49 lines
1.3 KiB
Go
49 lines
1.3 KiB
Go
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package p2p
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// this file implements time related code for syncing the unsyncronised servers
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// yes, this project contains a local averaging distributed clock syncronisation algorithm
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import "time"
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//
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// org = Origin Timestamp (client send time)
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// rec = Receive Timestamp (server receive time)
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// xmt = Transmit Timestamp (server reply time)
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// dst = Destination Timestamp (client receive time)
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func rtt(org, rec, xmt, dst time.Time) time.Duration {
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// round trip delay time rtt = (dst-org) - (xmt-rec)
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a := dst.Sub(org)
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b := xmt.Sub(rec)
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rtt := a - b
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if rtt < 0 {
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rtt = 0
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}
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return rtt
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}
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// all inputs are in micro secs,output is in nsec
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func rtt_micro(org, rec, xmt, dst int64) time.Duration {
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// round trip delay time rtt = (dst-org) - (xmt-rec)
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a := dst - org
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b := xmt - rec
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rtt := a - b
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if rtt < 0 {
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rtt = 0
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}
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return time.Duration(rtt * 1000)
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}
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func offset(org, rec, xmt, dst time.Time) time.Duration {
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// local clock offset = ((rec-org) + (xmt-dst)) / 2
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a := rec.Sub(org)
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b := xmt.Sub(dst)
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return (a + b) / time.Duration(2)
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}
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// all inputs are in micro secs, output is in nsec
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func offset_micro(org, rec, xmt, dst int64) time.Duration {
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// local clock offset = ((rec-org) + (xmt-dst)) / 2
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a := rec - org
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b := xmt - dst
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return time.Duration((a+b)*1000) / time.Duration(2)
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}
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