![[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 917157 JISCMAIL.AC.UK (Windows Server 2008 R2 Enterprise x64 Edition) 2 478071 LISTS.PSU.EDU (AIX 6.1) 3 308506 LISTSERV.BUFFALO.EDU (Solaris 2.11) 4 295744 LISTSERV.MED.CORNELL.EDU (SunOS 5.10) 5 287568 LISTSERV.ICORS.ORG (Windows Server 2008 R2 Datacenter x64 Edition) 6 280553 LISTSERV.UGA.EDU (Linux 2.6.32) 7 273097 LSERV.CARDSYS.AT (Linux 2.6.32-44-pve) 8 272813 LISTSERV.UMD.EDU (SunOS 5.10) 9 269936 LISTSERV.TAMU.EDU (Linux 3.0.101) 10 267242 LSV.UKY.EDU (Windows Server 2003) 11 243062 LISTS.UFL.EDU (Linux 2.6.18) 12 242409 LISTSERV.SYR.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 13 237605 H-NET.MSU.EDU (Linux 2.6.32) 14 221963 LISTSERV.LIV.AC.UK (Linux 2.6.32) 15 220657 NEWSMAIL.WYANOKEGROUP.COM (Windows Server 2008 R2 Standard x64 Edition) 16 219710 LISTSERV.ACM.ORG (Windows Server 2008 R2 Datacenter x64 Edition) 17 205931 LISTES.ULAVAL.CA (Linux 2.6.18) 18 203909 LISTSERV.DARTMOUTH.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 19 190084 LISTSERV.REDIRIS.ES (Linux 2.6.32-504.3.3.el6.x86_64) 20 181246 LISTSERV.UIC.EDU (Linux 2.6.32-504.8.1.el6.x86_64)
Pos Subscribers Site --- ----------- ---- 1 4838882 LISTS.PSU.EDU (AIX 6.1) 2 3565843 LISTES.ULAVAL.CA (Linux 2.6.18) 3 1652554 LSV.UKY.EDU (Windows Server 2003) 4 1608827 LISTSERV.UGA.EDU (Linux 2.6.32) 5 1570803 LS.KULEUVEN.BE (Linux 2.6.32) 6 1473106 LISTS.WAYNE.EDU (Linux 2.6.18) 7 1281597 LISTSERV.TAU.AC.IL (Linux 2.6.9) 8 1188293 LISTSERV.TAMU.EDU (Linux 3.0.101) 9 1059036 LISTS.UFL.EDU (Linux 2.6.18) 10 1058441 HERMES.GWU.EDU (Linux 2.6.32) 11 1024134 LIST.MSU.EDU (Linux 3.0.34) 12 1023681 LISTS.UMN.EDU (Solaris 2.10) 13 954230 LISTSERV.BUFFALO.EDU (Solaris 2.11) 14 912166 LISTSERV.ND.EDU (Linux 2.6.18) 15 879598 LISTSERV.UA.EDU (Linux 3.0.82) 16 876293 LISTSERV.UTORONTO.CA (Linux 2.6.18) 17 830812 CUVMC.AIS.COLUMBIA.EDU (VM/SP 4.0) 18 751295 LISTS.ASU.EDU (Linux 2.6.18) 19 742065 LISTSERV.MIAMIOH.EDU (Windows Server 2012 R2 Standard x64 Edition) 20 710614 LISTSERV.SYR.EDU (Windows Server 2008 R2 Enterprise x64 Edition)
Pos Lists Site --- ----- ---- 1 56770 LSV.UKY.EDU (Windows Server 2003) 2 33739 LISTS.PSU.EDU (AIX 6.1) 3 26098 LISTES.ULAVAL.CA (Linux 2.6.18) 4 12433 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 6897 LISTSERV.UGA.EDU (Linux 2.6.32) 8 6450 MARIST (VM/SP 2.0) 9 6394 LISTSERV.TECHNION.AC.IL (Linux 2.6.32) 10 6261 LISTSERV.TAMU.EDU (Linux 3.0.101) 11 6165 LISTSERV.MIAMIOH.EDU (Windows Server 2012 R2 Standard x64 Edition) 12 5975 LISTS.UMN.EDU (Solaris 2.10) 13 5185 LISTSERV.LIV.AC.UK (Linux 2.6.32) 14 4301 LISTSERV.NODAK.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 15 4014 LISTSERV.ND.EDU (Linux 2.6.18) 16 3760 LISTSERV.MILLERSVILLE.EDU (Linux 2.6.32) 17 3465 LS.KULEUVEN.BE (Linux 2.6.32) 18 3370 YORKU.CA (Linux 2.6.32) 19 3357 LISTSERV.UTORONTO.CA (Linux 2.6.18) 20 3324 LISTSERV.SYR.EDU (Windows Server 2008 R2 Enterprise x64 Edition)
Pos Recipients Site --- ---------- ---- 1 892863 JISCMAIL.AC.UK (Windows Server 2008 R2 Enterprise x64 Edition) 2 472879 LISTS.PSU.EDU (AIX 6.1) 3 303774 LISTSERV.BUFFALO.EDU (Solaris 2.11) 4 295046 LISTSERV.MED.CORNELL.EDU (SunOS 5.10) 5 281315 LISTSERV.ICORS.ORG (Windows Server 2008 R2 Datacenter x64 Edition) 6 275101 LISTSERV.UGA.EDU (Linux 2.6.32) 7 268382 LISTSERV.TAMU.EDU (Linux 3.0.101) 8 263881 LSV.UKY.EDU (Windows Server 2003) 9 259565 LISTSERV.UMD.EDU (SunOS 5.10) 10 239366 LISTS.UFL.EDU (Linux 2.6.18) 11 235642 H-NET.MSU.EDU (Linux 2.6.32) 12 214323 LISTSERV.SYR.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 13 213392 LISTSERV.LIV.AC.UK (Linux 2.6.32) 14 205693 LISTES.ULAVAL.CA (Linux 2.6.18) 15 198592 LISTSERV.DARTMOUTH.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 16 187160 LISTSERV.REDIRIS.ES (Linux 2.6.32-504.3.3.el6.x86_64) 17 180829 LISTSERV.UIC.EDU (Linux 2.6.32-504.8.1.el6.x86_64) 18 170335 PO.MISSOURI.EDU (Windows Server 2012 R2 Standard x64 Edition) 19 168336 LISTS.HAWAII.EDU (Linux 2.6.32-573.3.1.el6.x86_64) 20 166874 LISTS.UMN.EDU (Solaris 2.10)
Pos Subscribers Site --- ----------- ---- 1 300753 COMPUTING@LIST.MSU.EDU (Linux 3.0.34) 2 299770 NYSTEACHING@LISTSERV.NYSED.GOV (AIX 7.1) 3 109575 COMNET@HERMES.GWU.EDU (Linux 2.6.32) 4 78834 CAREERCENTERUPDATE@LISTSERV.UGA.EDU (Linux 2.6.32) 5 62685 EXCEL@LISTSERV.UTA.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 6 41137 SAFETYNOTICE@LISTSERV.UC.EDU (Windows Server 2012 R2 Datacenter x64 Edition) 7 41081 OPSWNEWS@LISTSERV.NYSED.GOV (AIX 7.1) 8 34961 ASMSU@LIST.MSU.EDU (Linux 3.0.34) 9 34588 TCUATHLETICSDIRECTOR@LISTSERV.TCU.EDU (Windows Server 2012 R2 Standard x64 Edition) 10 33621 L-SMEAL-REPORT@LISTS.PSU.EDU (AIX 6.1) 11 33588 EDREV@LISTS.ASU.EDU (Linux 2.6.18) 12 30849 FOCIS_GROUP@LISTS.WAYNE.EDU (Linux 2.6.18) 13 29906 L-FACSTAFF-NEWSWIRE-UP@LISTS.PSU.EDU (AIX 6.1) 14 28261 L-THON-NEWS@LISTS.PSU.EDU (AIX 6.1) 15 27916 HALLCOLIBRARY-L@LISTSERV.UGA.EDU (Linux 2.6.32) 16 27726 RECREATION@LISTSERV.MIAMIOH.EDU (Windows Server 2012 R2 Standard x64 Edition) 17 27428 VOLUPDATE@LISTSERV.UTK.EDU (Solaris 2.10) 18 26414 PARENTS@LISTSERV.TAMU.EDU (Linux 3.0.101) 19 25426 CSTORE@LIST.MSU.EDU (Linux 3.0.34) 20 25081 CCS-CEVAL@LISTSERV.UOGUELPH.CA (Linux 2.6.18)