Difference between revisions of "The Wunet Protocol"

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But Wunet only supports only a rudimentary form of multicast and there is no provision for error control (e.g., dropped bits).
 
But Wunet only supports only a rudimentary form of multicast and there is no provision for error control (e.g., dropped bits).
 
It was developed primarily for educational purposes during the Fall 2009 semester for a course in the Computer Science and Engineering Department at Washington University in St. Louis.
 
It was developed primarily for educational purposes during the Fall 2009 semester for a course in the Computer Science and Engineering Department at Washington University in St. Louis.
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= A Wunet Example =
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= Wunet Concepts =
 
= Wunet Concepts =
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== ST (Stats Table) ==
 
== ST (Stats Table) ==
  
= Examples =
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= More Wunet Examples =
  
 
= ONL Implementation =
 
= ONL Implementation =

Revision as of 03:34, 26 January 2010

Template:Newpage

History of Wunet

The Wunet protocol is a paired-down version of the Forest Protocol. Like Forest, Wunet is an overlay network that supports unicast and multicast traffic. But Wunet only supports only a rudimentary form of multicast and there is no provision for error control (e.g., dropped bits). It was developed primarily for educational purposes during the Fall 2009 semester for a course in the Computer Science and Engineering Department at Washington University in St. Louis.

A Wunet Example

Wunet Concepts

A Wunet network consists of a set of nodes consisting of hosts and router nodes. Each node has a 32-bit virtual node address (vaddr). By convention hosts have virtual node addresses between 1 and 99, and routers have addresses that are typically multiples of 100 (e.g., 300). A multicast address is any 32-bit address with its high-order bit set (i.e., any decimal number greater than 2^31-1 = 2,147,483,647).

  • Virtual Node
    • Vaddr (Virtual address)
  • Vnet (Virtual Network)
    • Vlink (Virtual Link)
  • Subscribe/Unsubscribe

Wunet Features

  • UDP Encapsulation:
    • Each packet is encapsulated in UDP packet
  • Virtual Addresses:
    • There are unicast addresses(e.g., 21, 200) and
    • Multicast addresses(e.g., 2200110011 = x832303BB) addresses.
      • Any address with high-order bit set is mcast addr; i.e., any decimal number greater than 2^31-1 = 2,147,483,647.
  • Packet Types: DATA, SUBSCRIBE, UNSUBSCRIBE
  • Routing:
    • Packets are routed by (vnet, vaddr)
  • Route Learning:
    • A router will add a reverse route for any incoming packet with a source address not found in the routing table
  • Joining/Leaving Multicast Group:
    • A host joins/leaves a multicast group using SUBSCRIBE/UNSUBSCRIBE
  • Multicast tree is formed for each vnet through SUBSCRIBE packets that travel up the multicast tree
  • Missing Routes:
    • Unicast Data: Flood all downstream links when there is no route.
    • Multicast Data: Send subscriptions upstream when there is no route.

Wunet Packet Header

Wunet Tables

LT (Link Table)

RT (Routing Table)

VT (Vnet Table)

ST (Stats Table)

More Wunet Examples

ONL Implementation