettä muiden tarjoajien verkkoihin (off-net liikenne). Jos pääsyverkon tarjoajien off-net liikenne vähenee huomattavasti, CCN mallilla voi olla markkina-arvoa. Sisällönjakelumalleille laadittujen arviointikriteerien perusteella tehty SWOT analyysivertailu osoittaa, että useimmat sidosryhmät arvostavat CDN ja CCN malleja kun taas sisällöntarjoaja selvästi suosii CCN mallia. Tulokset ovat arvokkaita, koska ne tunnistavat tarpeen tehdä lisätutkimusta tietopohjaisen verkon liiketoimintamalleista ja toteutettavuudesta.The amount of content is increasing in the Internet but the current Internet's ability to scale with the growing demand for Internet capacity is unclear. To determine this, various studies on the future of the Internet have been initiated; including studies on information networking. This work utilises value networks and the two-sided market theory in explaining the current and predicting the future market structure of Internet content delivery. The formulated value networks and SWOT analysis are used for comparing the different content delivery models; the client-server model, Content Delivery Networks (CDNs) and the Content Centric Network (CCN) model. In addition, the market potential for information networking (CCN) is investigated. Four two-sided markets in the Internet interconnection layer are identified in this work and the two-sided analysis predicts the consolidation of CDNs and Internet service providers (ISPs). However, the number of content providers is expected to rise based on the two-sided market analysis. The value network analysis shows that the CDN and CCN models reduce off-net traffic compared to the client-server model for Internet access providers (IAPs). If the off-net cost for IAPs is reduced significantly, the CCN model may have a business case. The SWOT analysis comparison based on the formulated evaluation criteria for content distribution models concludes that most stakeholders prefer CDN and CCN models, whereas the content provider clearly favours CCN. The results are valuable in recognising the need for further research on the information networking's business model and the feasibility of implementation

Potential Function Analysis of Greedy Hot-Potato Routing

We study the problem of packet routing in synchronous networks. We put forward a notion of greedy hot-potato routing algorithms and devise techniques for analyzing such algorithms. A greedy hot-potato routing algorithm is one where ffl The processors have no buffer space for storing delayed packets. Therefore, each packet must leave any intermediate processor at the step following its arrival. ffl Packets always advance towards their destination if they can. Namely, a packet must leave its current intermediate node via a link which takes it closer to its destination, unless all these links are taken by other packets. Moreover, in this case all these other packets must advance towards their destinations. We use potential function analysis to obtain an upper bound of O(n p k) on the running time of a wide class of algorithms in the 2-dimensional n \Theta n mesh, for routing problems with total of k packets. The same techniques can be generalized to obtain an upper bound of O(exp(d)..

Potential Function Analysis of Greedy Hot-Potato Routing (Extended Abstract)

Amir Ben-Dor Shai Halevi y Assaf Schuster z January 21, 1994 Abstract In this work we study the problem of packet routing in synchronous networks of processors, in which at most one packet can traverse any communication link in each time step. We consider a class of algorithms known as hot-potato or deflection routing algorithms. The important characteristic of these algorithms is that they use no buffer space for storing delayed packets. Each packet, unless already arrived to its destination, must leave the processor at the step following its arrival. The main advantage in hot-potato routing is that there is no need to store delayed packets in the processors, and therefore, the processors can be much simpler, and contain less hardware. This work is concerned with greedy routing, in which a packet is bound to use an out-going link in the direction of its destination, whenever such a link is available. In this way, greediness guarantees that, unless some global congestion forbids..