![[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 702937 JISCMAIL.AC.UK (Windows Server 2008 R2 Enterprise x64 Edition) 2 227125 LISTS.PSU.EDU (AIX 6.1) 3 206381 DIGITAL.ANNEXBUSINESSMEDIA.COM (Linux 3.13.0-32-generic) 4 204978 LISTSERV.TAMU.EDU (Linux 3.0.101) 5 190143 LISTSERV.ACM.ORG (Windows Server 2012 R2 Datacenter x64 Edition) 6 172917 LISTSERV.LIV.AC.UK (Linux 2.6.32) 7 169673 LISTSERV.REDIRIS.ES (Linux 2.6.32-504.3.3.el6.x86_64) 8 144608 DISCUSSIONS.EQ.EDU.AU (Linux 2.6.18-404.el5) 9 138735 LISTSERV.UGA.EDU (Linux 2.6.32) 10 134477 LISTSERV.BUFFALO.EDU (Linux 3.10.0) 11 132460 LISTSERV.UA.EDU (Linux 3.0.101) 12 124802 LISTS.UFL.EDU (Linux 2.6.32) 13 120486 LISTSERV.ICORS.ORG (Windows Server 2012 R2 Datacenter x64 Edition) 14 120122 LIST.UVM.EDU (Linux 2.6.32) 15 118643 LISTSERV.DARTMOUTH.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 16 112256 LSV.UKY.EDU (Windows Server 2012 R2 Datacenter x64 Edition) 17 111646 LISTS.HAWAII.EDU (Linux 2.6.32-754.17.1.el6.x86_64) 18 107777 LISTSERV.SYR.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 19 105438 LISTSERV.TDBANK.CA (Windows Server 2012 R2 Datacenter x64 Edition) 20 101904 OCLCLISTS.ORG (Windows Server 2012 R2 Standard x64 Edition)
Pos Subscribers Site --- ----------- ---- 1 5073227 LISTS.PSU.EDU (AIX 6.1) 2 3675479 LISTES.ULAVAL.CA (Linux 3.10.0) 3 2180398 LS.KULEUVEN.BE (Linux 2.6.32) 4 1441191 LSV.UKY.EDU (Windows Server 2012 R2 Datacenter x64 Edition) 5 1432858 LISTSERV.TAU.AC.IL (Linux 2.6.9) 6 1408875 LISTSERV.UGA.EDU (Linux 2.6.32) 7 1282581 LISTSERV.UTORONTO.CA (Linux 3.10.0) 8 1273971 LISTSERV.TAMU.EDU (Linux 3.0.101) 9 1143126 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 818258 CUVMC.AIS.COLUMBIA.EDU (VM/SP 4.0) 14 804944 LISTSERV.BUFFALO.EDU (Linux 3.10.0) 15 804714 LISTSERV.UA.EDU (Linux 3.0.101) 16 774256 LISTSERV.NODAK.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 17 750105 LISTSERV.MIAMIOH.EDU (Windows Server 2016 Standard x64 Edition) 18 746151 LISTSERV.ECU.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 19 745882 LISTSERV.SYR.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 20 738807 LISTSERV.UH.EDU (Linux 3.10.0)
Pos Lists Site --- ----- ---- 1 27490 LISTES.ULAVAL.CA (Linux 3.10.0) 2 16825 LISTS.PSU.EDU (AIX 6.1) 3 14243 LSV.UKY.EDU (Windows Server 2012 R2 Datacenter x64 Edition) 4 14009 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 7668 MARIST (VM/SP 2.0) 9 7056 LISTSERV.LIV.AC.UK (Linux 2.6.32) 10 6681 LISTSERV.MIAMIOH.EDU (Windows Server 2016 Standard x64 Edition) 11 5897 LISTSERV.UGA.EDU (Linux 2.6.32) 12 5467 LISTS.UMN.EDU (Linux 2.6.32) 13 5074 LISTSERV.TAMU.EDU (Linux 3.0.101) 14 4603 LS.KULEUVEN.BE (Linux 2.6.32) 15 4372 LISTSERV.UTORONTO.CA (Linux 3.10.0) 16 4342 LISTSERV.NODAK.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 17 3998 LISTS.QUEENSU.CA (Linux 3.10.0) 18 3982 LISTSERV.MILLERSVILLE.EDU (Linux 2.6.32) 19 3939 LISTSERV.SYR.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 20 3486 LISTSERV.BUFFALO.EDU (Linux 3.10.0)
Pos Recipients Site --- ---------- ---- 1 676040 JISCMAIL.AC.UK (Windows Server 2008 R2 Enterprise x64 Edition) 2 222777 LISTS.PSU.EDU (AIX 6.1) 3 203875 LISTSERV.TAMU.EDU (Linux 3.0.101) 4 167354 LISTSERV.REDIRIS.ES (Linux 2.6.32-504.3.3.el6.x86_64) 5 166221 LISTSERV.LIV.AC.UK (Linux 2.6.32) 6 144488 DISCUSSIONS.EQ.EDU.AU (Linux 2.6.18-404.el5) 7 135718 LISTSERV.UGA.EDU (Linux 2.6.32) 8 130791 LISTSERV.BUFFALO.EDU (Linux 3.10.0) 9 127604 LISTSERV.UA.EDU (Linux 3.0.101) 10 123625 LISTS.UFL.EDU (Linux 2.6.32) 11 118670 LISTSERV.ICORS.ORG (Windows Server 2012 R2 Datacenter x64 Edition) 12 118295 LIST.UVM.EDU (Linux 2.6.32) 13 115837 LISTSERV.DARTMOUTH.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 14 110323 LISTS.HAWAII.EDU (Linux 2.6.32-754.17.1.el6.x86_64) 15 109975 LSV.UKY.EDU (Windows Server 2012 R2 Datacenter x64 Edition) 16 99387 LISTSERV.AAP.ORG (Windows Server 2012 R2 Standard x64 Edition) 17 98695 LISTSERV.UCONN.EDU (Windows Server 2012 R2 Standard x64 Edition) 18 97220 LISTSERV.NODAK.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 19 97161 LISTS.VATRAFFIC.ORG (Windows Server 2012 R2 Datacenter x64 Edition) 20 94130 LISTS.UMN.EDU (Linux 2.6.32)
Pos Subscribers Site --- ----------- ---- 1 300656 COMPUTING@LIST.MSU.EDU (Linux 3.10.0) 2 61613 CAREERCENTERUPDATE@LISTSERV.UGA.EDU (Linux 2.6.32) 3 54050 AMIS-CNRS-INTERNATIONAL-L@IN2P3.FR (Linux 3.10.0) 4 49043 SAFETYNOTICE@LISTSERV.UC.EDU (Windows Server 2012 R2 Datacenter x64 Edition) 5 41763 OPSWNEWS@LISTSERV.NYSED.GOV (Linux 4.12.14) 6 36548 CMU-BASKETBALL@LS2.CMICH.EDU (Linux 3.10.0) 7 34587 TCUATHLETICSDIRECTOR@LISTSERV.TCU.EDU (Windows Server 2012 R2 Standard x64 Edition) 8 33602 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 28436 HALLCOLIBRARY-L@LISTSERV.UGA.EDU (Linux 2.6.32) 13 28316 L-THON-NEWS@LISTS.PSU.EDU (AIX 6.1) 14 27710 RECREATION@LISTSERV.MIAMIOH.EDU (Windows Server 2016 Standard x64 Edition) 15 27401 VOLUPDATE@LISTSERV.UTK.EDU (Solaris 2.10) 16 26418 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 24765 ISMA@LS.KULEUVEN.BE (Linux 2.6.32) 20 24492 EXCEL@LISTSERV.UTA.EDU (Windows Server 2008 R2 Enterprise x64 Edition)