![[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 843343 JISCMAIL.AC.UK (Windows Server 2008 R2 Enterprise x64 Edition) 2 528390 LISTSERV.TAMU.EDU (Linux 3.0.101) 3 471194 LISTS.PSU.EDU (AIX 6.1) 4 325699 LSERV.CARDSYS.AT (Linux 4.4.98-6-pve) 5 304474 LISTSERV.LIV.AC.UK (Linux 2.6.32) 6 300759 LISTSERV.SYR.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 7 300114 LSV.UKY.EDU (Windows Server 2012 R2 Datacenter x64 Edition) 8 294803 LISTES.ULAVAL.CA (Linux 2.6.18) 9 268722 LISTSERV.BUFFALO.EDU (Solaris 2.11) 10 251378 LISTSERV.UGA.EDU (Linux 2.6.32) 11 229229 DIGITAL.ANNEXBUSINESSMEDIA.COM (Linux 3.13.0-32-generic) 12 226876 LISTS.UFL.EDU (Linux 2.6.18) 13 223070 LISTS.UCDENVER.EDU (Windows Server 2012 R2 Standard x64 Edition) 14 219569 LISTSERV.ACM.ORG (Windows Server 2012 R2 Datacenter x64 Edition) 15 215255 LISTSERV.UMD.EDU (SunOS 5.10) 16 212851 LIST.ETSI.ORG (Windows Server 2016 Datacenter x64 Edition + LSMTP V1.1b) 17 198698 LISTSERV.REDIRIS.ES (Linux 2.6.32-504.3.3.el6.x86_64) 18 186931 DISCUSSIONS.EQ.EDU.AU (Linux 2.6.18-404.el5) 19 168807 LIST.UVM.EDU (Linux 2.6.32) 20 162841 LISTS.HAWAII.EDU (Linux 2.6.32-696.16.1.el6.x86_64)
Pos Subscribers Site --- ----------- ---- 1 5273674 LISTS.PSU.EDU (AIX 6.1) 2 3634619 LISTES.ULAVAL.CA (Linux 2.6.18) 3 2022985 LS.KULEUVEN.BE (Linux 2.6.32) 4 1572257 LISTS.WAYNE.EDU (Linux 2.6.32) 5 1434226 LSV.UKY.EDU (Windows Server 2012 R2 Datacenter x64 Edition) 6 1347275 LISTSERV.UGA.EDU (Linux 2.6.32) 7 1341282 LISTSERV.TAU.AC.IL (Linux 2.6.9) 8 1332123 LISTSERV.TAMU.EDU (Linux 3.0.101) 9 1283912 LISTSERV.UTORONTO.CA (Linux 2.6.18) 10 1059036 LISTS.UFL.EDU (Linux 2.6.18) 11 1023700 LISTSERV.BUFFALO.EDU (Solaris 2.11) 12 998215 LISTS.UMN.EDU (Linux 2.6.32) 13 944029 LIST.MSU.EDU (Linux 3.10.0) 14 824982 LISTSERV.UH.EDU (Linux 3.10.0) 15 818258 CUVMC.AIS.COLUMBIA.EDU (VM/SP 4.0) 16 790532 LISTSERV.MIAMIOH.EDU (Windows Server 2012 R2 Standard x64 Edition) 17 768077 LISTSERV.NODAK.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 18 748333 LISTSERV.UA.EDU (Linux 3.0.101) 19 736798 LISTSERV.SYR.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 20 729248 LISTSERV.ECU.EDU (Windows Server 2008 R2 Enterprise x64 Edition)
Pos Lists Site --- ----- ---- 1 27201 LISTES.ULAVAL.CA (Linux 2.6.18) 2 16854 LISTS.PSU.EDU (AIX 6.1) 3 14064 LSV.UKY.EDU (Windows Server 2012 R2 Datacenter x64 Edition) 4 13425 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 8006 LISTSERV.TECHNION.AC.IL (Linux 2.6.32) 8 6996 MARIST (VM/SP 2.0) 9 6822 LISTSERV.TAMU.EDU (Linux 3.0.101) 10 6597 LISTSERV.MIAMIOH.EDU (Windows Server 2012 R2 Standard x64 Edition) 11 6487 LISTSERV.LIV.AC.UK (Linux 2.6.32) 12 5721 LISTSERV.MILLERSVILLE.EDU (Linux 2.6.32) 13 5486 LISTS.UMN.EDU (Linux 2.6.32) 14 5292 LISTSERV.UGA.EDU (Linux 2.6.32) 15 4411 LISTSERV.NODAK.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 16 4345 LISTSERV.UTORONTO.CA (Linux 2.6.18) 17 4147 LS.KULEUVEN.BE (Linux 2.6.32) 18 3891 LISTS.QUEENSU.CA (Solaris 2.10) 19 3773 LISTSERV.SYR.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 20 3602 YORKU.CA (Linux 2.6.32)
Pos Recipients Site --- ---------- ---- 1 813974 JISCMAIL.AC.UK (Windows Server 2008 R2 Enterprise x64 Edition) 2 527127 LISTSERV.TAMU.EDU (Linux 3.0.101) 3 466315 LISTS.PSU.EDU (AIX 6.1) 4 297445 LSV.UKY.EDU (Windows Server 2012 R2 Datacenter x64 Edition) 5 294659 LISTES.ULAVAL.CA (Linux 2.6.18) 6 291039 LISTSERV.LIV.AC.UK (Linux 2.6.32) 7 264120 LISTSERV.BUFFALO.EDU (Solaris 2.11) 8 259043 LISTSERV.SYR.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 9 245848 LISTSERV.UGA.EDU (Linux 2.6.32) 10 224359 LISTS.UFL.EDU (Linux 2.6.18) 11 223000 LISTS.UCDENVER.EDU (Windows Server 2012 R2 Standard x64 Edition) 12 212173 LIST.ETSI.ORG (Windows Server 2016 Datacenter x64 Edition + LSMTP V1.1b) 13 195877 LISTSERV.REDIRIS.ES (Linux 2.6.32-504.3.3.el6.x86_64) 14 195704 LISTSERV.UMD.EDU (SunOS 5.10) 15 186735 DISCUSSIONS.EQ.EDU.AU (Linux 2.6.18-404.el5) 16 167137 LIST.UVM.EDU (Linux 2.6.32) 17 161962 LISTS.HAWAII.EDU (Linux 2.6.32-696.16.1.el6.x86_64) 18 156596 LISTSERV.ICORS.ORG (Windows Server 2012 R2 Datacenter x64 Edition) 19 152697 LISTS.UMN.EDU (Linux 2.6.32) 20 143734 LISTSERV.UCONN.EDU (Windows Server 2012 R2 Standard x64 Edition)
Pos Subscribers Site --- ----------- ---- 1 300656 COMPUTING@LIST.MSU.EDU (Linux 3.10.0) 2 62440 EXCEL@LISTSERV.UTA.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 3 54050 AMIS-CNRS-INTERNATIONAL-L@IN2P3.FR (Linux 3.10.0) 4 41755 OPSWNEWS@LISTSERV.NYSED.GOV (AIX 7.1) 5 38964 CAREERCENTERUPDATE@LISTSERV.UGA.EDU (Linux 2.6.32) 6 38880 SAFETYNOTICE@LISTSERV.UC.EDU (Windows Server 2012 R2 Datacenter x64 Edition) 7 35728 CMU-BASKETBALL@LS2.CMICH.EDU (Linux 3.10.0) 8 34587 TCUATHLETICSDIRECTOR@LISTSERV.TCU.EDU (Windows Server 2012 R2 Standard x64 Edition) 9 33610 L-SMEAL-REPORT@LISTS.PSU.EDU (AIX 6.1) 10 30836 FOCIS_GROUP@LISTS.WAYNE.EDU (Linux 2.6.32) 11 29085 IONIEUWSBRIEF@LS.KULEUVEN.BE (Linux 2.6.32) 12 28918 BEDRIJVENLIJST@LS.KULEUVEN.BE (Linux 2.6.32) 13 28918 BEDRIJVENLIJST2@LS.KULEUVEN.BE (Linux 2.6.32) 14 28827 HALLCOLIBRARY-L@LISTSERV.UGA.EDU (Linux 2.6.32) 15 28337 L-THON-NEWS@LISTS.PSU.EDU (AIX 6.1) 16 27710 RECREATION@LISTSERV.MIAMIOH.EDU (Windows Server 2012 R2 Standard x64 Edition) 17 27412 VOLUPDATE@LISTSERV.UTK.EDU (Solaris 2.10) 18 26418 PARENTS@LISTSERV.TAMU.EDU (Linux 3.0.101) 19 24990 NCHPAD-NEWS@LISTSERV.UAB.EDU (Linux 2.6.32) 20 23789 ISMA@LS.KULEUVEN.BE (Linux 2.6.32)