![[LISTSERV - the mailing list management classic]](https://www.lsoft.com/images/HDR-LISTSERV-sm.gif)
There are many possible ways to measure the relative "importance" or "size" of LISTSERV sites: number of lists, number of subscribers, number of messages delivered, etc. In most cases, the number of messages delivered is used to rank mailing list managers, because it is the most accurate measurement of the amount of activity on the server. But, depending on what you are looking for, other variables may be more appropriate. There are currently three LISTSERV "Top 20" lists, ranking the various servers according to:
In addition, you can view a list of the Top 20 lists in the network (by number of subscribers).
The statistics are gathered daily by a monitor at L-Soft which polls all the LISTSERV sites that participate in the "open" LISTSERV network over the worldwide Internet. Corporate servers operating in a "closed" environment are not included.
The statistics are organized in monthly reports. The message volume figures are a flat average of the accumulated traffic for the entire month. Thus, a server that delivers 300,000 messages per month will show a daily average of 10,000 messages. In practice, there is a lot less traffic during the weekend, and even during business days there can be significant fluctuations (~30%). The list statistics (number of lists, number of subscribers, largest lists in the network) are measured as of the last day in the month.
For the current month, the message volume figures are averaged based on the number of days that have elapsed. In practice, the figures are not very meaningful in the first few days, especially if the month starts on a weekend. In that case it is best to refer to the previous month for more accurate figures.
A fourth "Top 20" list is available for the more technically oriented: Number of messages generated by the server. This corresponds to the number of mail messages created by the server while processing postings to its mailing lists. LISTSERV delivers its mail using an intelligent mail delivery function called DISTRIBUTE, which improves mail delivery times and reduces bandwidth usage by spreading the delivery chore over scores of participating servers. Each of these servers processes the recipients for its service area (typically its organization or campus). In most cases, DISTRIBUTE simply alters the manner in which the mail is delivered, and the number of messages forwarded to other sites for optimized delivery is roughly equal to the number of messages received by other sites for the same purpose. In some cases, however, this is not the case, either because the server elected to serve a much wider service area than its own organization, or because it is explicitly forwarding all its deliveries to another machine (for instance, many mainframe-based servers forward their mail to a workstation or PC for delivery).
Pos Recipients Site --- ---------- ---- 1 816599 JISCMAIL.AC.UK (Windows Server 2008 R2 Enterprise x64 Edition) 2 475615 LISTS.PSU.EDU (AIX 6.1) 3 388103 NEWSMAIL.WYANOKEGROUP.COM (Windows Server 2008 R2 Standard x64 Edition) 4 334134 LISTSERV.BUFFALO.EDU (Solaris 2.11) 5 330667 LISTSERV.TAMU.EDU (Linux 3.0.101) 6 302927 LISTSERV.MED.CORNELL.EDU (SunOS 5.10) 7 279264 LISTSERV.UGA.EDU (Linux 2.6.32) 8 276568 LISTS.UFL.EDU (Linux 2.6.18) 9 273159 LISTSERV.SYR.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 10 270237 LISTSERV.ICORS.ORG (Windows Server 2008 R2 Datacenter x64 Edition) 11 268491 LSV.UKY.EDU (Windows Server 2003) 12 260501 LSERV.CARDSYS.AT (Linux 2.6.32-39-pve) 13 259085 LISTSERV.UMD.EDU (SunOS 5.10) 14 230509 LISTSERV.UIC.EDU (Linux 2.6.32-504.8.1.el6.x86_64) 15 228107 LISTES.ULAVAL.CA (Linux 2.6.18) 16 226887 LISTSERV.LIV.AC.UK (Linux 2.6.32) 17 218760 H-NET.MSU.EDU (Linux 2.6.32) 18 209167 DISCUSSIONS.EQ.EDU.AU (Linux 2.6.18-404.el5) 19 203777 LISTSERV.ACM.ORG (Windows Server 2008 R2 Datacenter x64 Edition) 20 187397 LISTS.HAWAII.EDU (Linux 2.6.32-573.3.1.el6.x86_64)
Pos Subscribers Site --- ----------- ---- 1 4812221 LISTS.PSU.EDU (AIX 6.1) 2 3566196 LISTES.ULAVAL.CA (Linux 2.6.18) 3 1644649 LSV.UKY.EDU (Windows Server 2003) 4 1571246 LISTSERV.UGA.EDU (Linux 2.6.32) 5 1506619 LISTS.WAYNE.EDU (Linux 2.6.18) 6 1257633 LISTSERV.TAU.AC.IL (Linux 2.6.9) 7 1207079 LISTSERV.CC.KULEUVEN.AC.BE (Linux 2.6.18) 8 1178832 LISTSERV.TAMU.EDU (Linux 3.0.101) 9 1059036 LISTS.UFL.EDU (Linux 2.6.18) 10 1058441 HERMES.GWU.EDU (Linux 2.6.32) 11 1037240 LIST.MSU.EDU (Linux 3.0.34) 12 1025559 LISTSERV.UTORONTO.CA (Linux 2.6.18) 13 1020873 LISTS.UMN.EDU (Solaris 2.10) 14 966934 LISTSERV.BUFFALO.EDU (Solaris 2.11) 15 914887 LISTSERV.ND.EDU (Linux 2.6.18) 16 846205 LISTSERV.UA.EDU (Linux 3.0.82) 17 840086 CUVMC.AIS.COLUMBIA.EDU (VM/SP 4.0) 18 758425 LISTSERV.MIAMIOH.EDU (Windows Server 2012 R2 Standard x64 Edition) 19 751295 LISTS.ASU.EDU (Linux 2.6.18) 20 707974 LISTSERV.SYR.EDU (Windows Server 2008 R2 Enterprise x64 Edition)
Pos Lists Site --- ----- ---- 1 56765 LSV.UKY.EDU (Windows Server 2003) 2 35453 LISTS.PSU.EDU (AIX 6.1) 3 25800 LISTES.ULAVAL.CA (Linux 2.6.18) 4 12026 LISTSERV.TAU.AC.IL (Linux 2.6.9) 5 9788 LISTS.CLEMSON.EDU (Linux 2.6.18) 6 9599 LISTS.UFL.EDU (Linux 2.6.18) 7 8328 LISTSERV.CC.KULEUVEN.AC.BE (Linux 2.6.18) 8 6887 MARIST (VM/SP 2.0) 9 6824 LISTSERV.UGA.EDU (Linux 2.6.32) 10 6414 LISTSERV.TECHNION.AC.IL (Linux 2.6.32) 11 6226 LISTSERV.TAMU.EDU (Linux 3.0.101) 12 6160 LISTSERV.MIAMIOH.EDU (Windows Server 2012 R2 Standard x64 Edition) 13 6023 LISTS.UMN.EDU (Solaris 2.10) 14 5158 LISTSERV.LIV.AC.UK (Linux 2.6.32) 15 4273 LISTSERV.NODAK.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 16 4006 LISTSERV.ND.EDU (Linux 2.6.18) 17 3906 LISTSERV.MILLERSVILLE.EDU (Linux 2.6.32) 18 3359 YORKU.CA (Linux 2.6.32) 19 3329 LISTSERV.SYR.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 20 3291 LISTSERV.UTORONTO.CA (Linux 2.6.18)
Pos Recipients Site --- ---------- ---- 1 792659 JISCMAIL.AC.UK (Windows Server 2008 R2 Enterprise x64 Edition) 2 470735 LISTS.PSU.EDU (AIX 6.1) 3 330033 LISTSERV.BUFFALO.EDU (Solaris 2.11) 4 328602 LISTSERV.TAMU.EDU (Linux 3.0.101) 5 302318 LISTSERV.MED.CORNELL.EDU (SunOS 5.10) 6 273060 LISTSERV.UGA.EDU (Linux 2.6.32) 7 272790 LISTS.UFL.EDU (Linux 2.6.18) 8 264664 LSV.UKY.EDU (Windows Server 2003) 9 263780 LISTSERV.ICORS.ORG (Windows Server 2008 R2 Datacenter x64 Edition) 10 241985 LISTSERV.UMD.EDU (SunOS 5.10) 11 237943 LISTSERV.SYR.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 12 230003 LISTSERV.UIC.EDU (Linux 2.6.32-504.8.1.el6.x86_64) 13 227875 LISTES.ULAVAL.CA (Linux 2.6.18) 14 219433 LISTSERV.LIV.AC.UK (Linux 2.6.32) 15 216635 H-NET.MSU.EDU (Linux 2.6.32) 16 209018 DISCUSSIONS.EQ.EDU.AU (Linux 2.6.18-404.el5) 17 186393 LISTS.HAWAII.EDU (Linux 2.6.32-573.3.1.el6.x86_64) 18 182910 LISTS.UMN.EDU (Solaris 2.10) 19 182756 LISTSERV.REDIRIS.ES (Linux 2.6.32-504.3.3.el6.x86_64) 20 174408 LISTSERV.DARTMOUTH.EDU (Windows Server 2008 R2 Enterprise x64 Edition)
Pos Subscribers Site --- ----------- ---- 1 300761 COMPUTING@LIST.MSU.EDU (Linux 3.0.34) 2 299633 NYSTEACHING@LISTSERV.NYSED.GOV (AIX 7.1) 3 109575 COMNET@HERMES.GWU.EDU (Linux 2.6.32) 4 79693 CAREERCENTERUPDATE@LISTSERV.UGA.EDU (Linux 2.6.32) 5 62696 EXCEL@LISTSERV.UTA.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 6 41610 SAFETYNOTICE@LISTSERV.UC.EDU (Windows Server 2012 R2 Datacenter x64 Edition) 7 40988 OPSWNEWS@LISTSERV.NYSED.GOV (AIX 7.1) 8 34961 ASMSU@LIST.MSU.EDU (Linux 3.0.34) 9 34588 TCUATHLETICSDIRECTOR@LISTSERV.TCU.EDU (Windows Server 2012 R2 Standard x64 Edition) 10 33621 L-SMEAL-REPORT@LISTS.PSU.EDU (AIX 6.1) 11 33588 EDREV@LISTS.ASU.EDU (Linux 2.6.18) 12 31565 L-FACSTAFF-NEWSWIRE-UP@LISTS.PSU.EDU (AIX 6.1) 13 30849 FOCIS_GROUP@LISTS.WAYNE.EDU (Linux 2.6.18) 14 28258 L-THON-NEWS@LISTS.PSU.EDU (AIX 6.1) 15 27850 HALLCOLIBRARY-L@LISTSERV.UGA.EDU (Linux 2.6.32) 16 27728 RECREATION@LISTSERV.MIAMIOH.EDU (Windows Server 2012 R2 Standard x64 Edition) 17 27427 VOLUPDATE@LISTSERV.UTK.EDU (Solaris 2.10) 18 26415 PARENTS@LISTSERV.TAMU.EDU (Linux 3.0.101) 19 25431 CSTORE@LIST.MSU.EDU (Linux 3.0.34) 20 24988 NCHPAD-NEWS@LISTSERV.UAB.EDU (Solaris 2.9)