![[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 652116 JISCMAIL.AC.UK (Windows Server 2008 R2 Enterprise x64 Edition) 2 427284 NEWSMAIL.WYANOKEGROUP.COM (Windows Server 2008 R2 Standard x64 Edition) 3 399890 LISTS.PSU.EDU (AIX 6.1) 4 344195 LISTSERV.BUFFALO.EDU (Solaris 2.11) 5 280101 LISTSERV.ICORS.ORG (Windows Server 2008 R2 Datacenter x64 Edition) 6 279192 LISTS.UFL.EDU (Linux 2.6.18) 7 258757 LISTSERV.MED.CORNELL.EDU (SunOS 5.10) 8 242728 LISTSERV.UGA.EDU (Linux 2.6.32) 9 235064 LSV.UKY.EDU (Windows Server 2003) 10 219439 PO.MISSOURI.EDU (Windows Server 2012 R2 Standard x64 Edition) 11 205694 LISTSERV.TAMU.EDU (Linux 3.0.101) 12 201242 LISTSERV.SYR.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 13 185247 LISTSERV.UMD.EDU (SunOS 5.10) 14 182177 DISCUSSIONS.EQ.EDU.AU (Linux 2.6.18-404.el5) 15 161357 LISTSERV.ACM.ORG (Windows Server 2008 R2 Datacenter x64 Edition) 16 159830 LSERV.CARDSYS.AT (Linux 2.6.32-39-pve) 17 159787 AOPAMAILER.AOPA2.ORG (Windows Server 2008 R2 Datacenter x64 Edition) 18 141710 LISTS.ASU.EDU (Linux 2.6.18) 19 141705 LISTSERV.UIC.EDU (Linux 2.6.32-504.8.1.el6.x86_64) 20 137942 LISTS.HAWAII.EDU (Linux 2.6.32-504.16.2.el6.x86_64)
Pos Subscribers Site --- ----------- ---- 1 4712294 LISTS.PSU.EDU (AIX 6.1) 2 4414322 LISTES.ULAVAL.CA (Linux 2.6.18) 3 1537091 LISTSERV.UGA.EDU (Linux 2.6.32) 4 1514638 LISTS.WAYNE.EDU (Linux 2.6.18) 5 1514168 LSV.UKY.EDU (Windows Server 2003) 6 1389396 LISTSERV.TAU.AC.IL (Linux 2.6.9) 7 1375117 HERMES.GWU.EDU (Linux 2.6.32) 8 1207079 LISTSERV.CC.KULEUVEN.AC.BE (Linux 2.6.18) 9 1085671 LISTSERV.TAMU.EDU (Linux 3.0.101) 10 1059036 LISTS.UFL.EDU (Linux 2.6.18) 11 1025481 LISTS.UMN.EDU (Solaris 2.10) 12 931312 LIST.MSU.EDU (Linux 3.0.34) 13 892237 LISTSERV.ND.EDU (Linux 2.6.18) 14 867362 CUVMC.AIS.COLUMBIA.EDU (VM/SP 4.0) 15 849843 LISTSERV.UTORONTO.CA (Linux 2.6.18) 16 784799 LISTSERV.UA.EDU (Linux 3.0.82) 17 766312 LISTSERV.BUFFALO.EDU (Solaris 2.11) 18 751295 LISTS.ASU.EDU (Linux 2.6.18) 19 713817 LISTSERV.MIAMIOH.EDU (Windows Server 2012 R2 Standard x64 Edition) 20 678368 LISTSERV.TECHNION.AC.IL (Linux 2.6.32)
Pos Lists Site --- ----- ---- 1 56612 LSV.UKY.EDU (Windows Server 2003) 2 31863 LISTES.ULAVAL.CA (Linux 2.6.18) 3 14472 LISTS.PSU.EDU (AIX 6.1) 4 12993 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 8328 LISTSERV.CC.KULEUVEN.AC.BE (Linux 2.6.18) 8 7236 HERMES.GWU.EDU (Linux 2.6.32) 9 6658 LISTSERV.UGA.EDU (Linux 2.6.32) 10 6564 MARIST (VM/SP 2.0) 11 6142 LISTSERV.TECHNION.AC.IL (Linux 2.6.32) 12 6085 LISTS.UMN.EDU (Solaris 2.10) 13 6064 LISTSERV.MIAMIOH.EDU (Windows Server 2012 R2 Standard x64 Edition) 14 6062 LISTSERV.TAMU.EDU (Linux 3.0.101) 15 5126 LISTSERV.LIV.AC.UK (Linux 2.6.32) 16 4222 LISTSERV.NODAK.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 17 4003 LISTSERV.ND.EDU (Linux 2.6.18) 18 3743 LISTSERV.MILLERSVILLE.EDU (Linux 2.6.32) 19 3401 LISTSERV.SYR.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 20 3327 YORKU.CA (Linux 2.6.32)
Pos Recipients Site --- ---------- ---- 1 630929 JISCMAIL.AC.UK (Windows Server 2008 R2 Enterprise x64 Edition) 2 394939 LISTS.PSU.EDU (AIX 6.1) 3 340527 LISTSERV.BUFFALO.EDU (Solaris 2.11) 4 275617 LISTS.UFL.EDU (Linux 2.6.18) 5 273450 LISTSERV.ICORS.ORG (Windows Server 2008 R2 Datacenter x64 Edition) 6 257976 LISTSERV.MED.CORNELL.EDU (SunOS 5.10) 7 235937 LISTSERV.UGA.EDU (Linux 2.6.32) 8 231826 LSV.UKY.EDU (Windows Server 2003) 9 218943 PO.MISSOURI.EDU (Windows Server 2012 R2 Standard x64 Edition) 10 203640 LISTSERV.TAMU.EDU (Linux 3.0.101) 11 182032 DISCUSSIONS.EQ.EDU.AU (Linux 2.6.18-404.el5) 12 179772 LISTSERV.SYR.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 13 159699 LISTSERV.UMD.EDU (SunOS 5.10) 14 141191 LISTSERV.UIC.EDU (Linux 2.6.32-504.8.1.el6.x86_64) 15 136864 LISTS.HAWAII.EDU (Linux 2.6.32-504.16.2.el6.x86_64) 16 133266 LISTSERV.ND.EDU (Linux 2.6.18) 17 123719 LISTS.ASU.EDU (Linux 2.6.18) 18 123273 LISTS.UMN.EDU (Solaris 2.10) 19 118385 LIST.UVM.EDU (Linux 2.6.32) 20 115811 LISTSERV.UA.EDU (Linux 3.0.82)
Pos Subscribers Site --- ----------- ---- 1 300460 COMPUTING@LIST.MSU.EDU (Linux 3.0.34) 2 299361 NYSTEACHING@LISTSERV.NYSED.GOV (AIX 7.1) 3 109672 COMNET@HERMES.GWU.EDU (Linux 2.6.32) 4 80208 CAREERCENTERUPDATE@LISTSERV.UGA.EDU (Linux 2.6.32) 5 62720 EXCEL@LISTSERV.UTA.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 6 59546 GLOBAL-LINKS@LISTSERV.ELCA.ORG (Windows Server 2003 + LSMTP V1.1b) 7 40871 OPSWNEWS@LISTSERV.NYSED.GOV (AIX 7.1) 8 40764 SAFETYNOTICE@LISTSERV.UC.EDU (Windows Server 2012 R2 Datacenter x64 Edition) 9 34586 TCUATHLETICSDIRECTOR@LISTSERV.TCU.EDU (Windows Server 2012 R2 Standard x64 Edition) 10 33873 ASMSU@LIST.MSU.EDU (Linux 3.0.34) 11 33620 L-SMEAL-REPORT@LISTS.PSU.EDU (AIX 6.1) 12 33588 EDREV@LISTS.ASU.EDU (Linux 2.6.18) 13 30849 FOCIS_GROUP@LISTS.WAYNE.EDU (Linux 2.6.18) 14 29697 L-FACSTAFF-NEWSWIRE-UP@LISTS.PSU.EDU (AIX 6.1) 15 28263 L-THON-NEWS@LISTS.PSU.EDU (AIX 6.1) 16 27734 RECREATION@LISTSERV.MIAMIOH.EDU (Windows Server 2012 R2 Standard x64 Edition) 17 27650 HALLCOLIBRARY-L@LISTSERV.UGA.EDU (Linux 2.6.32) 18 27423 VOLUPDATE@LISTSERV.UTK.EDU (Solaris 2.10) 19 26342 PARENTS@LISTSERV.TAMU.EDU (Linux 3.0.101) 20 25441 CSTORE@LIST.MSU.EDU (Linux 3.0.34)