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INN FAQ Part 6

NOTE: The maintainers of the INN FAQ stopped publishing in December 1997.
An important update to this topic is provided by Mib Software in the Usenet RKT for Subscribers.

Subject: (6.25) Speed up NNTP Transfers ("Streaming NNTP")

Normal NNTP uses the following scheme to transfer articles:

Sender                    Receiver
  ---> Ihave <some Message>
   Ok send it to me       <---
  --->  sends the actual message 
   Says 'this was ok'    <---

This procedure uses 2*RTT on the link (rtt = round trip time) plus time
for the actual article transfer. Jerry Aguirre has rewritten NNTP code
so that it now sends a list of message ids to remote which checks it and
returns a value if it is to be sent. With each message sent Streaming NNTP
also sends a new message-id to check so that the flow of news keeps

Advantages of Streaming NNTP are
- Fast even on lines with a high rtt (e.g. satellite links)
- faster than normal nntp
- compatible as innxmit has a autofallback to normal nntp

Disadvantages are
- INN gets more compute intensive
- Streaming NNTP can fill a 64kB line that much that working
over it via telnet gets a real pain.


[Source: INN FAQ Part 6 Archive-name: usenet/software/inn-faq/part6]
[Last Changed: $Date: 1997/07/01 01:25:41 $ $Revision: 2.21 $]
[Copyright: 1997 Heiko Rupp, portions by Tom Limoncelli, Rich Salz, et al.]