![[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 926890 JISCMAIL.AC.UK (Windows Server 2019 Standard x64 Edition) 2 562836 LISTSERV.TAMU.EDU (Linux 3.0.101) 3 448936 LISTSERV.LIV.AC.UK (Linux 3.10.0) 4 445335 LISTS.PSU.EDU (Linux 3.10.0) 5 373489 LIST.ETSI.ORG (Windows Server 2016 Datacenter x64 Edition) 6 294086 LISTES.ULAVAL.CA (Linux 3.10.0) 7 289374 LISTSERV.SYR.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 8 253373 LISTSERV.UGA.EDU (Linux 2.6.32) 9 241853 DISCUSSIONS.EQ.EDU.AU (Linux 3.10.0-1160.11.1.el7.x86_64) 10 233014 LISTS.HAWAII.EDU (Linux 2.6.32-754.36.1.el6.x86_64) 11 226742 LISTSERV.ACM.ORG (Windows Server 2012 R2 Datacenter x64 Edition) 12 223946 LISTS.UFL.EDU (Linux 2.6.32) 13 196316 LISTSERV.UCONN.EDU (Windows Server 2012 R2 Standard x64 Edition) 14 195256 LISTSERV.NODAK.EDU (Windows Server 2019 Standard x64 Edition) 15 194068 LSV.UKY.EDU (Windows Server 2019 Datacenter x64 Edition) 16 193324 LISTSERV.REDIRIS.ES (Linux 2.6.32-504.3.3.el6.x86_64) 17 186060 LISTSERV.BUFFALO.EDU (Linux 3.10.0) 18 172541 LISTSERV.UIC.EDU (Linux 2.6.32-504.8.1.el6.x86_64) 19 151995 LIST.UNM.EDU (Linux 3.10.0-1160.6.1.el7.x86_64) 20 143871 LISTSERV.UTORONTO.CA (Linux 3.10.0)
Pos Subscribers Site --- ----------- ---- 1 4877473 LISTS.PSU.EDU (Linux 3.10.0) 2 4470874 LISTES.ULAVAL.CA (Linux 3.10.0) 3 2292766 LS.KULEUVEN.BE (Linux 2.6.32) 4 1750127 LISTSERV.TAU.AC.IL (Linux 2.6.9) 5 1333466 LISTSERV.UTORONTO.CA (Linux 3.10.0) 6 1268260 LISTS.WAYNE.EDU (Linux 2.6.32) 7 1255398 LISTSERV.TAMU.EDU (Linux 3.0.101) 8 1128815 LSV.UKY.EDU (Windows Server 2019 Datacenter x64 Edition) 9 1120733 LIST.MSU.EDU (Linux 3.10.0) 10 1059036 LISTS.UFL.EDU (Linux 2.6.32) 11 972040 LISTSERV.UA.EDU (Linux 4.12.14) 12 946016 LISTS.UMN.EDU (Linux 3.10.0) 13 889815 LISTSERV.ECU.EDU (Windows Server 2016 Standard x64 Edition) 14 867458 LISTSERV.SYR.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 15 855419 LISTSERV.UTA.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 16 836487 LISTSERV.MIAMIOH.EDU (Windows Server 2016 Standard x64 Edition) 17 835576 LISTSERV.BUFFALO.EDU (Linux 3.10.0) 18 784514 LISTSERV.UH.EDU (Linux 3.10.0) 19 700637 LISTSERV.LIV.AC.UK (Linux 3.10.0) 20 688048 LISTSERV.NODAK.EDU (Windows Server 2019 Standard x64 Edition)
Pos Lists Site --- ----- ---- 1 27510 LISTES.ULAVAL.CA (Linux 3.10.0) 2 17010 LISTS.PSU.EDU (Linux 3.10.0) 3 13899 LISTSERV.TAU.AC.IL (Linux 2.6.9) 4 9788 LISTS.CLEMSON.EDU (Linux 2.6.18) 5 9599 LISTS.UFL.EDU (Linux 2.6.32) 6 8079 LISTSERV.TECHNION.AC.IL (Linux 2.6.32) 7 7565 LISTSERV.LIV.AC.UK (Linux 3.10.0) 8 6737 LISTSERV.MIAMIOH.EDU (Windows Server 2016 Standard x64 Edition) 9 5802 LSV.UKY.EDU (Windows Server 2019 Datacenter x64 Edition) 10 5761 LISTSERV.UTORONTO.CA (Linux 3.10.0) 11 5338 LS.KULEUVEN.BE (Linux 2.6.32) 12 5015 LISTSERV.TAMU.EDU (Linux 3.0.101) 13 4869 LISTS.UMN.EDU (Linux 3.10.0) 14 4265 LISTSERV.SYR.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 15 4211 LISTS.QUEENSU.CA (Linux 3.10.0) 16 3776 LISTSERV.BUFFALO.EDU (Linux 3.10.0) 17 3719 LISTSERV.NODAK.EDU (Windows Server 2019 Standard x64 Edition) 18 3367 LIST.UVM.EDU (Linux 2.6.32) 19 3338 LISTSERV.BROWN.EDU (Linux 3.10.0) 20 2727 LISTSERV.KENT.EDU (Windows Server 2012 R2 Standard x64 Edition)
Pos Recipients Site --- ---------- ---- 1 894763 JISCMAIL.AC.UK (Windows Server 2019 Standard x64 Edition) 2 559422 LISTSERV.TAMU.EDU (Linux 3.0.101) 3 441778 LISTS.PSU.EDU (Linux 3.10.0) 4 435651 LISTSERV.LIV.AC.UK (Linux 3.10.0) 5 372887 LIST.ETSI.ORG (Windows Server 2016 Datacenter x64 Edition) 6 293752 LISTES.ULAVAL.CA (Linux 3.10.0) 7 248618 LISTSERV.UGA.EDU (Linux 2.6.32) 8 241602 DISCUSSIONS.EQ.EDU.AU (Linux 3.10.0-1160.11.1.el7.x86_64) 9 231674 LISTS.HAWAII.EDU (Linux 2.6.32-754.36.1.el6.x86_64) 10 222035 LISTS.UFL.EDU (Linux 2.6.32) 11 203372 LISTSERV.SYR.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 12 196084 LISTSERV.UCONN.EDU (Windows Server 2012 R2 Standard x64 Edition) 13 191914 LSV.UKY.EDU (Windows Server 2019 Datacenter x64 Edition) 14 190916 LISTSERV.REDIRIS.ES (Linux 2.6.32-504.3.3.el6.x86_64) 15 185538 LISTSERV.NODAK.EDU (Windows Server 2019 Standard x64 Edition) 16 181520 LISTSERV.BUFFALO.EDU (Linux 3.10.0) 17 172300 LISTSERV.UIC.EDU (Linux 2.6.32-504.8.1.el6.x86_64) 18 151771 LIST.UNM.EDU (Linux 3.10.0-1160.6.1.el7.x86_64) 19 143761 LISTSERV.UTORONTO.CA (Linux 3.10.0) 20 134481 LISTSERV.UA.EDU (Linux 4.12.14)
Pos Subscribers Site --- ----------- ---- 1 54050 AMIS-CNRS-INTERNATIONAL-L@IN2P3.FR (Linux 3.10.0) 2 43374 SAFETYNOTICE@LISTSERV.UC.EDU (Windows Server 2019 Datacenter x64 Edition) 3 41809 OPSWNEWS@LISTSERV.NYSED.GOV (Linux 4.12.14) 4 34587 TCUATHLETICSDIRECTOR@LISTSERV.TCU.EDU (Windows Server 2012 R2 Standard x64 Edition) 5 34000 CMU-BASKETBALL@LS2.CMICH.EDU (Linux 3.10.0) 6 33577 L-SMEAL-REPORT@LISTS.PSU.EDU (Linux 3.10.0) 7 33213 TAU-STU-ACADEMICSEC-STUDENTS@LISTSERV.TAU.AC.IL (Linux 2.6.9) 8 30835 FOCIS_GROUP@LISTS.WAYNE.EDU (Linux 2.6.32) 9 29732 TAU-INNOVTL-ALL-STUDENTS@LISTSERV.TAU.AC.IL (Linux 2.6.9) 10 28918 BEDRIJVENLIJST@LS.KULEUVEN.BE (Linux 2.6.32) 11 28918 BEDRIJVENLIJST2@LS.KULEUVEN.BE (Linux 2.6.32) 12 28302 L-THON-NEWS@LISTS.PSU.EDU (Linux 3.10.0) 13 27707 RECREATION@LISTSERV.MIAMIOH.EDU (Windows Server 2016 Standard x64 Edition) 14 27480 TAU4U@LISTSERV.TAU.AC.IL (Linux 2.6.9) 15 27390 VOLUPDATE@LISTSERV.UTK.EDU (Linux 3.10.0) 16 26418 PARENTS@LISTSERV.TAMU.EDU (Linux 3.0.101) 17 25579 ISMA@LS.KULEUVEN.BE (Linux 2.6.32) 18 24992 NCHPAD-NEWS@LISTSERV.UAB.EDU (Linux 3.10.0) 19 24304 EXCEL@LISTSERV.UTA.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 20 23331 ECF-MIWD@NYED.USCOURTS.GOV (Linux 3.10.0)