![[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 645126 JISCMAIL.AC.UK (Windows Server 2008 R2 Enterprise x64 Edition) 2 339837 LISTS.PSU.EDU (AIX 6.1) 3 272167 LIST.ETSI.ORG (Windows Server 2016 Datacenter x64 Edition) 4 265114 LISTSERV.LIV.AC.UK (Linux 2.6.32) 5 206891 LISTSERV.TAMU.EDU (Linux 3.0.101) 6 189847 LISTSERV.ACM.ORG (Windows Server 2012 R2 Datacenter x64 Edition) 7 179081 LISTSERV.REDIRIS.ES (Linux 2.6.32-504.3.3.el6.x86_64) 8 169819 LISTS.HAWAII.EDU (Linux 2.6.32-754.24.3.el6.x86_64) 9 167051 LISTSERV.SYR.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 10 163561 LISTES.ULAVAL.CA (Linux 3.10.0) 11 158975 LISTSERV.UGA.EDU (Linux 2.6.32) 12 155408 LSV.UKY.EDU (Windows Server 2012 R2 Datacenter x64 Edition) 13 147491 CFSLIST.SA.GOV.AU (Windows Server 2012 R2 Datacenter x64 Edition) 14 144432 LISTSERV.BUFFALO.EDU (Linux 3.10.0) 15 141045 LISTSERV.NODAK.EDU (Windows Server 2019 Standard x64 Edition) 16 131478 LISTSERV.UCONN.EDU (Windows Server 2012 R2 Standard x64 Edition) 17 130652 LISTS.UFL.EDU (Linux 2.6.32) 18 123208 DISCUSSIONS.EQ.EDU.AU (Linux 3.10.0-957.12.2.el7.x86_64) 19 114138 LISTSERV.UIC.EDU (Linux 2.6.32-504.8.1.el6.x86_64) 20 111150 LISTSERV.AAP.ORG (Windows Server 2012 R2 Standard x64 Edition)
Pos Subscribers Site --- ----------- ---- 1 5084829 LISTS.PSU.EDU (AIX 6.1) 2 4697881 LISTES.ULAVAL.CA (Linux 3.10.0) 3 2204480 LS.KULEUVEN.BE (Linux 2.6.32) 4 1487432 LISTSERV.UGA.EDU (Linux 2.6.32) 5 1401232 LISTSERV.TAU.AC.IL (Linux 2.6.9) 6 1282581 LISTSERV.UTORONTO.CA (Linux 3.10.0) 7 1274757 LISTSERV.TAMU.EDU (Linux 3.0.101) 8 1202465 LISTS.WAYNE.EDU (Linux 2.6.32) 9 1107182 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 865792 LISTSERV.ECU.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 14 839836 LISTSERV.UA.EDU (Linux 4.12.14) 15 831297 LISTSERV.BUFFALO.EDU (Linux 3.10.0) 16 818258 CUVMC.AIS.COLUMBIA.EDU (VM/SP 4.0) 17 814814 LISTSERV.MIAMIOH.EDU (Windows Server 2016 Standard x64 Edition) 18 813671 LISTSERV.SYR.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 19 757037 LISTSERV.UH.EDU (Linux 3.10.0) 20 731861 LISTSERV.UC.EDU (Windows Server 2012 R2 Datacenter x64 Edition)
Pos Lists Site --- ----- ---- 1 34254 LISTES.ULAVAL.CA (Linux 3.10.0) 2 16515 LISTS.PSU.EDU (AIX 6.1) 3 12395 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 8112 MARIST (VM/SP 2.0) 7 8079 LISTSERV.TECHNION.AC.IL (Linux 2.6.32) 8 7624 LSV.UKY.EDU (Windows Server 2012 R2 Datacenter x64 Edition) 9 7218 LISTSERV.LIV.AC.UK (Linux 2.6.32) 10 6702 LISTSERV.MIAMIOH.EDU (Windows Server 2016 Standard x64 Edition) 11 6107 LISTSERV.UGA.EDU (Linux 2.6.32) 12 5467 LISTS.UMN.EDU (Linux 3.10.0) 13 5050 LISTSERV.TAMU.EDU (Linux 3.0.101) 14 4903 LS.KULEUVEN.BE (Linux 2.6.32) 15 4372 LISTSERV.UTORONTO.CA (Linux 3.10.0) 16 4185 LISTSERV.NODAK.EDU (Windows Server 2019 Standard x64 Edition) 17 4058 LISTSERV.SYR.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 18 4025 LISTSERV.MILLERSVILLE.EDU (Linux 2.6.32) 19 3998 LISTS.QUEENSU.CA (Linux 3.10.0) 20 3551 LISTSERV.BUFFALO.EDU (Linux 3.10.0)
Pos Recipients Site --- ---------- ---- 1 618634 JISCMAIL.AC.UK (Windows Server 2008 R2 Enterprise x64 Edition) 2 336014 LISTS.PSU.EDU (AIX 6.1) 3 271582 LIST.ETSI.ORG (Windows Server 2016 Datacenter x64 Edition) 4 256496 LISTSERV.LIV.AC.UK (Linux 2.6.32) 5 205842 LISTSERV.TAMU.EDU (Linux 3.0.101) 6 176835 LISTSERV.REDIRIS.ES (Linux 2.6.32-504.3.3.el6.x86_64) 7 168967 LISTS.HAWAII.EDU (Linux 2.6.32-754.24.3.el6.x86_64) 8 163414 LISTES.ULAVAL.CA (Linux 3.10.0) 9 155654 LISTSERV.UGA.EDU (Linux 2.6.32) 10 152667 LSV.UKY.EDU (Windows Server 2012 R2 Datacenter x64 Edition) 11 147487 CFSLIST.SA.GOV.AU (Windows Server 2012 R2 Datacenter x64 Edition) 12 140156 LISTSERV.BUFFALO.EDU (Linux 3.10.0) 13 133793 LISTSERV.NODAK.EDU (Windows Server 2019 Standard x64 Edition) 14 129629 LISTS.UFL.EDU (Linux 2.6.32) 15 128928 LISTSERV.UCONN.EDU (Windows Server 2012 R2 Standard x64 Edition) 16 128535 LISTSERV.SYR.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 17 123090 DISCUSSIONS.EQ.EDU.AU (Linux 3.10.0-957.12.2.el7.x86_64) 18 113904 LISTSERV.UIC.EDU (Linux 2.6.32-504.8.1.el6.x86_64) 19 110887 LISTSERV.AAP.ORG (Windows Server 2012 R2 Standard x64 Edition) 20 102770 LISTSERV.UA.EDU (Linux 4.12.14)
Pos Subscribers Site --- ----------- ---- 1 300656 COMPUTING@LIST.MSU.EDU (Linux 3.10.0) 2 59388 CAREERCENTERUPDATE@LISTSERV.UGA.EDU (Linux 2.6.32) 3 54050 AMIS-CNRS-INTERNATIONAL-L@IN2P3.FR (Linux 3.10.0) 4 42294 SAFETYNOTICE@LISTSERV.UC.EDU (Windows Server 2012 R2 Datacenter x64 Edition) 5 41763 OPSWNEWS@LISTSERV.NYSED.GOV (Linux 4.12.14) 6 37503 CMU-BASKETBALL@LS2.CMICH.EDU (Linux 3.10.0) 7 34587 TCUATHLETICSDIRECTOR@LISTSERV.TCU.EDU (Windows Server 2012 R2 Standard x64 Edition) 8 33600 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 28311 L-THON-NEWS@LISTS.PSU.EDU (AIX 6.1) 13 28058 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 24766 ISMA@LS.KULEUVEN.BE (Linux 2.6.32) 20 24454 EXCEL@LISTSERV.UTA.EDU (Windows Server 2008 R2 Enterprise x64 Edition)