peltz@cerl.uiuc.edu (Steve Peltz) (12/07/89)
I just read the RFC 977, and one thing really puzzled me. When asking for new articles or newsgroups since a particular date, how do you find out what time the server thinks it is? In a perfect world, this wouldn't be a problem, but with the amount of traffic coming in, there's almost sure to be a few articles slip by because of time differences. Either: in the reply to the NEWNEWS or NEWGROUPS commands, repond with the current date and time; Or: (for NEWNEWS, anyway) be able to ask for all message ids that were added after a given message id (which would, presumably, be the last message id that was received the last time a NEWNEWS had been done). -- Steve Peltz (almost) CFI-G "Monticello traffic, Glider 949 landing 18, full stop"
brian@ucsd.Edu (Brian Kantor) (12/07/89)
In article <1989Dec7.050042.18935@ux1.cso.uiuc.edu> peltz@cerl.uiuc.edu (Steve Peltz) writes: >I just read the RFC 977, and one thing really puzzled me. When asking for >new articles or newsgroups since a particular date, how do you find out what >time the server thinks it is? In a perfect world, this wouldn't be a problem, >but with the amount of traffic coming in, there's almost sure to be a few >articles slip by because of time differences. You don't currently, except by other means. The NNTP herald when you first connect has usually got the date and time in it, and you could conceivably parse that out and calculate an offset from your local system's concept of time, but that would be an obscene kludge. You could use NTP to query the server, if you both support it. You can use ICMP timestamps if you're using an IP network for NNTP access. However, we recognize this problem and in an upcoming revision to the NNTP spec we'll be providing a DATE or TIME command that returns the server's estimate of what time it is. - Brian
bob@MorningStar.Com (Bob Sutterfield) (12/08/89)
NNTP is the wrong place to manage or communicate time if you intend to use the time for something that matters to you. If two machines each care what time the other has, they should use NTP to coordinate with each other, and themselves to an outside standard Real Time. The news software should only need to worry about whatever its local clock claims the time to be. Are there any existing or projected uses of netnews that require sub-millisecond time coordination between two hosts? If so, how do you tell whether or not you've achieved it if you're not using something at least as good as NTP?