Dear Wiki user,

You have subscribed to a wiki page or wiki category on "River Wiki" for change 
notification.

The "RiverOnTheInternet" page has been changed by PeterFirmstone:
http://wiki.apache.org/river/RiverOnTheInternet?action=diff&rev1=16&rev2=17

  ## page was renamed from InternetJini
- 
  Please share your ideas.
  
  = Proposal for improving the deployability of river on the internet. =
+ Registry discovery current only works on network infrastructure supporting 
multicast and broadcast. Most ISPs do not support multicast, and broadcast will 
only be limited to the LAN or network subnet.
- Registry discovery current only works on network infrastructure supporting 
multicast and broadcast.
- Most ISPs do not support multicast, and broadcast will only be limited to the 
LAN or network subnet.
  
+ The ISP (cable/adsl) provides the customer with connection to the internet.  
Optionally provides the customer with preconfigured CPE.  The CPE providing the 
connection has varing levels of firewall and NAT options, not always user 
configurable.
- The ISP (cable/adsl) provides the customer with connection to the internet. 
- Optionally provides the customer with preconfigured CPE. 
- The CPE providing the connection has varing levels of firewall and NAT 
options, not always user configurable.
  
  = DNS-SRV =
  To use DNS-SRV records to locate and discover lookup services (Service 
Registrar's like Reggie).
@@ -18, +14 @@

  To use DNS-SRV records to locate codebase servers at runtime and provide 
redundancy of codebase servers.
  
  = behind NAT services =
- 
  == UPNP firewall configuration ==
  Domestic ADSL modems (CPE=customer premise equipment) usually come with a 
UPNP service to activate DNAT. The availability of this UPNP service is 
configurable. So not guarantueed.
  
  == Reversing the connections ==
+ One solution would be to convert 'passive' services behind a NAT into a 
polling service, polling for work from a proxy on the internet.  This proxy 
would consist of a blocking queue, queuing the jeri calls until they are 
serviced by the hidden server and replied. The Mekong implementation covers 
this scenario.
- One solution would be to convert 'passive' services behind a NAT into a 
polling service, polling for work from a proxy on the internet. 
- This proxy would consist of a blocking queue, queuing the jeri calls until 
they are serviced by the hidden server and replied.
- The Mekong implementation covers this scenario.
  
  The mekong solution piggybacks on jeri connections in the other direction. 
The problem there is the firewall options on the CPE and/or personal firewall 
blocking outgoing connections.
  
  The only connections not blocked are http and https, so implementation of the 
poller transport in jeri http or https has an advantage.
  
+ == UDT - UDP Data Transfer ==
+ UDT is a UDP based data transfer protocol, implemented for high performance 
communications over wide area networks.  One particular advantage of UDT is the 
ability to multiplex on a single port, so any number of Sockets can share a 
single network port, rather than having to open a new port for each Socket.  
Key to the implementation is SocketID, used to distinguish Sockets sharing a 
port.
+ 
+ By taking advantage of UDT multiplexing, a jvm residing in a private network 
computer only needs one port redirected on the NAT or firewall, multiple Jini 
services intended for the internet could be provided from one jvm and made 
available over a single UDP Firewall port.
+ 
+ If a client contacts a public server, then that server may utilise handback 
services from the client, since the port mapping doesn't change.  However if a 
client behind a NAT registers a service with a lookup service, even if it keeps 
the connection alive, other clients may not be able to utilise those services, 
in some cases they will, but it depends on the NAT hardware and firewall 
configuration.
+ 
+ There are several ways to open a NAT port, using STUN, UPNP, NAT-PMP or 
manual configuration. UDT also supports rendezvous connection setup.
+ 
+ UDT won't solve all NAT issues however.
+ 
+ http://udt.sourceforge.net/
+ 

Reply via email to