![[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 681791 JISCMAIL.AC.UK (Windows Server 2008 R2 Enterprise x64 Edition) 2 235581 LSERV.CARDSYS.AT (Linux 4.4.59-1-pve) 3 225964 LISTS.PSU.EDU (AIX 6.1) 4 214390 DIGITAL.ANNEXBUSINESSMEDIA.COM (Linux 3.13.0-32-generic) 5 204028 LISTSERV.BUFFALO.EDU (Solaris 2.11) 6 188075 LISTSERV.TAMU.EDU (Linux 3.0.101) 7 173227 LISTSERV.REDIRIS.ES (Linux 2.6.32-504.3.3.el6.x86_64) 8 164536 LISTSERV.LIV.AC.UK (Linux 2.6.32) 9 162843 LISTSERV.ACM.ORG (Windows Server 2008 R2 Datacenter x64 Edition) 10 156517 LISTSERV.SYR.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 11 149569 LSV.UKY.EDU (Windows Server 2012 R2 Datacenter x64 Edition) 12 147283 LISTSERV.ICORS.ORG (Windows Server 2008 R2 Datacenter x64 Edition) 13 146172 DISCUSSIONS.EQ.EDU.AU (Linux 2.6.18-404.el5) 14 143703 H-NET.MSU.EDU (Linux 2.6.32) 15 143297 LISTSERV.DARTMOUTH.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 16 128337 LISTSERV.UGA.EDU (Linux 2.6.32) 17 125175 LISTSERV.UMD.EDU (SunOS 5.10) 18 121764 LISTS.UFL.EDU (Linux 2.6.18) 19 112166 LISTSERV.UA.EDU (Linux 3.0.101) 20 108822 LISTSERV.AAP.ORG (Windows Server 2003 R2 + LSMTP V1.1b)
Pos Subscribers Site --- ----------- ---- 1 4861268 LISTS.PSU.EDU (AIX 6.1) 2 3549266 LISTES.ULAVAL.CA (Linux 2.6.18) 3 1814009 LS.KULEUVEN.BE (Linux 2.6.32) 4 1554921 LISTS.WAYNE.EDU (Linux 2.6.18) 5 1364265 LISTSERV.TAU.AC.IL (Linux 2.6.9) 6 1309953 LSV.UKY.EDU (Windows Server 2012 R2 Datacenter x64 Edition) 7 1302523 LISTSERV.TAMU.EDU (Linux 3.0.101) 8 1245769 LISTSERV.UGA.EDU (Linux 2.6.32) 9 1059036 LISTS.UFL.EDU (Linux 2.6.18) 10 1026647 LISTSERV.BUFFALO.EDU (Solaris 2.11) 11 993015 LIST.MSU.EDU (Linux 3.0.34) 12 962447 LISTS.UMN.EDU (Linux 2.6.32) 13 939706 LISTSERV.UTORONTO.CA (Linux 2.6.18) 14 926096 LISTSERV.ND.EDU (Linux 2.6.18) 15 906863 LISTSERV.UA.EDU (Linux 3.0.101) 16 818258 CUVMC.AIS.COLUMBIA.EDU (VM/SP 4.0) 17 788863 LISTSERV.UH.EDU (Linux 2.6.18) 18 759481 LISTSERV.SYR.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 19 750459 LISTSERV.NODAK.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 20 705603 LISTSERV.MIAMIOH.EDU (Windows Server 2012 R2 Standard x64 Edition)
Pos Lists Site --- ----- ---- 1 26831 LISTES.ULAVAL.CA (Linux 2.6.18) 2 15190 LISTS.PSU.EDU (AIX 6.1) 3 14007 LSV.UKY.EDU (Windows Server 2012 R2 Datacenter x64 Edition) 4 13449 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 7512 LISTSERV.TECHNION.AC.IL (Linux 2.6.32) 8 6845 MARIST (VM/SP 2.0) 9 6655 LISTSERV.TAMU.EDU (Linux 3.0.101) 10 6505 LISTSERV.MIAMIOH.EDU (Windows Server 2012 R2 Standard x64 Edition) 11 6074 LISTSERV.LIV.AC.UK (Linux 2.6.32) 12 5721 LISTSERV.MILLERSVILLE.EDU (Linux 2.6.32) 13 5502 LISTS.UMN.EDU (Linux 2.6.32) 14 4918 LISTSERV.UGA.EDU (Linux 2.6.32) 15 4378 LISTSERV.NODAK.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 16 4104 LISTSERV.UTORONTO.CA (Linux 2.6.18) 17 3992 LISTSERV.ND.EDU (Linux 2.6.18) 18 3890 LS.KULEUVEN.BE (Linux 2.6.32) 19 3759 LISTS.QUEENSU.CA (Solaris 2.10) 20 3613 LISTSERV.SYR.EDU (Windows Server 2008 R2 Enterprise x64 Edition)
Pos Recipients Site --- ---------- ---- 1 657126 JISCMAIL.AC.UK (Windows Server 2008 R2 Enterprise x64 Edition) 2 221343 LISTS.PSU.EDU (AIX 6.1) 3 199603 LISTSERV.BUFFALO.EDU (Solaris 2.11) 4 186836 LISTSERV.TAMU.EDU (Linux 3.0.101) 5 170447 LISTSERV.REDIRIS.ES (Linux 2.6.32-504.3.3.el6.x86_64) 6 156782 LISTSERV.LIV.AC.UK (Linux 2.6.32) 7 146657 LSV.UKY.EDU (Windows Server 2012 R2 Datacenter x64 Edition) 8 146026 DISCUSSIONS.EQ.EDU.AU (Linux 2.6.18-404.el5) 9 144085 LISTSERV.ICORS.ORG (Windows Server 2008 R2 Datacenter x64 Edition) 10 141885 H-NET.MSU.EDU (Linux 2.6.32) 11 138217 LISTSERV.DARTMOUTH.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 12 135149 LISTSERV.SYR.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 13 125004 LISTSERV.UGA.EDU (Linux 2.6.32) 14 120165 LISTS.UFL.EDU (Linux 2.6.18) 15 110090 LISTSERV.UMD.EDU (SunOS 5.10) 16 108522 LISTSERV.AAP.ORG (Windows Server 2003 R2 + LSMTP V1.1b) 17 107236 LISTSERV.UA.EDU (Linux 3.0.101) 18 104443 LISTS.HAWAII.EDU (Linux 2.6.32-696.1.1.el6.x86_64) 19 103352 LISTSERV.UIC.EDU (Linux 2.6.32-504.8.1.el6.x86_64) 20 101667 LISTS.UCDENVER.EDU (Windows Server 2012 R2 Standard x64 Edition)
Pos Subscribers Site --- ----------- ---- 1 300671 COMPUTING@LIST.MSU.EDU (Linux 3.0.34) 2 62512 EXCEL@LISTSERV.UTA.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 3 55923 CAREERCENTERUPDATE@LISTSERV.UGA.EDU (Linux 2.6.32) 4 54050 AMIS-CNRS-INTERNATIONAL-L@IN2P3.FR (AIX 5.3) 5 41736 OPSWNEWS@LISTSERV.NYSED.GOV (AIX 7.1) 6 37584 SAFETYNOTICE@LISTSERV.UC.EDU (Windows Server 2012 R2 Datacenter x64 Edition) 7 34918 ASMSU@LIST.MSU.EDU (Linux 3.0.34) 8 34587 TCUATHLETICSDIRECTOR@LISTSERV.TCU.EDU (Windows Server 2012 R2 Standard x64 Edition) 9 34079 CMU-BASKETBALL@LS2.CMICH.EDU (Linux 2.6.18) 10 33617 L-SMEAL-REPORT@LISTS.PSU.EDU (AIX 6.1) 11 30848 FOCIS_GROUP@LISTS.WAYNE.EDU (Linux 2.6.18) 12 29086 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 28356 L-THON-NEWS@LISTS.PSU.EDU (AIX 6.1) 16 27713 RECREATION@LISTSERV.MIAMIOH.EDU (Windows Server 2012 R2 Standard x64 Edition) 17 27534 TAU-BOGRIM@LISTSERV.TAU.AC.IL (Linux 2.6.9) 18 27418 VOLUPDATE@LISTSERV.UTK.EDU (Solaris 2.10) 19 26420 PARENTS@LISTSERV.TAMU.EDU (Linux 3.0.101) 20 26101 CSTORE@LIST.MSU.EDU (Linux 3.0.34)