![[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 753379 JISCMAIL.AC.UK (Windows Server 2008 R2 Enterprise x64 Edition) 2 373940 LSERV.CARDSYS.AT (Linux 4.4.59-1-pve) 3 271659 LISTS.PSU.EDU (AIX 6.1) 4 265283 DIGITAL.ANNEXBUSINESSMEDIA.COM (Linux 3.13.0-32-generic) 5 227659 LISTSERV.LIV.AC.UK (Linux 2.6.32) 6 219571 LISTSERV.ACM.ORG (Windows Server 2008 R2 Datacenter x64 Edition) 7 200709 LISTSERV.BUFFALO.EDU (Solaris 2.11) 8 192236 LISTSERV.REDIRIS.ES (Linux 2.6.32-504.3.3.el6.x86_64) 9 187841 LSV.UKY.EDU (Windows Server 2012 R2 Datacenter x64 Edition) 10 184182 LISTSERV.TAMU.EDU (Linux 3.0.101) 11 169342 H-NET.MSU.EDU (Linux 2.6.32) 12 165722 DISCUSSIONS.EQ.EDU.AU (Linux 2.6.18-404.el5) 13 160802 LISTSERV.ICORS.ORG (Windows Server 2008 R2 Datacenter x64 Edition) 14 150731 LISTSERV.UGA.EDU (Linux 2.6.32) 15 148178 LISTSERV.SYR.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 16 147149 LIST.ETSI.ORG (Windows Server 2008 R2 Standard x64 Edition) 17 128112 LISTSERV.UIC.EDU (Linux 2.6.32-504.8.1.el6.x86_64) 18 124689 LISTS.UFL.EDU (Linux 2.6.18) 19 121999 LISTSERV.AAP.ORG (Windows Server 2003 R2 + LSMTP V1.1b) 20 119412 LISTSERV.UA.EDU (Linux 3.0.101)
Pos Subscribers Site --- ----------- ---- 1 4991875 LISTS.PSU.EDU (AIX 6.1) 2 3534477 LISTES.ULAVAL.CA (Linux 2.6.18) 3 1805899 LS.KULEUVEN.BE (Linux 2.6.32) 4 1449897 LISTS.WAYNE.EDU (Linux 2.6.18) 5 1336944 LISTSERV.TAU.AC.IL (Linux 2.6.9) 6 1326866 LSV.UKY.EDU (Windows Server 2012 R2 Datacenter x64 Edition) 7 1290511 LISTSERV.TAMU.EDU (Linux 3.0.101) 8 1266737 LISTSERV.UGA.EDU (Linux 2.6.32) 9 1059036 LISTS.UFL.EDU (Linux 2.6.18) 10 1028744 LISTSERV.BUFFALO.EDU (Solaris 2.11) 11 990283 LIST.MSU.EDU (Linux 3.0.34) 12 944785 LISTS.UMN.EDU (Linux 2.6.32) 13 940975 LISTSERV.UTORONTO.CA (Linux 2.6.18) 14 940240 LISTSERV.ND.EDU (Linux 2.6.18) 15 900165 LISTSERV.UA.EDU (Linux 3.0.101) 16 818258 CUVMC.AIS.COLUMBIA.EDU (VM/SP 4.0) 17 770702 LISTSERV.SYR.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 18 761415 LISTSERV.UH.EDU (Linux 2.6.18) 19 741112 LISTSERV.NODAK.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 20 706775 LISTSERV.MIAMIOH.EDU (Windows Server 2012 R2 Standard x64 Edition)
Pos Lists Site --- ----- ---- 1 26777 LISTES.ULAVAL.CA (Linux 2.6.18) 2 19474 LISTS.PSU.EDU (AIX 6.1) 3 14020 LSV.UKY.EDU (Windows Server 2012 R2 Datacenter x64 Edition) 4 13292 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 6845 MARIST (VM/SP 2.0) 8 6654 LISTSERV.TAMU.EDU (Linux 3.0.101) 9 6491 LISTSERV.MIAMIOH.EDU (Windows Server 2012 R2 Standard x64 Edition) 10 6381 LISTSERV.TECHNION.AC.IL (Linux 2.6.32) 11 5940 LISTSERV.LIV.AC.UK (Linux 2.6.32) 12 5720 LISTSERV.MILLERSVILLE.EDU (Linux 2.6.32) 13 5472 LISTS.UMN.EDU (Linux 2.6.32) 14 4889 LISTSERV.UGA.EDU (Linux 2.6.32) 15 4374 LISTSERV.NODAK.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 16 4074 LISTSERV.UTORONTO.CA (Linux 2.6.18) 17 3992 LISTSERV.ND.EDU (Linux 2.6.18) 18 3869 LS.KULEUVEN.BE (Linux 2.6.32) 19 3726 LISTS.QUEENSU.CA (Solaris 2.10) 20 3590 LISTSERV.SYR.EDU (Windows Server 2008 R2 Enterprise x64 Edition)
Pos Recipients Site --- ---------- ---- 1 726721 JISCMAIL.AC.UK (Windows Server 2008 R2 Enterprise x64 Edition) 2 266674 LISTS.PSU.EDU (AIX 6.1) 3 217653 LISTSERV.LIV.AC.UK (Linux 2.6.32) 4 195597 LISTSERV.BUFFALO.EDU (Solaris 2.11) 5 188943 LISTSERV.REDIRIS.ES (Linux 2.6.32-504.3.3.el6.x86_64) 6 185323 LSV.UKY.EDU (Windows Server 2012 R2 Datacenter x64 Edition) 7 183013 LISTSERV.TAMU.EDU (Linux 3.0.101) 8 167496 H-NET.MSU.EDU (Linux 2.6.32) 9 165547 DISCUSSIONS.EQ.EDU.AU (Linux 2.6.18-404.el5) 10 156899 LISTSERV.ICORS.ORG (Windows Server 2008 R2 Datacenter x64 Edition) 11 146580 LIST.ETSI.ORG (Windows Server 2008 R2 Standard x64 Edition) 12 146335 LISTSERV.UGA.EDU (Linux 2.6.32) 13 128757 LISTSERV.SYR.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 14 127779 LISTSERV.UIC.EDU (Linux 2.6.32-504.8.1.el6.x86_64) 15 122922 LISTS.UFL.EDU (Linux 2.6.18) 16 121248 LISTSERV.AAP.ORG (Windows Server 2003 R2 + LSMTP V1.1b) 17 117764 LISTS.UCDENVER.EDU (Windows Server 2012 R2 Standard x64 Edition) 18 115040 LIST.UVM.EDU (Linux 2.6.32) 19 114098 LISTSERV.UA.EDU (Linux 3.0.101) 20 107794 LISTSERV.UCONN.EDU (Windows Server 2012 R2 Standard x64 Edition)
Pos Subscribers Site --- ----------- ---- 1 300681 COMPUTING@LIST.MSU.EDU (Linux 3.0.34) 2 62523 EXCEL@LISTSERV.UTA.EDU (Windows Server 2008 R2 Enterprise x64 Edition) 3 55994 CAREERCENTERUPDATE@LISTSERV.UGA.EDU (Linux 2.6.32) 4 54050 AMIS-CNRS-INTERNATIONAL-L@IN2P3.FR (AIX 5.3) 5 41702 OPSWNEWS@LISTSERV.NYSED.GOV (AIX 7.1) 6 34921 ASMSU@LIST.MSU.EDU (Linux 3.0.34) 7 34587 TCUATHLETICSDIRECTOR@LISTSERV.TCU.EDU (Windows Server 2012 R2 Standard x64 Edition) 8 34081 CMU-BASKETBALL@LS2.CMICH.EDU (Linux 2.6.18) 9 33618 L-SMEAL-REPORT@LISTS.PSU.EDU (AIX 6.1) 10 31307 SAFETYNOTICE@LISTSERV.UC.EDU (Windows Server 2012 R2 Datacenter x64 Edition) 11 30848 FOCIS_GROUP@LISTS.WAYNE.EDU (Linux 2.6.18) 12 28924 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 28360 L-THON-NEWS@LISTS.PSU.EDU (AIX 6.1) 16 27713 RECREATION@LISTSERV.MIAMIOH.EDU (Windows Server 2012 R2 Standard x64 Edition) 17 27418 VOLUPDATE@LISTSERV.UTK.EDU (Solaris 2.10) 18 26994 L-FACSTAFF-NEWSWIRE-UP@LISTS.PSU.EDU (AIX 6.1) 19 26420 PARENTS@LISTSERV.TAMU.EDU (Linux 3.0.101) 20 26103 CSTORE@LIST.MSU.EDU (Linux 3.0.34)