On Thu, Feb 21, 2008 at 9:43 PM, Brian Dickson <[EMAIL PROTECTED]> wrote: > The short list of things that I think need further testing or analysis > or experience, regarding loss > or delay to the first packet: > ntp (think about it!)
Brian, Say, that's a good one. NTP clients querying servers through a TRRP path with oscillate the servers between eligible and ineligible each time the delay between NTP queries gets long enough to cause the address to time out of the ITR causing what the NTP client will perceive as excessive delay and jitter. Solving this in the short term requires no changes to NTP but it does require some attention to configuration for those who choose to be early adopters of TRRP space. Far-away NTP servers won't be usable over a TRRP path so you'll need a machine on BGP routable space to make those far-away queries and then you'll have to query that machine over the local routing infrastructure that doesn't pass through BGP or TRRP. Fortunately, TRRP's ETRs already meet this criteria and many machines capable of running a GRE endpoint are also capable of running NTP. In the long term, NTP client software could be adjusted to notice the unexpected delay phenomenon and either shorten the time between queries to the point where the destination stays in the ITR's cache or recognize the delay as transient and retry a few seconds later ignoring the transient delayed result. The ITR will generally only have to re-cache the bottom-level component, so that cache oscillation shouldn't be harmful. This will be an issue for every map-encap scheme that relies on caching. > snmp > snmptrap Generally local; outside TRRP's area of effect. > l2tp Don't know for sure but I don't think there's a problem with l2tp or pptp over TRRP-managed address space. VPN protocols are generally already designed to work over nasty, unpredictable networks. > all the various *lm things (licence managers) - how many IT help desks > to we want to anger at once, really? Generally local; outside TRRP's area of effect. Regards, Bill Herrin -- William D. Herrin [EMAIL PROTECTED] [EMAIL PROTECTED] 3005 Crane Dr. Web: <http://bill.herrin.us/> Falls Church, VA 22042-3004 -- to unsubscribe send a message to [EMAIL PROTECTED] with the word 'unsubscribe' in a single line as the message text body. archive: <http://psg.com/lists/rrg/> & ftp://psg.com/pub/lists/rrg
