![[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 631593 JISCMAIL.AC.UK (Windows Server 2008 R2 Enterprise x64 Edition) 2 383978 LISTS.PSU.EDU (AIX 6.1) 3 379972 NEWSMAIL.WYANOKEGROUP.COM (Windows Server 2008 R2 Standard x64 Edition) 4 302041 LISTSERV.BUFFALO.EDU (Solaris 2.11) 5 278493 LISTSERV.MED.CORNELL.EDU (SunOS 5.10) 6 274554 LSERV.CARDSYS.AT (Linux 2.6.32-39-pve) 7 235008 LISTSERV.ICORS.ORG (Windows Server 2008 R2 Datacenter x64 Edition) 8 209916 LSV.UKY.EDU (Windows Server 2003) 9 208152 LISTSERV.ACM.ORG (Windows Server 2008 R2 Datacenter x64 Edition) 10 203342 LISTSERV.REDIRIS.ES (Linux 2.6.32-504.3.3.el6.x86_64) 11 198593 LISTSERV.UMD.EDU (SunOS 5.10) 12 197741 LISTSERV.UGA.EDU (Linux 2.6.32) 13 196749 LISTSERV.SYR.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 14 194363 LISTS.UFL.EDU (Linux 2.6.18) 15 192677 LISTSERV.TAMU.EDU (Linux 3.0.101) 16 160169 LISTSERV.LIV.AC.UK (Linux 2.6.32) 17 157145 PO.MISSOURI.EDU (Windows Server 2012 R2 Standard x64 Edition) 18 153759 LISTSERV.UIC.EDU (Linux 2.6.32-504.8.1.el6.x86_64) 19 147229 H-NET.MSU.EDU (Linux 2.6.32) 20 145765 LISTS.HAWAII.EDU (Linux 2.6.32-573.3.1.el6.x86_64)
Pos Subscribers Site --- ----------- ---- 1 4833777 LISTS.PSU.EDU (AIX 6.1) 2 4349501 LISTES.ULAVAL.CA (Linux 2.6.18) 3 1644649 LSV.UKY.EDU (Windows Server 2003) 4 1597099 LISTSERV.UGA.EDU (Linux 2.6.32) 5 1499316 LISTS.WAYNE.EDU (Linux 2.6.18) 6 1272168 LISTSERV.TAU.AC.IL (Linux 2.6.9) 7 1207079 LISTSERV.CC.KULEUVEN.AC.BE (Linux 2.6.18) 8 1188293 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 1025980 LIST.MSU.EDU (Linux 3.0.34) 12 1020559 LISTS.UMN.EDU (Solaris 2.10) 13 945948 LISTSERV.BUFFALO.EDU (Solaris 2.11) 14 903987 LISTSERV.ND.EDU (Linux 2.6.18) 15 854396 LISTSERV.UA.EDU (Linux 3.0.82) 16 845543 CUVMC.AIS.COLUMBIA.EDU (VM/SP 4.0) 17 835283 LISTSERV.UTORONTO.CA (Linux 2.6.18) 18 751295 LISTS.ASU.EDU (Linux 2.6.18) 19 724273 LISTSERV.MIAMIOH.EDU (Windows Server 2012 R2 Standard x64 Edition) 20 701470 LISTSERV.SYR.EDU (Windows Server 2008 R2 Enterprise x64 Edition)
Pos Lists Site --- ----- ---- 1 56765 LSV.UKY.EDU (Windows Server 2003) 2 35482 LISTS.PSU.EDU (AIX 6.1) 3 32054 LISTES.ULAVAL.CA (Linux 2.6.18) 4 12213 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 6874 LISTSERV.UGA.EDU (Linux 2.6.32) 9 6379 LISTSERV.TECHNION.AC.IL (Linux 2.6.32) 10 6348 MARIST (VM/SP 2.0) 11 6261 LISTSERV.TAMU.EDU (Linux 3.0.101) 12 6167 LISTSERV.MIAMIOH.EDU (Windows Server 2012 R2 Standard x64 Edition) 13 5990 LISTS.UMN.EDU (Solaris 2.10) 14 5177 LISTSERV.LIV.AC.UK (Linux 2.6.32) 15 4299 LISTSERV.NODAK.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 16 4012 LISTSERV.ND.EDU (Linux 2.6.18) 17 3903 LISTSERV.MILLERSVILLE.EDU (Linux 2.6.32) 18 3364 YORKU.CA (Linux 2.6.32) 19 3308 LISTSERV.UTORONTO.CA (Linux 2.6.18) 20 3302 LISTSERV.SYR.EDU (Windows Server 2008 R2 Enterprise x64 Edition)
Pos Recipients Site --- ---------- ---- 1 610935 JISCMAIL.AC.UK (Windows Server 2008 R2 Enterprise x64 Edition) 2 379170 LISTS.PSU.EDU (AIX 6.1) 3 297666 LISTSERV.BUFFALO.EDU (Solaris 2.11) 4 277854 LISTSERV.MED.CORNELL.EDU (SunOS 5.10) 5 229446 LISTSERV.ICORS.ORG (Windows Server 2008 R2 Datacenter x64 Edition) 6 206959 LSV.UKY.EDU (Windows Server 2003) 7 200404 LISTSERV.REDIRIS.ES (Linux 2.6.32-504.3.3.el6.x86_64) 8 193118 LISTSERV.UGA.EDU (Linux 2.6.32) 9 190831 LISTSERV.TAMU.EDU (Linux 3.0.101) 10 190816 LISTS.UFL.EDU (Linux 2.6.18) 11 184321 LISTSERV.UMD.EDU (SunOS 5.10) 12 166471 LISTSERV.SYR.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 13 156640 PO.MISSOURI.EDU (Windows Server 2012 R2 Standard x64 Edition) 14 154216 LISTSERV.LIV.AC.UK (Linux 2.6.32) 15 153259 LISTSERV.UIC.EDU (Linux 2.6.32-504.8.1.el6.x86_64) 16 145694 H-NET.MSU.EDU (Linux 2.6.32) 17 143470 LISTS.HAWAII.EDU (Linux 2.6.32-573.3.1.el6.x86_64) 18 140390 LISTS.UMN.EDU (Solaris 2.10) 19 132405 LISTSERV.UA.EDU (Linux 3.0.82) 20 125347 LISTSERV.NODAK.EDU (Windows Server 2008 R2 Enterprise x64 Edition)
Pos Subscribers Site --- ----------- ---- 1 300759 COMPUTING@LIST.MSU.EDU (Linux 3.0.34) 2 299689 NYSTEACHING@LISTSERV.NYSED.GOV (AIX 7.1) 3 109575 COMNET@HERMES.GWU.EDU (Linux 2.6.32) 4 79664 CAREERCENTERUPDATE@LISTSERV.UGA.EDU (Linux 2.6.32) 5 62694 EXCEL@LISTSERV.UTA.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 6 41011 OPSWNEWS@LISTSERV.NYSED.GOV (AIX 7.1) 7 40299 SAFETYNOTICE@LISTSERV.UC.EDU (Windows Server 2012 R2 Datacenter x64 Edition) 8 34964 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 31170 L-FACSTAFF-NEWSWIRE-UP@LISTS.PSU.EDU (AIX 6.1) 13 30849 FOCIS_GROUP@LISTS.WAYNE.EDU (Linux 2.6.18) 14 28255 L-THON-NEWS@LISTS.PSU.EDU (AIX 6.1) 15 27932 HALLCOLIBRARY-L@LISTSERV.UGA.EDU (Linux 2.6.32) 16 27728 RECREATION@LISTSERV.MIAMIOH.EDU (Windows Server 2012 R2 Standard x64 Edition) 17 27428 VOLUPDATE@LISTSERV.UTK.EDU (Solaris 2.10) 18 26414 PARENTS@LISTSERV.TAMU.EDU (Linux 3.0.101) 19 25428 CSTORE@LIST.MSU.EDU (Linux 3.0.34) 20 25092 CCS-CEVAL@LISTSERV.UOGUELPH.CA (Linux 2.6.18)