![[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 867235 JISCMAIL.AC.UK (Windows Server 2008 R2 Enterprise x64 Edition) 2 687758 LISTSERV.TAMU.EDU (Linux 3.0.101) 3 440247 LISTS.PSU.EDU (AIX 6.1) 4 310127 LISTSERV.LIV.AC.UK (Linux 2.6.32) 5 256635 LISTSERV.UGA.EDU (Linux 2.6.32) 6 254939 LISTES.ULAVAL.CA (Linux 3.10.0) 7 254485 DISCUSSIONS.EQ.EDU.AU (Linux 2.6.18-404.el5) 8 236308 LISTSERV.SYR.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 9 235897 LISTS.UCDENVER.EDU (Windows Server 2012 R2 Standard x64 Edition) 10 226138 DIGITAL.ANNEXBUSINESSMEDIA.COM (Linux 3.13.0-32-generic) 11 219245 LISTS.UFL.EDU (Linux 2.6.32) 12 217410 LISTSERV.BUFFALO.EDU (Solaris 2.11) 13 208456 LSV.UKY.EDU (Windows Server 2012 R2 Datacenter x64 Edition) 14 208302 LISTSERV.REDIRIS.ES (Linux 2.6.32-504.3.3.el6.x86_64) 15 204324 LISTSERV.ACM.ORG (Windows Server 2012 R2 Datacenter x64 Edition) 16 186914 LIST.ETSI.ORG (Windows Server 2016 Datacenter x64 Edition) 17 184099 LISTSERV.DARTMOUTH.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 18 180514 LISTS.HAWAII.EDU (Linux 2.6.32-754.10.1.el6.x86_64) 19 174920 LISTSERV.UIC.EDU (Linux 2.6.32-504.8.1.el6.x86_64) 20 166251 LISTSERV.UCONN.EDU (Windows Server 2012 R2 Standard x64 Edition)
Pos Subscribers Site --- ----------- ---- 1 5050684 LISTS.PSU.EDU (AIX 6.1) 2 3788024 LISTES.ULAVAL.CA (Linux 3.10.0) 3 2201948 LS.KULEUVEN.BE (Linux 2.6.32) 4 1406572 LISTSERV.TAU.AC.IL (Linux 2.6.9) 5 1378097 LISTSERV.UGA.EDU (Linux 2.6.32) 6 1371297 LSV.UKY.EDU (Windows Server 2012 R2 Datacenter x64 Edition) 7 1292057 LISTSERV.TAMU.EDU (Linux 3.0.101) 8 1282581 LISTSERV.UTORONTO.CA (Linux 3.10.0) 9 1132722 LISTS.WAYNE.EDU (Linux 2.6.32) 10 1059036 LISTS.UFL.EDU (Linux 2.6.32) 11 982099 LISTS.UMN.EDU (Linux 2.6.32) 12 944029 LIST.MSU.EDU (Linux 3.10.0) 13 826119 LISTSERV.BUFFALO.EDU (Solaris 2.11) 14 820181 LISTSERV.UA.EDU (Linux 3.0.101) 15 818258 CUVMC.AIS.COLUMBIA.EDU (VM/SP 4.0) 16 812309 LISTSERV.NODAK.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 17 793193 LISTSERV.MIAMIOH.EDU (Windows Server 2012 R2 Standard x64 Edition) 18 790139 LISTSERV.UH.EDU (Linux 3.10.0) 19 762625 LISTSERV.SYR.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 20 743757 LISTSERV.ECU.EDU (Windows Server 2008 R2 Enterprise x64 Edition)
Pos Lists Site --- ----- ---- 1 27270 LISTES.ULAVAL.CA (Linux 3.10.0) 2 16917 LISTS.PSU.EDU (AIX 6.1) 3 14272 LSV.UKY.EDU (Windows Server 2012 R2 Datacenter x64 Edition) 4 13342 LISTSERV.TAU.AC.IL (Linux 2.6.9) 5 9788 LISTS.CLEMSON.EDU (Linux 2.6.18) 6 9599 LISTS.UFL.EDU (Linux 2.6.32) 7 8079 LISTSERV.TECHNION.AC.IL (Linux 2.6.32) 8 7622 MARIST (VM/SP 2.0) 9 7459 LISTSERV.UH.EDU (Linux 3.10.0) 10 6930 LISTSERV.LIV.AC.UK (Linux 2.6.32) 11 6666 LISTSERV.MIAMIOH.EDU (Windows Server 2012 R2 Standard x64 Edition) 12 5722 LISTSERV.UGA.EDU (Linux 2.6.32) 13 5467 LISTS.UMN.EDU (Linux 2.6.32) 14 5098 LISTSERV.TAMU.EDU (Linux 3.0.101) 15 4493 LS.KULEUVEN.BE (Linux 2.6.32) 16 4429 LISTSERV.NODAK.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 17 4372 LISTSERV.UTORONTO.CA (Linux 3.10.0) 18 3979 LISTS.QUEENSU.CA (Solaris 2.10) 19 3974 LISTSERV.MILLERSVILLE.EDU (Linux 2.6.32) 20 3915 LISTSERV.SYR.EDU (Windows Server 2008 R2 Enterprise x64 Edition)
Pos Recipients Site --- ---------- ---- 1 837820 JISCMAIL.AC.UK (Windows Server 2008 R2 Enterprise x64 Edition) 2 686506 LISTSERV.TAMU.EDU (Linux 3.0.101) 3 435380 LISTS.PSU.EDU (AIX 6.1) 4 296231 LISTSERV.LIV.AC.UK (Linux 2.6.32) 5 254733 LISTES.ULAVAL.CA (Linux 3.10.0) 6 254301 DISCUSSIONS.EQ.EDU.AU (Linux 2.6.18-404.el5) 7 250584 LISTSERV.UGA.EDU (Linux 2.6.32) 8 235873 LISTS.UCDENVER.EDU (Windows Server 2012 R2 Standard x64 Edition) 9 217861 LISTS.UFL.EDU (Linux 2.6.32) 10 212223 LISTSERV.BUFFALO.EDU (Solaris 2.11) 11 205444 LSV.UKY.EDU (Windows Server 2012 R2 Datacenter x64 Edition) 12 205416 LISTSERV.REDIRIS.ES (Linux 2.6.32-504.3.3.el6.x86_64) 13 192974 LISTSERV.SYR.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 14 186441 LIST.ETSI.ORG (Windows Server 2016 Datacenter x64 Edition) 15 180802 LISTSERV.DARTMOUTH.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 16 179732 LISTS.HAWAII.EDU (Linux 2.6.32-754.10.1.el6.x86_64) 17 174645 LISTSERV.UIC.EDU (Linux 2.6.32-504.8.1.el6.x86_64) 18 165395 LISTSERV.UCONN.EDU (Windows Server 2012 R2 Standard x64 Edition) 19 159375 LISTSERV.NODAK.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 20 158796 LIST.UVM.EDU (Linux 2.6.32)
Pos Subscribers Site --- ----------- ---- 1 300656 COMPUTING@LIST.MSU.EDU (Linux 3.10.0) 2 62355 EXCEL@LISTSERV.UTA.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 3 61884 CAREERCENTERUPDATE@LISTSERV.UGA.EDU (Linux 2.6.32) 4 54050 AMIS-CNRS-INTERNATIONAL-L@IN2P3.FR (Linux 3.10.0) 5 44354 SAFETYNOTICE@LISTSERV.UC.EDU (Windows Server 2012 R2 Datacenter x64 Edition) 6 41763 OPSWNEWS@LISTSERV.NYSED.GOV (Linux 4.4.162) 7 36727 CMU-BASKETBALL@LS2.CMICH.EDU (Linux 3.10.0) 8 34587 TCUATHLETICSDIRECTOR@LISTSERV.TCU.EDU (Windows Server 2012 R2 Standard x64 Edition) 9 33602 L-SMEAL-REPORT@LISTS.PSU.EDU (AIX 6.1) 10 31681 CENTERFORMICROBIOLOGY@LS.KULEUVEN.BE (Linux 2.6.32) 11 30835 FOCIS_GROUP@LISTS.WAYNE.EDU (Linux 2.6.32) 12 29481 HALLCOLIBRARY-L@LISTSERV.UGA.EDU (Linux 2.6.32) 13 28918 BEDRIJVENLIJST@LS.KULEUVEN.BE (Linux 2.6.32) 14 28918 BEDRIJVENLIJST2@LS.KULEUVEN.BE (Linux 2.6.32) 15 28316 L-THON-NEWS@LISTS.PSU.EDU (AIX 6.1) 16 27709 RECREATION@LISTSERV.MIAMIOH.EDU (Windows Server 2012 R2 Standard x64 Edition) 17 27401 VOLUPDATE@LISTSERV.UTK.EDU (Solaris 2.10) 18 27079 HINDU-D@LISTSERV.NODAK.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 19 26418 PARENTS@LISTSERV.TAMU.EDU (Linux 3.0.101) 20 24991 NCHPAD-NEWS@LISTSERV.UAB.EDU (Linux 2.6.32)