![[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 576804 JISCMAIL.AC.UK (Windows Server 2008 R2 Enterprise x64 Edition) 2 423216 LISTS.PSU.EDU (AIX 6.1) 3 402829 LISTSERV.TAMU.EDU (Linux 3.0.101) 4 227447 LISTSERV.UGA.EDU (Linux 2.6.32) 5 221417 DISCUSSIONS.EQ.EDU.AU (Linux 2.6.18-404.el5) 6 221027 LISTS.HAWAII.EDU (Linux 2.6.32-696.23.1.el6.x86_64) 7 220106 LISTSERV.BUFFALO.EDU (Solaris 2.11) 8 219041 LIST.ETSI.ORG (Windows Server 2016 Datacenter x64 Edition) 9 217972 DIGITAL.ANNEXBUSINESSMEDIA.COM (Linux 3.13.0-32-generic) 10 193112 LISTSERV.ACM.ORG (Windows Server 2012 R2 Datacenter x64 Edition) 11 189270 LSERV.FLDOE.ORG (Windows Server 2012 R2 Standard x64 Edition) 12 178533 LSV.UKY.EDU (Windows Server 2012 R2 Datacenter x64 Edition) 13 167459 LISTSERV.SYR.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 14 162843 LISTS.UFL.EDU (Linux 2.6.18) 15 151814 LISTSERV.ICORS.ORG (Windows Server 2012 R2 Datacenter x64 Edition) 16 146985 LISTSERV.LIV.AC.UK (Linux 2.6.32) 17 130651 LISTS.UCDENVER.EDU (Windows Server 2012 R2 Standard x64 Edition) 18 130421 LISTS.UMN.EDU (Linux 2.6.32) 19 128007 LISTSERV.NODAK.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 20 125871 LIST.UVM.EDU (Linux 2.6.32)
Pos Subscribers Site --- ----------- ---- 1 5456486 LISTS.PSU.EDU (AIX 6.1) 2 4511570 LISTES.ULAVAL.CA (Linux 2.6.18) 3 2155674 LS.KULEUVEN.BE (Linux 2.6.32) 4 1414378 LISTSERV.TAU.AC.IL (Linux 2.6.9) 5 1371658 LSV.UKY.EDU (Windows Server 2012 R2 Datacenter x64 Edition) 6 1282581 LISTSERV.UTORONTO.CA (Linux 2.6.18) 7 1269280 LISTSERV.TAMU.EDU (Linux 3.0.101) 8 1268969 LISTSERV.UGA.EDU (Linux 2.6.32) 9 1120701 LISTS.WAYNE.EDU (Linux 2.6.32) 10 1059036 LISTS.UFL.EDU (Linux 2.6.18) 11 1003954 LISTS.UMN.EDU (Linux 2.6.32) 12 944029 LIST.MSU.EDU (Linux 3.10.0) 13 848160 LISTSERV.BUFFALO.EDU (Solaris 2.11) 14 818258 CUVMC.AIS.COLUMBIA.EDU (VM/SP 4.0) 15 811771 LISTSERV.NODAK.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 16 765864 LISTSERV.SYR.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 17 764189 LISTSERV.UH.EDU (Linux 3.10.0) 18 748669 LISTSERV.UA.EDU (Linux 3.0.101) 19 746780 LISTSERV.ECU.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 20 733741 LISTSERV.MIAMIOH.EDU (Windows Server 2012 R2 Standard x64 Edition)
Pos Lists Site --- ----- ---- 1 33844 LISTES.ULAVAL.CA (Linux 2.6.18) 2 16831 LISTS.PSU.EDU (AIX 6.1) 3 14172 LSV.UKY.EDU (Windows Server 2012 R2 Datacenter x64 Edition) 4 13731 LISTSERV.TAU.AC.IL (Linux 2.6.9) 5 9788 LISTS.CLEMSON.EDU (Linux 2.6.18) 6 9599 LISTS.UFL.EDU (Linux 2.6.18) 7 8076 LISTSERV.TECHNION.AC.IL (Linux 2.6.32) 8 7439 MARIST (VM/SP 2.0) 9 6605 LISTSERV.MIAMIOH.EDU (Windows Server 2012 R2 Standard x64 Edition) 10 6519 LISTSERV.LIV.AC.UK (Linux 2.6.32) 11 5511 LISTS.UMN.EDU (Linux 2.6.32) 12 5494 LISTSERV.UGA.EDU (Linux 2.6.32) 13 5091 LISTSERV.TAMU.EDU (Linux 3.0.101) 14 4442 LISTSERV.NODAK.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 15 4372 LISTSERV.UTORONTO.CA (Linux 2.6.18) 16 4302 LS.KULEUVEN.BE (Linux 2.6.32) 17 3880 LISTS.QUEENSU.CA (Solaris 2.10) 18 3859 LISTSERV.MILLERSVILLE.EDU (Linux 2.6.32) 19 3834 LISTSERV.SYR.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 20 3659 YORKU.CA (Linux 2.6.32)
Pos Recipients Site --- ---------- ---- 1 552937 JISCMAIL.AC.UK (Windows Server 2008 R2 Enterprise x64 Edition) 2 418243 LISTS.PSU.EDU (AIX 6.1) 3 401925 LISTSERV.TAMU.EDU (Linux 3.0.101) 4 222366 LISTSERV.UGA.EDU (Linux 2.6.32) 5 221215 DISCUSSIONS.EQ.EDU.AU (Linux 2.6.18-404.el5) 6 219949 LISTS.HAWAII.EDU (Linux 2.6.32-696.23.1.el6.x86_64) 7 218384 LIST.ETSI.ORG (Windows Server 2016 Datacenter x64 Edition) 8 215955 LISTSERV.BUFFALO.EDU (Solaris 2.11) 9 189272 LSERV.FLDOE.ORG (Windows Server 2012 R2 Standard x64 Edition) 10 175747 LSV.UKY.EDU (Windows Server 2012 R2 Datacenter x64 Edition) 11 160991 LISTS.UFL.EDU (Linux 2.6.18) 12 148465 LISTSERV.ICORS.ORG (Windows Server 2012 R2 Datacenter x64 Edition) 13 139689 LISTSERV.LIV.AC.UK (Linux 2.6.32) 14 131815 LISTSERV.SYR.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 15 130609 LISTS.UCDENVER.EDU (Windows Server 2012 R2 Standard x64 Edition) 16 127383 LISTS.UMN.EDU (Linux 2.6.32) 17 126977 LISTSERV.NODAK.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 18 124614 LISTSERV.UCONN.EDU (Windows Server 2012 R2 Standard x64 Edition) 19 124138 LIST.UVM.EDU (Linux 2.6.32) 20 116442 LISTSERV.AAP.ORG (Windows Server 2012 R2 Standard x64 Edition)
Pos Subscribers Site --- ----------- ---- 1 300656 COMPUTING@LIST.MSU.EDU (Linux 3.10.0) 2 62400 EXCEL@LISTSERV.UTA.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 3 54050 AMIS-CNRS-INTERNATIONAL-L@IN2P3.FR (Linux 3.10.0) 4 41763 OPSWNEWS@LISTSERV.NYSED.GOV (AIX 7.1) 5 41647 SAFETYNOTICE@LISTSERV.UC.EDU (Windows Server 2012 R2 Datacenter x64 Edition) 6 35710 CMU-BASKETBALL@LS2.CMICH.EDU (Linux 3.10.0) 7 34587 TCUATHLETICSDIRECTOR@LISTSERV.TCU.EDU (Windows Server 2012 R2 Standard x64 Edition) 8 33607 L-SMEAL-REPORT@LISTS.PSU.EDU (AIX 6.1) 9 30836 FOCIS_GROUP@LISTS.WAYNE.EDU (Linux 2.6.32) 10 29333 CAREERCENTERUPDATE@LISTSERV.UGA.EDU (Linux 2.6.32) 11 28992 HALLCOLIBRARY-L@LISTSERV.UGA.EDU (Linux 2.6.32) 12 28918 BEDRIJVENLIJST@LS.KULEUVEN.BE (Linux 2.6.32) 13 28918 BEDRIJVENLIJST2@LS.KULEUVEN.BE (Linux 2.6.32) 14 28328 L-THON-NEWS@LISTS.PSU.EDU (AIX 6.1) 15 27709 RECREATION@LISTSERV.MIAMIOH.EDU (Windows Server 2012 R2 Standard x64 Edition) 16 27405 VOLUPDATE@LISTSERV.UTK.EDU (Solaris 2.10) 17 27079 HINDU-D@LISTSERV.NODAK.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 18 26418 PARENTS@LISTSERV.TAMU.EDU (Linux 3.0.101) 19 24990 NCHPAD-NEWS@LISTSERV.UAB.EDU (Linux 2.6.32) 20 24869 CANVASSTUDENTS_AUTO@LISTSERV.MIAMIOH.EDU (Windows Server 2012 R2 Standard x64 Edition)