rfc1128.ps

RFC 的详细文档！

300 1108 1950 10 (including the DAYTIME protocol [POS83a], TIME Protocol [POS83b], ICMP Timestamp message)fjt
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300 991 1950 12 (synchronization directly into the routing protocol using algorithms similar to NTP [MIL83]. The)fjt
300 933 529 4 (Unix 4.3bsd time daemon )fjt
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829 933 111 0 (timed)fjt
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939 933 1311 11 ( uses a single master-time daemon to measure offsets of a number)fjt
300 875 1950 14 (of slave hosts and send periodic corrections to them [GUS85]. However, these protocols do not)fjt
300 817 1846 11 (include engineered algorithms to compensate for the effects of statistical delay variation)fjt
2146 817 87 1 (s en)fjt
2234 817 17 0 (-)fjt
300 758 1928 12 (countered on wide-area networks and are unsuitable for precision time distribution throughout th)fjt
2228 758 22 0 (e)fjt
300 700 167 0 (Internet.)fjt
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300 606 83 0 (1.3.)fjt
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300 516 1867 18 (In this paper to synchronize frequency means to adjust the clocks in the network to run at the s)fjt
2167 516 83 0 (ame)fjt
300 457 1911 17 (frequency, to synchronize time means to set the clocks so that all agree at a particular epoch wi)fjt
2211 457 39 0 (th)fjt
300 399 1950 14 (respect to UTC, as provided by national standards, and to synchronize clocks means to synchronize)fjt
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300 2979 227 1 (RFC 1128)fjt
805 2979 941 5 (Performance of the Network Time Protocol)fjt
1948 2979 302 1 (October 1989)fjt
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300 279 100 0 (Mills)fjt
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300 2335 1950 13 (them in both frequency and time. A clock synchronization subnet operates by measuring clock)fjt
300 2277 1771 15 (offsets between the various peers in the subnet and so is vulnerable to statistical delay vari)fjt
2071 2277 180 1 (ations on)fjt
300 2219 1950 14 (the various transmission paths between them. In the Internet the paths involved can have wide)fjt
300 2160 1773 13 (variations in delay and reliability, while the routing algorithms can select landline or satell)fjt
2073 2160 178 1 (ite paths,)fjt
300 2102 1574 11 (public network or dedicated links or even suspend service without prior notice.)fjt
300 2011 1776 9 (In statistically noisy subnets accurate time synchronization requires carefully engineered)fjt
2076 2011 174 1 ( filtering)fjt
300 1953 1876 13 (and selection algorithms and the use of redundant resources and diverse transmission paths, w)fjt
2176 1953 75 0 (hile)fjt
300 1895 1876 10 (accurate frequency synchronization requires finely tuned oscillator tracking loops and mult)fjt
2176 1895 75 0 (iple)fjt
300 1837 1881 14 (phase comparisons over relatively long periods of time. For instance, while only a few comparis)fjt
2181 1837 69 0 (ons)fjt
300 1778 1821 17 (are usually adequate to resolve local time for an Internet host to within a few tens of millise)fjt
2121 1778 129 0 (conds,)fjt
300 1720 1934 16 (dozens of measurements over many hours are required to resolve frequency to within a few tens o)fjt
2234 1720 17 0 (f)fjt
300 1662 424 2 (milliseconds per day.)fjt
300 1567 1830 17 (In NTP the roundtrip delay and clock offset relative to a peer time server are calculated as fo)fjt
2130 1567 120 0 (llows.)fjt
300 1509 1565 13 (Number the times of sending and receiving NTP messages as shown in Figure 1)fjt
1865 1509 152 3 ( and let )fjt
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931 1451 1319 12 ( are the contents of the four most recent timestamps as above. The)fjt
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1044 1392 1018 9 (of the receiving host relative to the sending peer is:)fjt
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