common logarithm

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common logarithm

[¦käm·ən ′läg·ə‚rith·əm]
(mathematics)
The exponent in the representation of a number as a power of 10. Also known as Briggsian logarithm; Briggs' logarithm.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
References in periodicals archive ?
Each entry of MRT's log tables contains a 32-bit digest and a 32-bit marking field.
As for the computing time of a path reconstruction, both MRT and MORE require that a router uses the request packet's digest to find its previously stored marking field in the log table. However, their routers' log tables are unsorted, so they need an exhaustive search.
If packet numbers exceed a router's storage limit, its log tables will be refreshed.
Consequently, the size of their log tables grows with the number of logged packets.
Instead, we use logged packets' other fields to store the log tables' numbers.
With only 2 MB storage requirement, the chance of a router refreshing our log tables is quite low.
It is because our log tables allow more entries on the routers whose degrees are under the threshold value 10, and because we do not use fixed-size tables.
Notations [R.sub.i]: {[R.sub.1], [R.sub.2], ..., [R.sub.i], ..., [R.sub.x]}, routers in a network D([R.sub.i]): The degree of [R.sub.i], that is, the number of [R.sub.i]'s adjacent routers [P.sub.j]: A packet j [UI.sub.i]: The upstream interface number of router [R.sub.i] [P.sub.j] x mark: Marking field of [P.sub.j] [P.sub.j] x srcIP: [P.sub.j]'s source IP m: A log table with m entries [H.sub.table](*): A hash function with hashed value ranging from 0 to n - 1, where n denotes the number of log tables [[T.sup.s.sub.k], [T.sup.s.sub.k] denotes log table k's created [T.sup.f.sub.k]): time; and [T.sup.f.sub.k] denotes k's full time, where s, f = 0, ..., t, ..., [infinity].
When a router receives the packet, it uses the packet's destination IP as an index to choose a log table to log this mark.
If a router receives a packet whose mark is larger than 65535, the router hashes the packet's destination IP and uses the hash value to assign a log table; it also hashes the packet's mark to compute an index value.
Each router's route info consists of the interface number where the packet enters; its log table's information; and its degrees.
As shown in Table 2(a), a router's log table [HT.sub.k] consists of three parts: the top row is used to indicate the table's creation time [T.sup.s.sub.k] and fill-up time [T.sup.f.sub.k]; the left column indicates the index of each entry; the right column stores packets' marks.

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