![[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 900480 JISCMAIL.AC.UK (Windows Server 2008 R2 Enterprise x64 Edition) 2 516627 LISTS.PSU.EDU (AIX 6.1) 3 450849 LISTSERV.TAMU.EDU (Linux 3.0.101) 4 391665 LISTSERV.BUFFALO.EDU (Solaris 2.11) 5 319764 LISTSERV.UGA.EDU (Linux 2.6.32) 6 303094 NEWSMAIL.WYANOKEGROUP.COM (Windows Server 2008 R2 Standard x64 Edition) 7 302259 LSV.UKY.EDU (Windows Server 2003) 8 292813 LISTSERV.SYR.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 9 272442 LISTSERV.ICORS.ORG (Windows Server 2008 R2 Datacenter x64 Edition) 10 271213 LISTSERV.UMD.EDU (SunOS 5.10) 11 258353 LISTSERV.MED.CORNELL.EDU (SunOS 5.10) 12 248194 LISTES.ULAVAL.CA (Linux 2.6.18) 13 241580 LISTSERV.DARTMOUTH.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 14 239734 LSERV.CARDSYS.AT (Linux 2.6.32-44-pve) 15 236472 LISTS.UFL.EDU (Linux 2.6.18) 16 230789 LISTSERV.LIV.AC.UK (Linux 2.6.32) 17 218423 LISTSERV.ACM.ORG (Windows Server 2008 R2 Datacenter x64 Edition) 18 215942 LISTS.HAWAII.EDU (Linux 2.6.32-573.18.1.el6.x86_64) 19 211949 LISTS.UMN.EDU (Solaris 2.10) 20 206617 LISTSERV.UIC.EDU (Linux 2.6.32-504.8.1.el6.x86_64)
Pos Subscribers Site --- ----------- ---- 1 4831163 LISTS.PSU.EDU (AIX 6.1) 2 4053134 LISTES.ULAVAL.CA (Linux 2.6.18) 3 1744876 LISTSERV.UGA.EDU (Linux 2.6.32) 4 1578250 LS.KULEUVEN.BE (Linux 2.6.32) 5 1434778 LISTS.WAYNE.EDU (Linux 2.6.18) 6 1356866 LISTSERV.TAU.AC.IL (Linux 2.6.9) 7 1230780 LSV.UKY.EDU (Windows Server 2003) 8 1171508 LISTSERV.TAMU.EDU (Linux 3.0.101) 9 1059036 LISTS.UFL.EDU (Linux 2.6.18) 10 1057462 LIST.MSU.EDU (Linux 3.0.34) 11 992299 LISTS.UMN.EDU (Solaris 2.10) 12 963344 LISTSERV.BUFFALO.EDU (Solaris 2.11) 13 904901 LISTSERV.ND.EDU (Linux 2.6.18) 14 902240 LISTSERV.UTORONTO.CA (Linux 2.6.18) 15 898073 LISTSERV.UA.EDU (Linux 3.0.82) 16 790241 CUVMC.AIS.COLUMBIA.EDU (VM/SP 4.0) 17 771693 LISTSERV.MIAMIOH.EDU (Windows Server 2012 R2 Standard x64 Edition) 18 751295 LISTS.ASU.EDU (Linux 2.6.18) 19 720509 LISTSERV.SYR.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 20 659712 LISTSERV.ECU.EDU (Windows Server 2008 R2 Enterprise x64 Edition)
Pos Lists Site --- ----- ---- 1 33917 LISTS.PSU.EDU (AIX 6.1) 2 29507 LISTES.ULAVAL.CA (Linux 2.6.18) 3 13951 LSV.UKY.EDU (Windows Server 2003) 4 12977 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 7053 LISTSERV.UGA.EDU (Linux 2.6.32) 8 6845 MARIST (VM/SP 2.0) 9 6741 LISTSERV.TECHNION.AC.IL (Linux 2.6.32) 10 6382 LISTSERV.TAMU.EDU (Linux 3.0.101) 11 6192 LISTSERV.MIAMIOH.EDU (Windows Server 2012 R2 Standard x64 Edition) 12 5682 LISTS.UMN.EDU (Solaris 2.10) 13 5453 LISTSERV.LIV.AC.UK (Linux 2.6.32) 14 4309 LISTSERV.NODAK.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 15 3990 LISTSERV.ND.EDU (Linux 2.6.18) 16 3873 LISTSERV.MILLERSVILLE.EDU (Linux 2.6.32) 17 3445 LISTSERV.UTORONTO.CA (Linux 2.6.18) 18 3416 LS.KULEUVEN.BE (Linux 2.6.32) 19 3398 YORKU.CA (Linux 2.6.32) 20 3372 LISTSERV.SYR.EDU (Windows Server 2008 R2 Enterprise x64 Edition)
Pos Recipients Site --- ---------- ---- 1 875782 JISCMAIL.AC.UK (Windows Server 2008 R2 Enterprise x64 Edition) 2 511354 LISTS.PSU.EDU (AIX 6.1) 3 448999 LISTSERV.TAMU.EDU (Linux 3.0.101) 4 387080 LISTSERV.BUFFALO.EDU (Solaris 2.11) 5 311979 LISTSERV.UGA.EDU (Linux 2.6.32) 6 298740 LSV.UKY.EDU (Windows Server 2003) 7 266505 LISTSERV.ICORS.ORG (Windows Server 2008 R2 Datacenter x64 Edition) 8 257654 LISTSERV.MED.CORNELL.EDU (SunOS 5.10) 9 250112 LISTSERV.UMD.EDU (SunOS 5.10) 10 249157 LISTSERV.SYR.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 11 247892 LISTES.ULAVAL.CA (Linux 2.6.18) 12 235533 LISTSERV.DARTMOUTH.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 13 232522 LISTS.UFL.EDU (Linux 2.6.18) 14 222269 LISTSERV.LIV.AC.UK (Linux 2.6.32) 15 214413 LISTS.HAWAII.EDU (Linux 2.6.32-573.18.1.el6.x86_64) 16 210142 LISTS.UMN.EDU (Solaris 2.10) 17 206149 LISTSERV.UIC.EDU (Linux 2.6.32-504.8.1.el6.x86_64) 18 201863 LISTSERV.NODAK.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 19 200928 LISTSERV.UCONN.EDU (Windows Server 2012 R2 Standard x64 Edition) 20 196913 LISTSERV.REDIRIS.ES (Linux 2.6.32-504.3.3.el6.x86_64)
Pos Subscribers Site --- ----------- ---- 1 300743 COMPUTING@LIST.MSU.EDU (Linux 3.0.34) 2 300014 NYSTEACHING@LISTSERV.NYSED.GOV (AIX 7.1) 3 77138 CAREERCENTERUPDATE@LISTSERV.UGA.EDU (Linux 2.6.32) 4 62667 EXCEL@LISTSERV.UTA.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 5 54124 AMIS-CNRS-INTERNATIONAL-L@IN2P3.FR (AIX 5.3) 6 42199 SAFETYNOTICE@LISTSERV.UC.EDU (Windows Server 2012 R2 Datacenter x64 Edition) 7 41220 OPSWNEWS@LISTSERV.NYSED.GOV (AIX 7.1) 8 34951 ASMSU@LIST.MSU.EDU (Linux 3.0.34) 9 34588 TCUATHLETICSDIRECTOR@LISTSERV.TCU.EDU (Windows Server 2012 R2 Standard x64 Edition) 10 33622 L-SMEAL-REPORT@LISTS.PSU.EDU (AIX 6.1) 11 33588 EDREV@LISTS.ASU.EDU (Linux 2.6.18) 12 30848 FOCIS_GROUP@LISTS.WAYNE.EDU (Linux 2.6.18) 13 30727 L-FACSTAFF-NEWSWIRE-UP@LISTS.PSU.EDU (AIX 6.1) 14 28918 BEDRIJVENLIJST@LS.KULEUVEN.BE (Linux 2.6.32) 15 28918 BEDRIJVENLIJST2@LS.KULEUVEN.BE (Linux 2.6.32) 16 28381 HALLCOLIBRARY-L@LISTSERV.UGA.EDU (Linux 2.6.32) 17 28280 L-THON-NEWS@LISTS.PSU.EDU (AIX 6.1) 18 27723 RECREATION@LISTSERV.MIAMIOH.EDU (Windows Server 2012 R2 Standard x64 Edition) 19 27425 VOLUPDATE@LISTSERV.UTK.EDU (Solaris 2.10) 20 26415 PARENTS@LISTSERV.TAMU.EDU (Linux 3.0.101)