![[LISTSERV - the mailing list management classic]](/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 627839 JISCMAIL.AC.UK (Windows Server 2019 Standard x64 Edition) 2 237475 LISTSERV.LIV.AC.UK (Linux 3.10.0) 3 207681 LISTS.PSU.EDU (Linux 3.10.0) 4 204021 LISTSERV.ACM.ORG (Windows Server 2016 Datacenter x64 Edition) 5 174325 DISCUSSIONS.EQ.EDU.AU (Linux 3.10.0-1160.59.1.el7.x86_64) 6 145715 LISTSERV.REDIRIS.ES (Linux 3.10.0-1062.9.1.el7.x86_64) 7 111673 LISTSERV.UGA.EDU (Windows Server 2016 Datacenter x64 Edition) 8 108419 LISTSERV.TDBANK.CA (Windows Server 2016 Datacenter x64 Edition) 9 105744 LSV.UKY.EDU (Windows Server 2019 Datacenter x64 Edition) 10 103673 LISTSERV.UIC.EDU (Linux 2.6.32-504.8.1.el6.x86_64) 11 100169 LISTS.HAWAII.EDU (Linux 3.10.0-1160.71.1.el7.x86_64) 12 99679 LISTSERV.UCONN.EDU (Windows Server 2019 Datacenter x64 Edition) 13 96071 LISTSERV.SYR.EDU (Windows Server 2019 Standard x64 Edition) 14 93077 LISTS.UFL.EDU (Linux 2.6.32) 15 85553 LISTSERV.NODAK.EDU (Windows Server 2019 Standard x64 Edition) 16 82732 LISTS.PORTSIDE.ORG (Linux 4.9.0-17-amd64) 17 81740 LISTSERV.ICORS.ORG (Windows Server 2016 Datacenter x64 Edition) 18 79702 LIST.UVM.EDU (Linux 2.6.32) 19 78965 LISTS.ROCHESTER.EDU (Windows Server 2012 R2 Standard x64 Edition) 20 77085 LISTSERV.BROWN.EDU (Linux 3.10.0)
Pos Subscribers Site --- ----------- ---- 1 5173358 LISTS.PSU.EDU (Linux 3.10.0) 2 4572845 LISTES.ULAVAL.CA (Linux 3.10.0) 3 1833650 LISTSERV.UGA.EDU (Windows Server 2016 Datacenter x64 Edition) 4 1777535 LISTSERV.TAU.AC.IL (Linux 2.6.9) 5 1380842 LISTSERV.UTORONTO.CA (Linux 3.10.0) 6 1227154 LISTSERV.UA.EDU (Linux 4.12.14) 7 1194124 LISTSERV.TAMU.EDU (Linux 3.0.101) 8 1059036 LISTS.UFL.EDU (Linux 2.6.32) 9 1041503 LSV.UKY.EDU (Windows Server 2019 Datacenter x64 Edition) 10 993965 LISTS.WAYNE.EDU (Linux 2.6.32) 11 937756 LISTS.UMN.EDU (Linux 3.10.0) 12 911357 LIST.MSU.EDU (Linux 3.10.0) 13 853488 LISTSERV.UTA.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 14 825760 LISTSERV.BUFFALO.EDU (Linux 3.10.0) 15 810248 LISTSERV.SYR.EDU (Windows Server 2019 Standard x64 Edition) 16 808214 LISTSERV.UH.EDU (Linux 3.10.0) 17 797580 LISTSERV.ECU.EDU (Windows Server 2016 Standard x64 Edition) 18 775358 LISTSERV.MIAMIOH.EDU (Windows Server 2016 Standard x64 Edition) 19 708380 LISTS.QUEENSU.CA (Linux 3.10.0) 20 684363 LISTSERV.LIV.AC.UK (Linux 3.10.0)
Pos Lists Site --- ----- ---- 1 28183 LISTES.ULAVAL.CA (Linux 3.10.0) 2 16635 LISTS.PSU.EDU (Linux 3.10.0) 3 14174 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 7162 LISTSERV.LIV.AC.UK (Linux 3.10.0) 8 6771 LISTSERV.MIAMIOH.EDU (Windows Server 2016 Standard x64 Edition) 9 6344 LISTSERV.UTORONTO.CA (Linux 3.10.0) 10 5339 LISTSERV.UGA.EDU (Windows Server 2016 Datacenter x64 Edition) 11 4987 LISTSERV.TAMU.EDU (Linux 3.0.101) 12 4817 LISTS.UMN.EDU (Linux 3.10.0) 13 4466 LISTSERV.SYR.EDU (Windows Server 2019 Standard x64 Edition) 14 4274 LSV.UKY.EDU (Windows Server 2019 Datacenter x64 Edition) 15 3865 LISTSERV.BUFFALO.EDU (Linux 3.10.0) 16 3850 LISTS.QUEENSU.CA (Linux 3.10.0) 17 3540 LIST.UVM.EDU (Linux 2.6.32) 18 3487 LISTSERV.BROWN.EDU (Linux 3.10.0) 19 3308 LISTSERV.NODAK.EDU (Windows Server 2019 Standard x64 Edition) 20 2797 LISTSERV.KENT.EDU (Windows Server 2012 R2 Standard x64 Edition)
Pos Recipients Site --- ---------- ---- 1 600197 JISCMAIL.AC.UK (Windows Server 2019 Standard x64 Edition) 2 231146 LISTSERV.LIV.AC.UK (Linux 3.10.0) 3 204855 LISTS.PSU.EDU (Linux 3.10.0) 4 174173 DISCUSSIONS.EQ.EDU.AU (Linux 3.10.0-1160.59.1.el7.x86_64) 5 143930 LISTSERV.REDIRIS.ES (Linux 3.10.0-1062.9.1.el7.x86_64) 6 109761 LISTSERV.UGA.EDU (Windows Server 2016 Datacenter x64 Edition) 7 103759 LSV.UKY.EDU (Windows Server 2019 Datacenter x64 Edition) 8 103518 LISTSERV.UIC.EDU (Linux 2.6.32-504.8.1.el6.x86_64) 9 99850 LISTS.HAWAII.EDU (Linux 3.10.0-1160.71.1.el7.x86_64) 10 99284 LISTSERV.UCONN.EDU (Windows Server 2019 Datacenter x64 Edition) 11 91705 LISTS.UFL.EDU (Linux 2.6.32) 12 83054 LISTSERV.NODAK.EDU (Windows Server 2019 Standard x64 Edition) 13 82713 LISTS.PORTSIDE.ORG (Linux 4.9.0-17-amd64) 14 80310 LISTSERV.ICORS.ORG (Windows Server 2016 Datacenter x64 Edition) 15 78286 LIST.UVM.EDU (Linux 2.6.32) 16 75239 LISTSERV.SYR.EDU (Windows Server 2019 Standard x64 Edition) 17 72507 L.GOP.COM (Windows Server 2016 Standard x64 Edition) 18 71888 LISTSERV.DARTMOUTH.EDU (Windows Server 2016 Datacenter x64 Edition) 19 71271 LIST.MSU.EDU (Linux 3.10.0) 20 70197 LISTSERV.BUFFALO.EDU (Linux 3.10.0)
Pos Subscribers Site --- ----------- ---- 1 54050 AMIS-CNRS-INTERNATIONAL-L@IN2P3.FR (Linux 3.10.0) 2 48016 SAFETYNOTICE@LISTSERV.UC.EDU (Windows Server 2019 Datacenter x64 Edition) 3 41822 OPSWNEWS@LISTSERV.NYSED.GOV (Linux 4.12.14) 4 39327 SUCCESS@LISTSERV.UGA.EDU (Windows Server 2016 Datacenter x64 Edition) 5 34587 TCUATHLETICSDIRECTOR@LISTSERV.TCU.EDU (Windows Server 2012 R2 Standard x64 Edition) 6 33104 CMU-BASKETBALL@LS2.CMICH.EDU (Linux 3.10.0) 7 31621 TAU-STU-ACADEMICSEC-STUDENTS@LISTSERV.TAU.AC.IL (Linux 2.6.9) 8 30206 UG2021FALL@LISTSERV.UGA.EDU (Windows Server 2016 Datacenter x64 Edition) 9 28887 TAU-INNOVTL-ALL-STUDENTS@LISTSERV.TAU.AC.IL (Linux 2.6.9) 10 28264 L-THON-NEWS@LISTS.PSU.EDU (Linux 3.10.0) 11 28250 HALLCOLIBRARY-L@LISTSERV.UGA.EDU (Windows Server 2016 Datacenter x64 Edition) 12 27705 RECREATION@LISTSERV.MIAMIOH.EDU (Windows Server 2016 Standard x64 Edition) 13 27479 TAU4U@LISTSERV.TAU.AC.IL (Linux 2.6.9) 14 27375 VOLUPDATE@LISTSERV.UTK.EDU (Linux 3.10.0) 15 27347 UTENNSRP@LISTSERV.UTK.EDU (Linux 3.10.0) 16 26422 PARENTS@LISTSERV.TAMU.EDU (Linux 3.0.101) 17 25027 ECF-MIWD@NYED.USCOURTS.GOV (Linux 3.10.0) 18 24992 NCHPAD-NEWS@LISTSERV.UAB.EDU (Linux 3.10.0) 19 24288 EXCEL@LISTSERV.UTA.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 20 22770 STUDENT-TRAVEL-SURVEY-L@LISTSERV.OKSTATE.EDU (Windows Server 2012 Datacenter x64 Edition)