![[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 844365 JISCMAIL.AC.UK (Windows Server 2008 R2 Enterprise x64 Edition) 2 700343 LISTSERV.TAMU.EDU (Linux 3.0.101) 3 499940 LISTS.PSU.EDU (AIX 6.1) 4 313753 LISTSERV.LIV.AC.UK (Linux 2.6.32) 5 309655 LSERV.CARDSYS.AT (Linux 4.4.98-5-pve) 6 266518 LSV.UKY.EDU (Windows Server 2012 R2 Datacenter x64 Edition) 7 260573 LISTSERV.BUFFALO.EDU (Solaris 2.11) 8 258733 LISTSERV.SYR.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 9 257594 LISTSERV.UGA.EDU (Linux 2.6.32) 10 257221 LISTES.ULAVAL.CA (Linux 2.6.18) 11 245021 LISTSERV.UMD.EDU (SunOS 5.10) 12 228614 LISTS.UFL.EDU (Linux 2.6.18) 13 220819 DISCUSSIONS.EQ.EDU.AU (Linux 2.6.18-404.el5) 14 214974 DIGITAL.ANNEXBUSINESSMEDIA.COM (Linux 3.13.0-32-generic) 15 213337 LISTSERV.DARTMOUTH.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 16 204032 LISTSERV.REDIRIS.ES (Linux 2.6.32-504.3.3.el6.x86_64) 17 198391 LISTS.UCDENVER.EDU (Windows Server 2012 R2 Standard x64 Edition) 18 197647 LISTSERV.ACM.ORG (Windows Server 2012 R2 Datacenter x64 Edition) 19 193623 LISTS.HAWAII.EDU (Linux 2.6.32-696.16.1.el6.x86_64) 20 184018 LIST.ETSI.ORG (Windows Server 2016 Datacenter x64 Edition + LSMTP V1.1b)
Pos Subscribers Site --- ----------- ---- 1 5292619 LISTS.PSU.EDU (AIX 6.1) 2 3639778 LISTES.ULAVAL.CA (Linux 2.6.18) 3 1964333 LS.KULEUVEN.BE (Linux 2.6.32) 4 1568319 LISTS.WAYNE.EDU (Linux 2.6.32) 5 1417191 LSV.UKY.EDU (Windows Server 2012 R2 Datacenter x64 Edition) 6 1348993 LISTSERV.UGA.EDU (Linux 2.6.32) 7 1348520 LISTSERV.TAMU.EDU (Linux 3.0.101) 8 1338133 LISTSERV.TAU.AC.IL (Linux 2.6.9) 9 1224165 LISTSERV.UTORONTO.CA (Linux 2.6.18) 10 1059036 LISTS.UFL.EDU (Linux 2.6.18) 11 1041547 LISTSERV.BUFFALO.EDU (Solaris 2.11) 12 997834 LISTS.UMN.EDU (Linux 2.6.32) 13 944029 LIST.MSU.EDU (Linux 3.10.0) 14 819993 LISTSERV.UH.EDU (Linux 3.10.0) 15 818258 CUVMC.AIS.COLUMBIA.EDU (VM/SP 4.0) 16 812761 LISTSERV.SYR.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 17 780768 LISTSERV.MIAMIOH.EDU (Windows Server 2012 R2 Standard x64 Edition) 18 766370 LISTSERV.NODAK.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 19 743699 LISTSERV.UA.EDU (Linux 3.0.101) 20 733995 LISTSERV.ECU.EDU (Windows Server 2008 R2 Enterprise x64 Edition)
Pos Lists Site --- ----- ---- 1 27038 LISTES.ULAVAL.CA (Linux 2.6.18) 2 16863 LISTS.PSU.EDU (AIX 6.1) 3 14050 LSV.UKY.EDU (Windows Server 2012 R2 Datacenter x64 Edition) 4 13323 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 7938 LISTSERV.TECHNION.AC.IL (Linux 2.6.32) 8 6995 MARIST (VM/SP 2.0) 9 6816 LISTSERV.TAMU.EDU (Linux 3.0.101) 10 6594 LISTSERV.MIAMIOH.EDU (Windows Server 2012 R2 Standard x64 Edition) 11 6289 LISTSERV.LIV.AC.UK (Linux 2.6.32) 12 5716 LISTSERV.MILLERSVILLE.EDU (Linux 2.6.32) 13 5483 LISTS.UMN.EDU (Linux 2.6.32) 14 5264 LISTSERV.UGA.EDU (Linux 2.6.32) 15 4403 LISTSERV.NODAK.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 16 4333 LISTSERV.UTORONTO.CA (Linux 2.6.18) 17 4109 LS.KULEUVEN.BE (Linux 2.6.32) 18 3879 LISTS.QUEENSU.CA (Solaris 2.10) 19 3752 LISTSERV.SYR.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 20 3576 YORKU.CA (Linux 2.6.32)
Pos Recipients Site --- ---------- ---- 1 815095 JISCMAIL.AC.UK (Windows Server 2008 R2 Enterprise x64 Edition) 2 698943 LISTSERV.TAMU.EDU (Linux 3.0.101) 3 495085 LISTS.PSU.EDU (AIX 6.1) 4 300011 LISTSERV.LIV.AC.UK (Linux 2.6.32) 5 263706 LSV.UKY.EDU (Windows Server 2012 R2 Datacenter x64 Edition) 6 257044 LISTES.ULAVAL.CA (Linux 2.6.18) 7 255787 LISTSERV.BUFFALO.EDU (Solaris 2.11) 8 251904 LISTSERV.UGA.EDU (Linux 2.6.32) 9 226170 LISTS.UFL.EDU (Linux 2.6.18) 10 222189 LISTSERV.UMD.EDU (SunOS 5.10) 11 220623 DISCUSSIONS.EQ.EDU.AU (Linux 2.6.18-404.el5) 12 219120 LISTSERV.SYR.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 13 208204 LISTSERV.DARTMOUTH.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 14 201048 LISTSERV.REDIRIS.ES (Linux 2.6.32-504.3.3.el6.x86_64) 15 198334 LISTS.UCDENVER.EDU (Windows Server 2012 R2 Standard x64 Edition) 16 192211 LISTS.HAWAII.EDU (Linux 2.6.32-696.16.1.el6.x86_64) 17 183454 LIST.ETSI.ORG (Windows Server 2016 Datacenter x64 Edition + LSMTP V1.1b) 18 174697 LIST.UVM.EDU (Linux 2.6.32) 19 171247 LISTSERV.UCONN.EDU (Windows Server 2012 R2 Standard x64 Edition) 20 168646 LIST.MSU.EDU (Linux 3.10.0)
Pos Subscribers Site --- ----------- ---- 1 300656 COMPUTING@LIST.MSU.EDU (Linux 3.10.0) 2 62441 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 39091 CAREERCENTERUPDATE@LISTSERV.UGA.EDU (Linux 2.6.32) 6 38348 SAFETYNOTICE@LISTSERV.UC.EDU (Windows Server 2012 R2 Datacenter x64 Edition) 7 35788 CMU-BASKETBALL@LS2.CMICH.EDU (Linux 3.10.0) 8 34587 TCUATHLETICSDIRECTOR@LISTSERV.TCU.EDU (Windows Server 2012 R2 Standard x64 Edition) 9 33611 L-SMEAL-REPORT@LISTS.PSU.EDU (AIX 6.1) 10 30848 FOCIS_GROUP@LISTS.WAYNE.EDU (Linux 2.6.32) 11 28918 BEDRIJVENLIJST@LS.KULEUVEN.BE (Linux 2.6.32) 12 28918 BEDRIJVENLIJST2@LS.KULEUVEN.BE (Linux 2.6.32) 13 28908 HALLCOLIBRARY-L@LISTSERV.UGA.EDU (Linux 2.6.32) 14 28339 L-THON-NEWS@LISTS.PSU.EDU (AIX 6.1) 15 27710 RECREATION@LISTSERV.MIAMIOH.EDU (Windows Server 2012 R2 Standard x64 Edition) 16 27413 VOLUPDATE@LISTSERV.UTK.EDU (Solaris 2.10) 17 26419 PARENTS@LISTSERV.TAMU.EDU (Linux 3.0.101) 18 24990 NCHPAD-NEWS@LISTSERV.UAB.EDU (Linux 2.6.32) 19 23786 ISMA@LS.KULEUVEN.BE (Linux 2.6.32) 20 23329 ECF-EDNY@NYED.USCOURTS.GOV (Linux 2.6.32)