![[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 874251 JISCMAIL.AC.UK (Windows Server 2008 R2 Enterprise x64 Edition) 2 731010 LISTSERV.TAMU.EDU (Linux 3.0.101) 3 365186 LISTSERV.LIV.AC.UK (Linux 2.6.32) 4 363304 LISTS.PSU.EDU (AIX 6.1) 5 293631 LISTES.ULAVAL.CA (Linux 3.10.0) 6 243015 LISTSERV.UGA.EDU (Linux 2.6.32) 7 226780 LISTS.HAWAII.EDU (Linux 2.6.32-754.25.1.el6.x86_64) 8 205492 DISCUSSIONS.EQ.EDU.AU (Linux 3.10.0-957.12.2.el7.x86_64) 9 204121 LISTSERV.BUFFALO.EDU (Linux 3.10.0) 10 201433 LISTSERV.SYR.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 11 186827 LSV.UKY.EDU (Windows Server 2012 R2 Datacenter x64 Edition) 12 186715 LISTS.UFL.EDU (Linux 2.6.32) 13 158430 LISTSERV.REDIRIS.ES (Linux 2.6.32-504.3.3.el6.x86_64) 14 145512 LISTSERV.UIC.EDU (Linux 2.6.32-504.8.1.el6.x86_64) 15 144133 LISTSERV.DARTMOUTH.EDU (Windows Server 2016 Datacenter x64 Edition) 16 138325 LISTSERV.NODAK.EDU (Windows Server 2019 Standard x64 Edition) 17 137256 LISTSERV.TDBANK.CA (Windows Server 2012 R2 Datacenter x64 Edition) 18 135197 LISTSERV.ICORS.ORG (Windows Server 2012 R2 Datacenter x64 Edition) 19 134987 LISTSERV.UCONN.EDU (Windows Server 2012 R2 Standard x64 Edition) 20 132297 LISTSERV.ACM.ORG (Windows Server 2012 R2 Datacenter x64 Edition)
Pos Subscribers Site --- ----------- ---- 1 5080814 LISTS.PSU.EDU (AIX 6.1) 2 3924277 LISTES.ULAVAL.CA (Linux 3.10.0) 3 2253592 LS.KULEUVEN.BE (Linux 2.6.32) 4 1498481 LISTSERV.UGA.EDU (Linux 2.6.32) 5 1398745 LISTSERV.TAU.AC.IL (Linux 2.6.9) 6 1282581 LISTSERV.UTORONTO.CA (Linux 3.10.0) 7 1274051 LISTSERV.TAMU.EDU (Linux 3.0.101) 8 1220731 LISTS.WAYNE.EDU (Linux 2.6.32) 9 1097981 LSV.UKY.EDU (Windows Server 2012 R2 Datacenter x64 Edition) 10 1059036 LISTS.UFL.EDU (Linux 2.6.32) 11 982099 LISTS.UMN.EDU (Linux 3.10.0) 12 944029 LIST.MSU.EDU (Linux 3.10.0) 13 869395 LISTSERV.ECU.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 14 852882 LISTSERV.BUFFALO.EDU (Linux 3.10.0) 15 835364 LISTSERV.MIAMIOH.EDU (Windows Server 2016 Standard x64 Edition) 16 831565 LISTSERV.SYR.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 17 818258 CUVMC.AIS.COLUMBIA.EDU (VM/SP 4.0) 18 802624 LISTSERV.UA.EDU (Linux 4.12.14) 19 785105 LISTSERV.UH.EDU (Linux 3.10.0) 20 742830 LISTSERV.UC.EDU (Windows Server 2012 R2 Datacenter x64 Edition)
Pos Lists Site --- ----- ---- 1 27669 LISTES.ULAVAL.CA (Linux 3.10.0) 2 16540 LISTS.PSU.EDU (AIX 6.1) 3 12853 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 7861 MARIST (VM/SP 2.0) 8 7238 LISTSERV.LIV.AC.UK (Linux 2.6.32) 9 6707 LISTSERV.MIAMIOH.EDU (Windows Server 2016 Standard x64 Edition) 10 6164 LISTSERV.UGA.EDU (Linux 2.6.32) 11 5910 LSV.UKY.EDU (Windows Server 2012 R2 Datacenter x64 Edition) 12 5467 LISTS.UMN.EDU (Linux 3.10.0) 13 5048 LISTSERV.TAMU.EDU (Linux 3.0.101) 14 4947 LS.KULEUVEN.BE (Linux 2.6.32) 15 4372 LISTSERV.UTORONTO.CA (Linux 3.10.0) 16 4166 LISTSERV.NODAK.EDU (Windows Server 2019 Standard x64 Edition) 17 4082 LISTSERV.SYR.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 18 4009 LISTSERV.MILLERSVILLE.EDU (Linux 2.6.32) 19 3998 LISTS.QUEENSU.CA (Linux 3.10.0) 20 3582 LISTSERV.BUFFALO.EDU (Linux 3.10.0)
Pos Recipients Site --- ---------- ---- 1 842224 JISCMAIL.AC.UK (Windows Server 2008 R2 Enterprise x64 Edition) 2 730138 LISTSERV.TAMU.EDU (Linux 3.0.101) 3 359117 LISTS.PSU.EDU (AIX 6.1) 4 353777 LISTSERV.LIV.AC.UK (Linux 2.6.32) 5 293439 LISTES.ULAVAL.CA (Linux 3.10.0) 6 238242 LISTSERV.UGA.EDU (Linux 2.6.32) 7 226342 LISTS.HAWAII.EDU (Linux 2.6.32-754.25.1.el6.x86_64) 8 205306 DISCUSSIONS.EQ.EDU.AU (Linux 3.10.0-957.12.2.el7.x86_64) 9 199858 LISTSERV.BUFFALO.EDU (Linux 3.10.0) 10 185163 LISTS.UFL.EDU (Linux 2.6.32) 11 183969 LSV.UKY.EDU (Windows Server 2012 R2 Datacenter x64 Edition) 12 165364 LISTSERV.SYR.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 13 155799 LISTSERV.REDIRIS.ES (Linux 2.6.32-504.3.3.el6.x86_64) 14 145252 LISTSERV.UIC.EDU (Linux 2.6.32-504.8.1.el6.x86_64) 15 141575 LISTSERV.DARTMOUTH.EDU (Windows Server 2016 Datacenter x64 Edition) 16 132996 LISTSERV.ICORS.ORG (Windows Server 2012 R2 Datacenter x64 Edition) 17 132785 LISTSERV.UCONN.EDU (Windows Server 2012 R2 Standard x64 Edition) 18 130684 LISTSERV.NODAK.EDU (Windows Server 2019 Standard x64 Edition) 19 124074 LIST.ETSI.ORG (Windows Server 2016 Datacenter x64 Edition) 20 115478 LIST.UVM.EDU (Linux 2.6.32)
Pos Subscribers Site --- ----------- ---- 1 300656 COMPUTING@LIST.MSU.EDU (Linux 3.10.0) 2 59377 CAREERCENTERUPDATE@LISTSERV.UGA.EDU (Linux 2.6.32) 3 54050 AMIS-CNRS-INTERNATIONAL-L@IN2P3.FR (Linux 3.10.0) 4 43988 SAFETYNOTICE@LISTSERV.UC.EDU (Windows Server 2012 R2 Datacenter x64 Edition) 5 41763 OPSWNEWS@LISTSERV.NYSED.GOV (Linux 4.12.14) 6 36586 CMU-BASKETBALL@LS2.CMICH.EDU (Linux 3.10.0) 7 34587 TCUATHLETICSDIRECTOR@LISTSERV.TCU.EDU (Windows Server 2012 R2 Standard x64 Edition) 8 33598 L-SMEAL-REPORT@LISTS.PSU.EDU (AIX 6.1) 9 30835 FOCIS_GROUP@LISTS.WAYNE.EDU (Linux 2.6.32) 10 28918 BEDRIJVENLIJST@LS.KULEUVEN.BE (Linux 2.6.32) 11 28918 BEDRIJVENLIJST2@LS.KULEUVEN.BE (Linux 2.6.32) 12 28310 L-THON-NEWS@LISTS.PSU.EDU (AIX 6.1) 13 28128 HALLCOLIBRARY-L@LISTSERV.UGA.EDU (Linux 2.6.32) 14 27709 RECREATION@LISTSERV.MIAMIOH.EDU (Windows Server 2016 Standard x64 Edition) 15 27399 VOLUPDATE@LISTSERV.UTK.EDU (Solaris 2.10) 16 26419 PARENTS@LISTSERV.TAMU.EDU (Linux 3.0.101) 17 25008 2019-STEM-EVENT-L@LISTSERV.OKSTATE.EDU (Windows Server 2012 Datacenter x64 Edition) 18 24992 NCHPAD-NEWS@LISTSERV.UAB.EDU (Linux 3.10.0) 19 24688 ISMA@LS.KULEUVEN.BE (Linux 2.6.32) 20 24438 EXCEL@LISTSERV.UTA.EDU (Windows Server 2008 R2 Enterprise x64 Edition)