![[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 767011 JISCMAIL.AC.UK (Windows Server 2019 Standard x64 Edition) 2 365185 LISTSERV.LIV.AC.UK (Linux 3.10.0) 3 331430 LIST.ETSI.ORG (Windows Server 2016 Datacenter x64 Edition) 4 328448 LISTS.PSU.EDU (Linux 3.10.0) 5 275559 LISTES.ULAVAL.CA (Linux 3.10.0) 6 241634 LISTS.HAWAII.EDU (Linux 3.10.0-1160.49.1.el7.x86_64) 7 238063 LISTSERV.ACM.ORG (Windows Server 2016 Datacenter x64 Edition) 8 213231 LISTSERV.UGA.EDU (Windows Server 2016 Datacenter x64 Edition) 9 183066 LISTSERV.REDIRIS.ES (Linux 3.10.0-1062.9.1.el7.x86_64) 10 178200 LISTSERV.UIC.EDU (Linux 2.6.32-504.8.1.el6.x86_64) 11 170315 LISTSERV.SYR.EDU (Windows Server 2019 Standard x64 Edition) 12 169240 LISTS.UFL.EDU (Linux 2.6.32) 13 166907 LISTSERV.NODAK.EDU (Windows Server 2019 Standard x64 Edition) 14 159186 LISTSERV.TDBANK.CA (Windows Server 2016 Datacenter x64 Edition) 15 153979 LISTSERV.UA.EDU (Linux 4.12.14) 16 148336 LISTSERV.UCONN.EDU (Windows Server 2019 Datacenter x64 Edition) 17 143043 LSV.UKY.EDU (Windows Server 2019 Datacenter x64 Edition) 18 117069 LISTS.ROCHESTER.EDU (Windows Server 2012 R2 Standard x64 Edition) 19 116536 LISTSERV.UTORONTO.CA (Linux 3.10.0) 20 111439 LISTSERV.ICORS.ORG (Windows Server 2016 Datacenter x64 Edition)
Pos Subscribers Site --- ----------- ---- 1 5434933 LISTS.PSU.EDU (Linux 3.10.0) 2 4682970 LISTES.ULAVAL.CA (Linux 3.10.0) 3 1777535 LISTSERV.TAU.AC.IL (Linux 2.6.9) 4 1716943 LISTSERV.UGA.EDU (Windows Server 2016 Datacenter x64 Edition) 5 1506168 LISTSERV.UTORONTO.CA (Linux 3.10.0) 6 1247986 LISTSERV.TAMU.EDU (Linux 3.0.101) 7 1170614 LISTSERV.UA.EDU (Linux 4.12.14) 8 1059036 LISTS.UFL.EDU (Linux 2.6.32) 9 1032750 LSV.UKY.EDU (Windows Server 2019 Datacenter x64 Edition) 10 1026065 LISTS.WAYNE.EDU (Linux 2.6.32) 11 992106 LIST.MSU.EDU (Linux 3.10.0) 12 925150 LISTS.UMN.EDU (Linux 3.10.0) 13 862521 LISTSERV.SYR.EDU (Windows Server 2019 Standard x64 Edition) 14 853488 LISTSERV.UTA.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 15 850148 LISTSERV.BUFFALO.EDU (Linux 3.10.0) 16 837910 LISTSERV.ECU.EDU (Windows Server 2016 Standard x64 Edition) 17 833150 LISTSERV.MIAMIOH.EDU (Windows Server 2016 Standard x64 Edition) 18 814345 LISTSERV.UH.EDU (Linux 3.10.0) 19 700231 LISTSERV.LIV.AC.UK (Linux 3.10.0) 20 682447 LISTS.QUEENSU.CA (Linux 3.10.0)
Pos Lists Site --- ----- ---- 1 27887 LISTES.ULAVAL.CA (Linux 3.10.0) 2 16528 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 7136 LISTSERV.LIV.AC.UK (Linux 3.10.0) 8 6763 LISTSERV.MIAMIOH.EDU (Windows Server 2016 Standard x64 Edition) 9 6167 LISTSERV.UTORONTO.CA (Linux 3.10.0) 10 5186 LISTSERV.UGA.EDU (Windows Server 2016 Datacenter x64 Edition) 11 4987 LISTSERV.TAMU.EDU (Linux 3.0.101) 12 4809 LISTS.UMN.EDU (Linux 3.10.0) 13 4415 LISTSERV.SYR.EDU (Windows Server 2019 Standard x64 Edition) 14 4239 LSV.UKY.EDU (Windows Server 2019 Datacenter x64 Edition) 15 3818 LISTSERV.BUFFALO.EDU (Linux 3.10.0) 16 3771 LISTS.QUEENSU.CA (Linux 3.10.0) 17 3430 LISTSERV.BROWN.EDU (Linux 3.10.0) 18 3407 LIST.UVM.EDU (Linux 2.6.32) 19 3290 LISTSERV.NODAK.EDU (Windows Server 2019 Standard x64 Edition) 20 2774 LISTSERV.KENT.EDU (Windows Server 2012 R2 Standard x64 Edition)
Pos Recipients Site --- ---------- ---- 1 737486 JISCMAIL.AC.UK (Windows Server 2019 Standard x64 Edition) 2 357019 LISTSERV.LIV.AC.UK (Linux 3.10.0) 3 330944 LIST.ETSI.ORG (Windows Server 2016 Datacenter x64 Edition) 4 325392 LISTS.PSU.EDU (Linux 3.10.0) 5 275366 LISTES.ULAVAL.CA (Linux 3.10.0) 6 239062 LISTS.HAWAII.EDU (Linux 3.10.0-1160.49.1.el7.x86_64) 7 209047 LISTSERV.UGA.EDU (Windows Server 2016 Datacenter x64 Edition) 8 181089 LISTSERV.REDIRIS.ES (Linux 3.10.0-1062.9.1.el7.x86_64) 9 177999 LISTSERV.UIC.EDU (Linux 2.6.32-504.8.1.el6.x86_64) 10 168159 LISTS.UFL.EDU (Linux 2.6.32) 11 163519 LISTSERV.NODAK.EDU (Windows Server 2019 Standard x64 Edition) 12 150944 LISTSERV.UA.EDU (Linux 4.12.14) 13 148121 LISTSERV.UCONN.EDU (Windows Server 2019 Datacenter x64 Edition) 14 140903 LSV.UKY.EDU (Windows Server 2019 Datacenter x64 Edition) 15 119399 LISTSERV.SYR.EDU (Windows Server 2019 Standard x64 Edition) 16 116618 LISTSERV.UTORONTO.CA (Linux 3.10.0) 17 109731 LISTSERV.ICORS.ORG (Windows Server 2016 Datacenter x64 Edition) 18 106577 DISCUSSIONS.EQ.EDU.AU (Linux 3.10.0-1160.45.1.el7.x86_64) 19 105706 LISTSERV.DARTMOUTH.EDU (Windows Server 2016 Datacenter x64 Edition) 20 102602 LISTSERV.AAP.ORG (Windows Server 2012 R2 Standard x64 Edition)
Pos Subscribers Site --- ----------- ---- 1 54050 AMIS-CNRS-INTERNATIONAL-L@IN2P3.FR (Linux 3.10.0) 2 41927 SAFETYNOTICE@LISTSERV.UC.EDU (Windows Server 2019 Datacenter x64 Edition) 3 41816 OPSWNEWS@LISTSERV.NYSED.GOV (Linux 4.12.14) 4 39350 SUCCESS@LISTSERV.UGA.EDU (Windows Server 2016 Datacenter x64 Edition) 5 34587 TCUATHLETICSDIRECTOR@LISTSERV.TCU.EDU (Windows Server 2012 R2 Standard x64 Edition) 6 33786 CMU-BASKETBALL@LS2.CMICH.EDU (Linux 3.10.0) 7 31621 TAU-STU-ACADEMICSEC-STUDENTS@LISTSERV.TAU.AC.IL (Linux 2.6.9) 8 30225 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 28276 L-THON-NEWS@LISTS.PSU.EDU (Linux 3.10.0) 11 27706 RECREATION@LISTSERV.MIAMIOH.EDU (Windows Server 2016 Standard x64 Edition) 12 27582 HALLCOLIBRARY-L@LISTSERV.UGA.EDU (Windows Server 2016 Datacenter x64 Edition) 13 27479 TAU4U@LISTSERV.TAU.AC.IL (Linux 2.6.9) 14 27380 VOLUPDATE@LISTSERV.UTK.EDU (Linux 3.10.0) 15 27348 UTENNSRP@LISTSERV.UTK.EDU (Linux 3.10.0) 16 26421 PARENTS@LISTSERV.TAMU.EDU (Linux 3.0.101) 17 24992 NCHPAD-NEWS@LISTSERV.UAB.EDU (Linux 3.10.0) 18 24633 ECF-MIWD@NYED.USCOURTS.GOV (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)